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class="vector-toc-list"> <li id="toc-Materials" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Materials"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1</span> <span>Materials</span> </div> </a> <ul id="toc-Materials-sublist" class="vector-toc-list"> <li id="toc-Steels" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Steels"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1.1</span> <span>Steels</span> </div> </a> <ul id="toc-Steels-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Others" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Others"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1.2</span> <span>Others</span> </div> </a> <ul id="toc-Others-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Coatings" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Coatings"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2</span> <span>Coatings</span> </div> </a> <ul id="toc-Coatings-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Universal_bits" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Universal_bits"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Universal bits</span> </div> </a> <button aria-controls="toc-Universal_bits-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Universal bits subsection</span> </button> <ul id="toc-Universal_bits-sublist" class="vector-toc-list"> <li id="toc-Twist_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Twist_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Twist drill bit</span> </div> </a> <ul id="toc-Twist_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Step_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Step_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Step drill bit</span> </div> </a> <ul id="toc-Step_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Unibit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Unibit"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Unibit</span> </div> </a> <ul id="toc-Unibit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Hole_saw" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Hole_saw"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.4</span> <span>Hole saw</span> </div> </a> <ul id="toc-Hole_saw-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-For_metal" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#For_metal"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>For metal</span> </div> </a> <button aria-controls="toc-For_metal-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle For metal subsection</span> </button> <ul id="toc-For_metal-sublist" class="vector-toc-list"> <li id="toc-Center_and_spotting_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Center_and_spotting_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>Center and spotting drill bit</span> </div> </a> <ul id="toc-Center_and_spotting_drill_bit-sublist" class="vector-toc-list"> <li id="toc-Use_in_making_holes_for_lathe_centers" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Use_in_making_holes_for_lathe_centers"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1.1</span> <span>Use in making holes for lathe centers</span> </div> </a> <ul id="toc-Use_in_making_holes_for_lathe_centers-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Use_in_spotting_hole_centers" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Use_in_spotting_hole_centers"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1.2</span> <span>Use in spotting hole centers</span> </div> </a> <ul id="toc-Use_in_spotting_hole_centers-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Core_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Core_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Core drill bit</span> </div> </a> <ul id="toc-Core_drill_bit-sublist" class="vector-toc-list"> <li id="toc-Enlarging_holes" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Enlarging_holes"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2.1</span> <span>Enlarging holes</span> </div> </a> <ul id="toc-Enlarging_holes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Extracting_core" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Extracting_core"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2.2</span> <span>Extracting core</span> </div> </a> <ul id="toc-Extracting_core-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Countersink_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Countersink_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3</span> <span>Countersink bit</span> </div> </a> <ul id="toc-Countersink_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Ejector_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Ejector_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.4</span> <span>Ejector drill bit</span> </div> </a> <ul id="toc-Ejector_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Gun_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Gun_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.5</span> <span>Gun drill bit</span> </div> </a> <ul id="toc-Gun_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Indexable_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Indexable_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.6</span> <span>Indexable drill bit</span> </div> </a> <ul id="toc-Indexable_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Left-hand_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Left-hand_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.7</span> <span>Left-hand bit</span> </div> </a> <ul id="toc-Left-hand_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Metal_spade_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Metal_spade_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.8</span> <span>Metal spade bit</span> </div> </a> <ul id="toc-Metal_spade_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Straight_fluted_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Straight_fluted_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.9</span> <span>Straight fluted bit</span> </div> </a> <ul id="toc-Straight_fluted_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Trepan" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Trepan"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.10</span> <span>Trepan</span> </div> </a> <ul id="toc-Trepan-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-For_wood" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#For_wood"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>For wood</span> </div> </a> <button aria-controls="toc-For_wood-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle For wood subsection</span> </button> <ul id="toc-For_wood-sublist" class="vector-toc-list"> <li id="toc-Brad_point_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Brad_point_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Brad point bit</span> </div> </a> <ul id="toc-Brad_point_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Wood_spade_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Wood_spade_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Wood spade bit</span> </div> </a> <ul id="toc-Wood_spade_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Spoon_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Spoon_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Spoon bit</span> </div> </a> <ul id="toc-Spoon_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Forstner_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Forstner_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4</span> <span>Forstner bit</span> </div> </a> <ul id="toc-Forstner_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Center_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Center_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5</span> <span>Center bit</span> </div> </a> <ul id="toc-Center_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Auger_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Auger_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.6</span> <span>Auger bit</span> </div> </a> <ul id="toc-Auger_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Gimlet_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Gimlet_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.7</span> <span>Gimlet bit</span> </div> </a> <ul id="toc-Gimlet_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Hinge_sinker_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Hinge_sinker_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.8</span> <span>Hinge sinker bit</span> </div> </a> <ul id="toc-Hinge_sinker_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Adjustable_wood_bits" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Adjustable_wood_bits"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.9</span> <span>Adjustable wood bits</span> </div> </a> <ul id="toc-Adjustable_wood_bits-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Other_materials" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Other_materials"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Other materials</span> </div> </a> <button aria-controls="toc-Other_materials-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Other materials subsection</span> </button> <ul id="toc-Other_materials-sublist" class="vector-toc-list"> <li id="toc-Diamond_core_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Diamond_core_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.1</span> <span>Diamond core bit</span> </div> </a> <ul id="toc-Diamond_core_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Masonry_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Masonry_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.2</span> <span>Masonry drill bit</span> </div> </a> <ul id="toc-Masonry_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Glass_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Glass_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.3</span> <span>Glass drill bit</span> </div> </a> <ul id="toc-Glass_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Ceramic_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Ceramic_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.4</span> <span>Ceramic drill bit</span> </div> </a> <ul id="toc-Ceramic_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-PCB_through-hole_drill_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#PCB_through-hole_drill_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.5</span> <span>PCB through-hole drill bit</span> </div> </a> <ul id="toc-PCB_through-hole_drill_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Installer_bit" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Installer_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.6</span> <span>Installer bit</span> </div> </a> <ul id="toc-Installer_bit-sublist" class="vector-toc-list"> <li id="toc-Fishing_bit" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Fishing_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.6.1</span> <span>Fishing bit</span> </div> </a> <ul id="toc-Fishing_bit-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Flexible_shaft_bit" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Flexible_shaft_bit"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.6.2</span> <span>Flexible shaft bit</span> </div> </a> <ul id="toc-Flexible_shaft_bit-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> <li id="toc-Drill_bit_shank" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Drill_bit_shank"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Drill bit shank</span> </div> </a> <ul id="toc-Drill_bit_shank-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>References</span> </div> </a> <button aria-controls="toc-References-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle References subsection</span> </button> <ul id="toc-References-sublist" class="vector-toc-list"> <li id="toc-Citations" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Citations"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.1</span> <span>Citations</span> </div> </a> <ul id="toc-Citations-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Cited_references" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Cited_references"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.2</span> <span>Cited references</span> </div> </a> <ul id="toc-Cited_references-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Drill bit</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 49 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-49" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">49 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Boorpunt" title="Boorpunt – Afrikaans" lang="af" hreflang="af" data-title="Boorpunt" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%84%D9%82%D9%85%D8%A9_%D8%AB%D9%82%D8%A8" title="لقمة ثقب – Arabic" lang="ar" hreflang="ar" data-title="لقمة ثقب" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Bur%C4%9Fulama" title="Burğulama – Azerbaijani" lang="az" hreflang="az" data-title="Burğulama" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-azb mw-list-item"><a href="https://azb.wikipedia.org/wiki/%D8%A8%D9%88%D8%B1%D8%BA%D9%88" title="بورغو – South Azerbaijani" lang="azb" hreflang="azb" data-title="بورغو" data-language-autonym="تۆرکجه" data-language-local-name="South Azerbaijani" class="interlanguage-link-target"><span>تۆرکجه</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%A1%D0%B2%D0%B5%D1%80%D0%B4%D0%B7%D0%B5%D0%BB" title="Свердзел – Belarusian" lang="be" hreflang="be" data-title="Свердзел" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%A1%D0%B2%D1%80%D0%B5%D0%B4%D0%BB%D0%BE" title="Свредло – Bulgarian" lang="bg" hreflang="bg" data-title="Свредло" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bo mw-list-item"><a href="https://bo.wikipedia.org/wiki/%E0%BD%82%E0%BD%A6%E0%BD%BC%E0%BD%A2%E0%BC%8B%E0%BD%A0%E0%BD%96%E0%BD%B2%E0%BD%82%E0%BD%A6%E0%BC%8D" title="གསོར་འབིགས། – Tibetan" lang="bo" hreflang="bo" data-title="གསོར་འབིགས།" data-language-autonym="བོད་ཡིག" data-language-local-name="Tibetan" class="interlanguage-link-target"><span>བོད་ཡིག</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Broca" title="Broca – Catalan" lang="ca" hreflang="ca" data-title="Broca" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%9F%C4%83%D1%80%D0%B0%D0%BB%D0%B0%D0%B2%C4%83%D1%88" title="Пăралавăш – Chuvash" lang="cv" hreflang="cv" data-title="Пăралавăш" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Vrt%C3%A1k" title="Vrták – Czech" lang="cs" hreflang="cs" data-title="Vrták" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Bor_(redskab)" title="Bor (redskab) – Danish" lang="da" hreflang="da" data-title="Bor (redskab)" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Bohrer" title="Bohrer – German" lang="de" hreflang="de" data-title="Bohrer" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Puur" title="Puur – Estonian" lang="et" hreflang="et" data-title="Puur" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Broca" title="Broca – Spanish" lang="es" hreflang="es" data-title="Broca" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Borpinto" title="Borpinto – Esperanto" lang="eo" hreflang="eo" data-title="Borpinto" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Barauts" title="Barauts – Basque" lang="eu" hreflang="eu" data-title="Barauts" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%85%D8%AA%D9%87" title="مته – Persian" lang="fa" hreflang="fa" data-title="مته" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Foret" title="Foret – French" lang="fr" hreflang="fr" data-title="Foret" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%93%9C%EB%A6%B4_%EB%B9%84%ED%8A%B8" title="드릴 비트 – Korean" lang="ko" hreflang="ko" data-title="드릴 비트" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%A1%E0%A5%8D%E0%A4%B0%E0%A4%BF%E0%A4%B2_%E0%A4%AC%E0%A4%BF%E0%A4%9F" title="ड्रिल बिट – Hindi" lang="hi" hreflang="hi" data-title="ड्रिल बिट" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Svrdlo" title="Svrdlo – Croatian" lang="hr" hreflang="hr" data-title="Svrdlo" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Bor_(verkf%C3%A6ri)" title="Bor (verkfæri) – Icelandic" lang="is" hreflang="is" data-title="Bor (verkfæri)" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Punta_da_trapano" title="Punta da trapano – Italian" lang="it" hreflang="it" data-title="Punta da trapano" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%9E%D7%A7%D7%93%D7%97" title="מקדח – Hebrew" lang="he" hreflang="he" data-title="מקדח" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-pam mw-list-item"><a href="https://pam.wikipedia.org/wiki/Taram_barena" title="Taram barena – Pampanga" lang="pam" hreflang="pam" data-title="Taram barena" data-language-autonym="Kapampangan" data-language-local-name="Pampanga" class="interlanguage-link-target"><span>Kapampangan</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%91%D2%B1%D1%80%D2%93%D1%8B" title="Бұрғы – Kazakh" lang="kk" hreflang="kk" data-title="Бұрғы" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-kv mw-list-item"><a href="https://kv.wikipedia.org/wiki/%D0%9F%D0%B8%D1%81%D1%8C%D0%BA%D3%A7%D0%B4%D1%87%D0%B0%D0%BD" title="Писькӧдчан – Komi" lang="kv" hreflang="kv" data-title="Писькӧдчан" data-language-autonym="Коми" data-language-local-name="Komi" class="interlanguage-link-target"><span>Коми</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Urbis" title="Urbis – Latvian" lang="lv" hreflang="lv" data-title="Urbis" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Gr%C4%85%C5%BEtas" title="Grąžtas – Lithuanian" lang="lt" hreflang="lt" data-title="Grąžtas" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-li mw-list-item"><a href="https://li.wikipedia.org/wiki/Baor" title="Baor – Limburgish" lang="li" hreflang="li" data-title="Baor" data-language-autonym="Limburgs" data-language-local-name="Limburgish" class="interlanguage-link-target"><span>Limburgs</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/F%C3%BAr%C3%A1s_(f%C3%A9mmegmunk%C3%A1l%C3%A1s)" title="Fúrás (fémmegmunkálás) – Hungarian" lang="hu" hreflang="hu" data-title="Fúrás (fémmegmunkálás)" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Boor_(gereedschap)" title="Boor (gereedschap) – Dutch" lang="nl" hreflang="nl" data-title="Boor (gereedschap)" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%83%89%E3%83%AA%E3%83%AB_(%E5%B7%A5%E5%85%B7)" title="ドリル (工具) – Japanese" lang="ja" hreflang="ja" data-title="ドリル (工具)" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Bor_(redskap)" title="Bor (redskap) – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Bor (redskap)" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Parma" title="Parma – Uzbek" lang="uz" hreflang="uz" data-title="Parma" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Wiert%C5%82o" title="Wiertło – Polish" lang="pl" hreflang="pl" data-title="Wiertło" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Broca" title="Broca – Portuguese" lang="pt" hreflang="pt" data-title="Broca" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%A1%D0%B2%D0%B5%D1%80%D0%BB%D0%BE" title="Сверло – Russian" lang="ru" hreflang="ru" data-title="Сверло" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-stq mw-list-item"><a href="https://stq.wikipedia.org/wiki/Boor" title="Boor – Saterland Frisian" lang="stq" hreflang="stq" data-title="Boor" data-language-autonym="Seeltersk" data-language-local-name="Saterland Frisian" class="interlanguage-link-target"><span>Seeltersk</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Koka_e_shpuesit" title="Koka e shpuesit – Albanian" lang="sq" hreflang="sq" data-title="Koka e shpuesit" data-language-autonym="Shqip" data-language-local-name="Albanian" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Vrt%C3%A1k" title="Vrták – Slovak" lang="sk" hreflang="sk" data-title="Vrták" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/Burgija" title="Burgija – Serbian" lang="sr" hreflang="sr" data-title="Burgija" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Svrdlo" title="Svrdlo – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Svrdlo" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a 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mw-list-item"><a href="https://tr.wikipedia.org/wiki/Burgu" title="Burgu – Turkish" lang="tr" hreflang="tr" data-title="Burgu" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A1%D0%B2%D0%B5%D1%80%D0%B4%D0%BB%D0%BE" title="Свердло – Ukrainian" lang="uk" hreflang="uk" data-title="Свердло" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E9%91%BD%E9%A0%AD" title="鑽頭 – Chinese" lang="zh" hreflang="zh" data-title="鑽頭" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit 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searchaux" style="display:none">Type of cutting tool</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">For the types used in drilling holes in the ground, see <a href="/wiki/Well_drilling" title="Well drilling">Well drilling</a>.</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">For other uses, see <a href="/wiki/Drill_bit_(disambiguation)" class="mw-disambig" title="Drill bit (disambiguation)">Drill bit (disambiguation)</a>.</div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px 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.mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-Lead_extra_info plainlinks metadata ambox ambox-style ambox-lead_extra_info" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/f/f2/Edit-clear.svg/40px-Edit-clear.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/f/f2/Edit-clear.svg/60px-Edit-clear.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/f/f2/Edit-clear.svg/80px-Edit-clear.svg.png 2x" data-file-width="48" data-file-height="48" /></span></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article's <b><a href="/wiki/Wikipedia:Manual_of_Style/Lead_section" title="Wikipedia:Manual of Style/Lead section">lead section</a> contains information that is not included elsewhere in the article</b>.<span class="hide-when-compact"> If the information is appropriate for the lead of the article, this information should also be included in the body of the article.</span> <span class="date-container"><i>(<span class="date">August 2023</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Drill_bit" title="Special:EditPage/Drill bit">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Drill+bit%22">"Drill bit"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Drill+bit%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Drill+bit%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Drill+bit%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Drill+bit%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Drill+bit%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">July 2021</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Drillbits.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c3/Drillbits.jpg/220px-Drillbits.jpg" decoding="async" width="220" height="124" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c3/Drillbits.jpg/330px-Drillbits.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c3/Drillbits.jpg/440px-Drillbits.jpg 2x" data-file-width="628" data-file-height="354" /></a><figcaption>From top: Spade, <a href="#Brad_point_bit">brad point</a>, <a href="#Masonry_drill_bit">masonry</a>, and <a href="#Twist_drill_bit">twist drills bits</a></figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Pistol-grip_drill.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Pistol-grip_drill.svg/220px-Pistol-grip_drill.svg.png" decoding="async" width="220" height="162" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Pistol-grip_drill.svg/330px-Pistol-grip_drill.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Pistol-grip_drill.svg/440px-Pistol-grip_drill.svg.png 2x" data-file-width="746" data-file-height="549" /></a><figcaption>Drill bit (upper left), mounted on a pistol-grip electric <a href="/wiki/Drill" title="Drill">drill</a></figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Drill_bits_2017_G1.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Drill_bits_2017_G1.jpg/220px-Drill_bits_2017_G1.jpg" decoding="async" width="220" height="138" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Drill_bits_2017_G1.jpg/330px-Drill_bits_2017_G1.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Drill_bits_2017_G1.jpg/440px-Drill_bits_2017_G1.jpg 2x" data-file-width="5600" data-file-height="3500" /></a><figcaption>A set of masonry drills</figcaption></figure> <p>A <b>drill bit</b> is a cutting tool used in a drill to remove material to create holes, almost always of circular cross-section. Drill bits come in many sizes and shapes and can create different kinds of holes in many different materials. In order to create holes drill bits are usually attached to a <a href="/wiki/Drill" title="Drill">drill</a>, which powers them to cut through the workpiece, typically by rotation. The drill will grasp the upper end of a bit called the <i>shank</i> in the <a href="/wiki/Chuck_(engineering)" title="Chuck (engineering)">chuck</a>. </p><p>Drills come in standardized <a href="/wiki/Drill_bit_sizes" title="Drill bit sizes">drill bit sizes</a>. A comprehensive <a href="/wiki/Drill_and_tap_size_chart" class="mw-redirect" title="Drill and tap size chart">drill bit and tap size chart</a> lists <a href="/wiki/Metric_system" title="Metric system">metric</a> and <a href="/wiki/Imperial_system" class="mw-redirect" title="Imperial system">imperial</a> sized drills alongside the required screw tap sizes. There are also certain specialized drill bits that can create holes with a non-circular cross-section.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Characteristics">Characteristics</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=1" title="Edit section: Characteristics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Drill_bit_sizes" title="Drill bit sizes">Drill bit sizes</a></div> <p>Drill geometry has several characteristics: </p> <ul><li>The <b>spiral</b> (or rate of twist) in the drill bit controls the rate of <a href="/wiki/Swarf" title="Swarf">chip</a> removal. A fast spiral (high twist rate or "compact flute") drill bit is used in high feed rate applications under low spindle speeds, where removal of a large volume of chips is required. Low spiral (low twist rate or "elongated flute") drill bits are used in cutting applications where high cutting speeds are traditionally used, and where the material has a tendency to <a href="/wiki/Galling" title="Galling">gall</a> on the bit or otherwise clog the hole, such as <a href="/wiki/Aluminum" class="mw-redirect" title="Aluminum">aluminum</a> or <a href="/wiki/Copper" title="Copper">copper</a>.</li> <li>The <b>point angle</b>, or the angle formed at the tip of the bit, is determined by the material the bit will be operating in. Harder materials require a larger point angle, and softer materials require a sharper angle. The correct point angle for the hardness of the material influences wandering, chatter, hole shape, and wear rate.</li> <li>The <b>lip angle</b> is the angle between the face of the cut material and the flank of the lip, and determines the amount of support provided to the cutting edge. A greater lip angle will cause the bit to cut more aggressively under the same amount of point pressure as a bit with a smaller lip angle. Both conditions can cause binding, wear, and eventual catastrophic failure of the tool. The proper amount of lip clearance is determined by the point angle. A very acute point angle has more web surface area presented to the work at any one time, requiring an aggressive lip angle, where a flat bit is extremely sensitive to small changes in lip angle due to the small surface area supporting the cutting edges.</li> <li>The <b>functional length</b> of a bit determines how deep a hole can be drilled, and also determines the stiffness of the bit and accuracy of the resultant hole. While longer bits can drill deeper holes, they are more flexible meaning that the holes they drill may have an inaccurate location or wander from the intended axis. Twist drill bits are available in standard lengths, referred to as Stub-length or Screw-Machine-length (short), the extremely common <a href="/wiki/Drill_bit_sizes#Jobber-length_drill" title="Drill bit sizes">Jobber-length</a> (medium), and Taper-length or Long-Series (long).</li></ul> <p>Most drill bits for consumer use have straight shanks. For heavy duty drilling in industry, bits with <a href="/wiki/Morse_taper" class="mw-redirect" title="Morse taper">tapered</a> shanks are sometimes used. Other types of shank used include hex-shaped, and various proprietary quick release systems. </p><p>The diameter-to-length ratio of the drill bit is usually between 1:1 and 1:10. Much higher ratios are possible (e.g., "aircraft-length" twist bits, pressured-oil <a href="/wiki/Gun_drill" title="Gun drill">gun drill bits</a>, etc.), but the higher the ratio, the greater the technical challenge of producing good work. </p><p>The best geometry to use depends upon the properties of the material being drilled. The following table lists geometries recommended for some commonly drilled materials. </p> <table class="wikitable" style="text-align:right;"> <caption>Tool geometry<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </caption> <tbody><tr> <th>Workpiece material </th> <th>Point angle </th> <th>Helix angle </th> <th>Lip relief angle </th></tr> <tr> <td><div style="float:left;">Aluminum</div> </td> <td>90–135 </td> <td>32–48 </td> <td>12–26 </td></tr> <tr> <td><div style="float:left;"><a href="/wiki/Brass" title="Brass">Brass</a></div> </td> <td>90–118 </td> <td>0–20 </td> <td>12–26 </td></tr> <tr> <td><div style="float:left;"><a href="/wiki/Cast_iron" title="Cast iron">Cast iron</a></div> </td> <td>90–118 </td> <td>24–32 </td> <td>7–20 </td></tr> <tr> <td><div style="float:left;"><a href="/wiki/Mild_steel" class="mw-redirect" title="Mild steel">Mild steel</a></div> </td> <td>118–135 </td> <td>24–32 </td> <td>7–24 </td></tr> <tr> <td><div style="float:left;"><a href="/wiki/Stainless_steel" title="Stainless steel">Stainless steel</a></div> </td> <td>118–135 </td> <td>24–32 </td> <td>7–24 </td></tr> <tr> <td><div style="float:left;">Plastics</div> </td> <td>60–90 </td> <td>0–20 </td> <td>12–26 </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Materials">Materials</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=2" title="Edit section: Materials"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Titanium_nitride_coating.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Titanium_nitride_coating.jpg/75px-Titanium_nitride_coating.jpg" decoding="async" width="75" height="462" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Titanium_nitride_coating.jpg/113px-Titanium_nitride_coating.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2b/Titanium_nitride_coating.jpg/150px-Titanium_nitride_coating.jpg 2x" data-file-width="165" data-file-height="1016" /></a><figcaption><a href="/wiki/Titanium_nitride" title="Titanium nitride">Titanium nitride</a> coated twist bit</figcaption></figure> <p>Many different materials are used for or on drill bits, depending on the required application. Many hard materials, such as carbides, are much more brittle than steel, and are far more subject to breaking, particularly if the drill is not held at a very constant angle to the workpiece; e.g., when hand-held. </p> <div class="mw-heading mw-heading4"><h4 id="Steels">Steels</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=3" title="Edit section: Steels"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Soft <b>low-carbon <a href="/wiki/Steel" title="Steel">steel</a></b> bits are inexpensive, but do not hold an edge well and require frequent sharpening. They are used only for drilling wood; even working with <a href="/wiki/Hardwood" title="Hardwood">hardwoods</a> rather than <a href="/wiki/Softwood" title="Softwood">softwoods</a> can noticeably shorten their lifespan.</li> <li>Bits made from <b>high-carbon steel</b> are more durable than low-carbon steel bits due to the properties conferred by <a href="/wiki/Heat_treatment" class="mw-redirect" title="Heat treatment">hardening and tempering</a> the material. If they are overheated (e.g., by frictional heating while drilling) they lose their <a href="/wiki/Tempering_(metallurgy)" title="Tempering (metallurgy)">temper</a>, resulting in a soft cutting edge. These bits can be used on wood or metal.</li> <li><b><a href="/wiki/High-speed_steel" title="High-speed steel">High-speed steel</a></b> (HSS) is a form of <a href="/wiki/Tool_steel" title="Tool steel">tool steel</a>; HSS bits are hard and much more resistant to heat than high-carbon steel. They can be used to drill metal, hardwood, and most other materials at greater cutting speeds than carbon-steel bits, and have largely replaced carbon steels.</li> <li><b><a href="/wiki/Cobalt" title="Cobalt">Cobalt</a> steel</b> <a href="/wiki/Alloy" title="Alloy">alloys</a> are variations on high-speed steel that contain more cobalt. They hold their hardness at much higher temperatures and are used to drill <a href="/wiki/Stainless_steel" title="Stainless steel">stainless steel</a> and other hard materials. The main disadvantage of cobalt steels is that they are more brittle than standard HSS.</li></ul> <div class="mw-heading mw-heading4"><h4 id="Others">Others</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=4" title="Edit section: Others"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><b><a href="/wiki/Tungsten_carbide" title="Tungsten carbide">Tungsten carbide</a></b> and other <a href="/wiki/Carbide" title="Carbide">carbides</a> are extremely hard and can drill virtually all materials, while holding an edge longer than other bits. The material is expensive and much more brittle than steels; consequently they are mainly used for drill-bit tips, small pieces of hard material fixed or <a href="/wiki/Brazing" title="Brazing">brazed</a> onto the tip of a bit made of less hard metal. However, it is becoming common in job shops to use solid carbide bits. In very small sizes it is difficult to fit carbide tips; in some industries, most notably <a href="/wiki/Printed_circuit_board" title="Printed circuit board">printed circuit board</a> manufacturing, requiring many holes with diameters less than 1 mm, solid carbide bits are used.</li> <li><b>Polycrystalline diamond</b> (PCD) is among the hardest of all tool materials and is therefore extremely resistant to wear. It consists of a layer of diamond particles, typically about 0.5 mm (0.020 in) thick, bonded as a <a href="/wiki/Sintered" class="mw-redirect" title="Sintered">sintered</a> mass to a tungsten-carbide support. Bits are fabricated using this material by either brazing small segments to the tip of the tool to form the cutting edges or by sintering PCD into a vein in the tungsten-carbide "nib". The nib can later be brazed to a carbide shaft; it can then be ground to complex geometries that would otherwise cause braze failure in the smaller "segments". PCD bits are typically used in the automotive, aerospace, and other industries to drill abrasive aluminum alloys, carbon-fiber reinforced plastics, and other abrasive materials, and in applications where machine downtime to replace or sharpen worn bits is exceptionally costly. PCD is not used on ferrous metals due to excess wear resulting from a reaction between the carbon in the PCD and the iron in the metal.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Coatings">Coatings</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=5" title="Edit section: Coatings"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:2mm_diamond_drill_bits_macro.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e3/2mm_diamond_drill_bits_macro.jpg/220px-2mm_diamond_drill_bits_macro.jpg" decoding="async" width="220" height="157" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e3/2mm_diamond_drill_bits_macro.jpg/330px-2mm_diamond_drill_bits_macro.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e3/2mm_diamond_drill_bits_macro.jpg/440px-2mm_diamond_drill_bits_macro.jpg 2x" data-file-width="1600" data-file-height="1143" /></a><figcaption>Diamond-coated 2 mm bits, used for drilling materials such as glass</figcaption></figure> <ul><li><a href="/wiki/Black_oxide" title="Black oxide">Black oxide</a> is an inexpensive black coating. A black oxide coating provides heat resistance and lubricity, as well as corrosion resistance. The coating increases the life of high-speed steel bits.</li> <li><a href="/wiki/Titanium_nitride" title="Titanium nitride">Titanium nitride</a> (TiN) is a very hard metallic material that can be used to coat a high-speed steel bit (usually a twist bit), extending the cutting life by three or more times. Even after sharpening, the leading edge of coating still provides improved cutting and lifetime.</li> <li><a href="/wiki/Titanium_aluminum_nitride" class="mw-redirect" title="Titanium aluminum nitride">Titanium aluminum nitride</a> (TiAlN) is a similar coating that can extend tool life five or more times.</li> <li>Titanium carbon nitride (TiCN) is another coating also superior to TiN.</li> <li>Diamond powder is used as an abrasive, most often for cutting tile, stone, and other very hard materials. Large amounts of heat are generated by friction, and diamond-coated bits often have to be water-cooled to prevent damage to the bit or the workpiece.</li> <li><a href="/wiki/Zirconium_nitride" title="Zirconium nitride">Zirconium nitride</a> has been used as a drill-bit coating for some tools under the <a href="/wiki/Craftsman_(tools)" title="Craftsman (tools)">Craftsman</a> brand name.</li> <li>Al-Chrome Silicon Nitride (AlCrSi/Ti)N is a multilayer coating made of alternating nanolayer, developed using <a href="/wiki/Chemical_vapor_deposition" title="Chemical vapor deposition">chemical vapor deposition</a> technique, is used in drilling <a href="/wiki/Carbon_fiber_reinforced_polymer" class="mw-redirect" title="Carbon fiber reinforced polymer">carbon fiber reinforced polymer</a> (CFRP) and CFRP-Ti stack. (AlCrSi/Ti)N is a superhard ceramic coating, which performs better than other coated and uncoated drill.<sup id="cite_ref-doi.org_3-0" class="reference"><a href="#cite_note-doi.org-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></li> <li>BAM coating is <a href="/wiki/Boron" title="Boron">Boron</a>-Aluminum-<a href="/wiki/Magnesium" title="Magnesium">Magnesium</a> BAlMgB14 is a superhard ceramic coating also used in composite drilling.<sup id="cite_ref-doi.org_3-1" class="reference"><a href="#cite_note-doi.org-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading2"><h2 id="Universal_bits">Universal bits</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=6" title="Edit section: Universal bits"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>General-purpose drill bits can be used in wood, metal, plastic, and most other materials. </p> <div class="mw-heading mw-heading3"><h3 id="Twist_drill_bit">Twist drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=7" title="Edit section: Twist drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The twist drill bit is the type produced in largest quantity today. It comprises a cutting point at the tip of a cylindrical shaft with helical flutes; the flutes act as an <a href="/wiki/Archimedean_screw" class="mw-redirect" title="Archimedean screw">Archimedean screw</a> and lift <a href="/wiki/Swarf" title="Swarf">swarf</a> out of the hole. </p><p>The modern-style twist drill bit was invented by Sir Joseph Whitworth in 1860. They were later improved by Steven A. Morse of <a href="/wiki/East_Bridgewater,_Massachusetts" title="East Bridgewater, Massachusetts">East Bridgewater, Massachusetts</a>, who experimented with the pitch of the twist.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> The original method of manufacture was to cut two grooves in opposite sides of a round bar, then to twist the bar (giving the tool its name) to produce the helical flutes. Nowadays, the drill bit is usually made by rotating the bar while moving it past a <a href="/wiki/Grinding_(abrasive_cutting)" title="Grinding (abrasive cutting)">grinding</a> wheel to cut the <a href="/wiki/Flute_(cutting_tool)" class="mw-redirect" title="Flute (cutting tool)">flutes</a> in the same manner as <a href="/wiki/Gear_cutting" title="Gear cutting">cutting helical gears</a>. </p><p>Twist drill bits range in diameter from 0.002 to 3.5 in (0.051 to 88.900 mm)<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> and can be as long as 25.5 in (650 mm).<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p><p>The geometry and sharpening of the cutting edges is crucial to the performance of the bit. Small bits that become blunt are often discarded because sharpening them correctly is difficult and they are cheap to replace. For larger bits, special grinding jigs are available. A special <a href="/wiki/Tool_grinder" class="mw-redirect" title="Tool grinder">tool grinder</a> is available for sharpening or reshaping cutting surfaces on twist drill bits in order to optimize the bit for a particular material. </p><p>Manufacturers can produce special versions of the twist drill bit, varying the geometry and the materials used, to suit particular machinery and particular materials to be cut. Twist drill bits are available in the widest choice of tooling materials. However, even for industrial users, most holes are drilled with standard <a href="/wiki/High-speed_steel" title="High-speed steel">high-speed steel</a> bits. </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:5mm_carbide_bit_displaying_shallow_point_angle.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/5mm_carbide_bit_displaying_shallow_point_angle.jpg/220px-5mm_carbide_bit_displaying_shallow_point_angle.jpg" decoding="async" width="220" height="176" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2b/5mm_carbide_bit_displaying_shallow_point_angle.jpg/330px-5mm_carbide_bit_displaying_shallow_point_angle.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2b/5mm_carbide_bit_displaying_shallow_point_angle.jpg/440px-5mm_carbide_bit_displaying_shallow_point_angle.jpg 2x" data-file-width="1600" data-file-height="1280" /></a><figcaption>A 5 mm carbide bit displaying shallow point angle.</figcaption></figure> <p>The most common twist drill bit (sold in general hardware stores) has a point angle of 118 degrees, acceptable for use in wood, metal, plastic, and most other materials, although it does not perform as well as using the optimum angle for each material. In most materials it does not tend to wander or dig in. </p><p>A more aggressive angle, such as 90 degrees, is suited for very soft plastics and other materials; it would wear rapidly in hard materials. Such a bit is generally self-starting and can cut very quickly. A shallower angle, such as 150 degrees, is suited for drilling steels and other tougher materials. This style of bit requires a starter hole, but does not bind or suffer premature wear so long as a suitable feed rate is used. </p><p>Drill bits with no point angle are used in situations where a blind, flat-bottomed hole is required. These bits are very sensitive to changes in lip angle, and even a slight change can result in an inappropriately fast cutting drill bit that will suffer premature wear. </p><p><i>Long series</i> drill bits are unusually long twist drill bits. However, they are not the best tool for routinely drilling deep holes, as they require frequent withdrawal to clear the flutes of swarf and to prevent breakage of the bit. Instead, <a href="/wiki/Gun_drill" title="Gun drill">gun drill</a> (through coolant drill) bits are preferred for deep hole drilling. </p> <ul class="gallery mw-gallery-packed"> <li class="gallerybox" style="width: 138.66666666667px"> <div class="thumb" style="width: 136.66666666667px;"><span typeof="mw:File"><a href="/wiki/File:Drill_twist_1.jpg" class="mw-file-description" title="Twist drill bit cutting edges"><img alt="Twist drill bit cutting edges" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fc/Drill_twist_1.jpg/205px-Drill_twist_1.jpg" decoding="async" width="137" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fc/Drill_twist_1.jpg/307px-Drill_twist_1.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fc/Drill_twist_1.jpg/410px-Drill_twist_1.jpg 2x" data-file-width="422" data-file-height="371" /></a></span></div> <div class="gallerytext">Twist drill bit cutting edges</div> </li> <li class="gallerybox" style="width: 275.33333333333px"> <div class="thumb" style="width: 273.33333333333px;"><span typeof="mw:File"><a href="/wiki/File:Drill_twist_morse.jpg" class="mw-file-description" title="Twist drill bit with Morse taper shank"><img alt="Twist drill bit with Morse taper shank" src="//upload.wikimedia.org/wikipedia/commons/thumb/5/51/Drill_twist_morse.jpg/410px-Drill_twist_morse.jpg" decoding="async" width="274" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/51/Drill_twist_morse.jpg/614px-Drill_twist_morse.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/51/Drill_twist_morse.jpg/819px-Drill_twist_morse.jpg 2x" data-file-width="1302" data-file-height="573" /></a></span></div> <div class="gallerytext">Twist drill bit with <a href="/wiki/Machine_taper#Morse" title="Machine taper">Morse taper</a> shank</div> </li> <li class="gallerybox" style="width: 421.33333333333px"> <div class="thumb" style="width: 419.33333333333px;"><span typeof="mw:File"><a href="/wiki/File:LongSeriesDrill-11_32.jpg" class="mw-file-description" title="11⁄32 in (8.7313 mm) drill bits - long-series morse, plain morse, jobber"><img alt="11⁄32 in (8.7313 mm) drill bits - long-series morse, plain morse, jobber" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e7/LongSeriesDrill-11_32.jpg/629px-LongSeriesDrill-11_32.jpg" decoding="async" width="420" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e7/LongSeriesDrill-11_32.jpg/944px-LongSeriesDrill-11_32.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e7/LongSeriesDrill-11_32.jpg/1258px-LongSeriesDrill-11_32.jpg 2x" data-file-width="1803" data-file-height="516" /></a></span></div> <div class="gallerytext"><style data-mw-deduplicate="TemplateStyles:r1154941027">.mw-parser-output .frac{white-space:nowrap}.mw-parser-output .frac .num,.mw-parser-output .frac .den{font-size:80%;line-height:0;vertical-align:super}.mw-parser-output .frac .den{vertical-align:sub}.mw-parser-output .sr-only{border:0;clip:rect(0,0,0,0);clip-path:polygon(0px 0px,0px 0px,0px 0px);height:1px;margin:-1px;overflow:hidden;padding:0;position:absolute;width:1px}</style><span class="frac"><span class="num">11</span>⁄<span class="den">32</span></span> in (8.7313 mm) drill bits - long-series morse, plain morse, jobber</div> </li> </ul> <div class="mw-heading mw-heading3"><h3 id="Step_drill_bit">Step drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=8" title="Edit section: Step drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A <b>step drill bit</b> is a drill bit that has the tip ground down to a different diameter. The transition between this ground diameter and the original diameter is either straight, to form a counterbore, or angled, to form a countersink. The advantage to this style is that both diameters have the same flute characteristics, which keeps the bit from clogging when drilling in softer materials, such as aluminum; in contrast, a drill bit with a slip-on collar does not have the same benefit. Most of these bits are custom-made for each application, which makes them more expensive.<sup id="cite_ref-gillespie_11-0" class="reference"><a href="#cite_note-gillespie-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Unibit">Unibit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=9" title="Edit section: Unibit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Pair_of_unibits_aka_step_bits.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c0/Pair_of_unibits_aka_step_bits.jpg/200px-Pair_of_unibits_aka_step_bits.jpg" decoding="async" width="200" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c0/Pair_of_unibits_aka_step_bits.jpg/300px-Pair_of_unibits_aka_step_bits.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c0/Pair_of_unibits_aka_step_bits.jpg/400px-Pair_of_unibits_aka_step_bits.jpg 2x" data-file-width="1600" data-file-height="1200" /></a><figcaption>A pair of unibits.</figcaption></figure> <p>A <b>unibit</b> (often called a <a href="#Step_drill_bit">step drill bit</a>) is a roughly <a href="/wiki/Cone_(geometry)" class="mw-redirect" title="Cone (geometry)">conical</a> bit with a <a href="/wiki/Stairs" title="Stairs">stairstep</a> profile.<sup id="cite_ref-gillespie_11-1" class="reference"><a href="#cite_note-gillespie-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Due to its design, a single bit can be used for drilling a wide range of hole sizes. Some bits come to a point and are thus self-starting. The larger-size bits have blunt tips and are used for hole enlarging. </p><p>Unibits are commonly used on sheet metal<sup id="cite_ref-gillespie_11-2" class="reference"><a href="#cite_note-gillespie-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> and in general construction. One drill bit can drill the entire range of holes necessary on a countertop, speeding up installation of fixtures. They are often used on softer materials, such as plywood, particle board, drywall, acrylic, and laminate. They can be used on very thin sheet metal, but metals tend to cause premature bit wear and dulling. </p><p>Unibits are ideal for use in electrical work where thin steel, aluminum or plastic boxes and chassis are encountered. The short length of the unibit and ability to vary the diameter of the finished hole is an advantage in chassis or front panel work. The finished hole can often be made quite smooth and burr-free, especially in plastic. </p><p>An additional use of unibits is deburring holes left by other bits, as the sharp increase to the next step size allows the cutting edge to scrape burrs off the entry surface of the workpiece. However, the straight flute is poor at chip ejection, and can cause a burr to be formed on the exit side of the hole, more so than a spiral twist drill bit turning at high speed. </p><p>The unibit was invented by Harry C. Oakes and <a href="/wiki/Patent" title="Patent">patented</a> in 1973.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> It was sold only by the Unibit Corporation in the 1980s until the patent expired, and was later sold by other companies. Unibit is a trademark of <a href="/wiki/Irwin_Industrial_Tools" title="Irwin Industrial Tools">Irwin Industrial Tools</a>. </p><p>Although it is claimed that the stepped drill was invented by Harry C. Oakes it was in fact conceived by George Godbold and first produced by Bradley Engineering, Wandsworth, London in the 1960s and named the Bradrad. It was marketed under this name until the patent was sold to Halls Ltd.uk by whom it is still produced. </p> <div class="mw-heading mw-heading3"><h3 id="Hole_saw">Hole saw</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=10" title="Edit section: Hole saw"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Hole_saw" title="Hole saw">Hole saw</a></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:One_and_one_quarter_inch_hole_saw_bit.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a0/One_and_one_quarter_inch_hole_saw_bit.jpg/200px-One_and_one_quarter_inch_hole_saw_bit.jpg" decoding="async" width="200" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a0/One_and_one_quarter_inch_hole_saw_bit.jpg/300px-One_and_one_quarter_inch_hole_saw_bit.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a0/One_and_one_quarter_inch_hole_saw_bit.jpg/400px-One_and_one_quarter_inch_hole_saw_bit.jpg 2x" data-file-width="1600" data-file-height="1200" /></a><figcaption>1.25 in (32 mm) hole saw bit.</figcaption></figure> <p>Hole saws take the form of a short open cylinder with saw-teeth on the open edge, used for making relatively large holes in thin material. They remove material only from the edge of the hole, cutting out an intact disc of material, unlike many drills which remove all material in the interior of the hole. They can be used to make large holes in wood, sheet metal and other materials. </p> <div class="mw-heading mw-heading2"><h2 id="For_metal">For metal</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=11" title="Edit section: For metal"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Center_and_spotting_drill_bit">Center and spotting drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=12" title="Edit section: Center and spotting drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:CenterDrills123456.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/CenterDrills123456.jpg/200px-CenterDrills123456.jpg" decoding="async" width="200" height="205" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/CenterDrills123456.jpg/300px-CenterDrills123456.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/df/CenterDrills123456.jpg/400px-CenterDrills123456.jpg 2x" data-file-width="1380" data-file-height="1416" /></a><figcaption>Center drill bits, numbers 1 to 6</figcaption></figure> <p><b>Center drill bits</b>, occasionally known as Slocombe drill bits, are used in <a href="/wiki/Metalworking" title="Metalworking">metalworking</a> to provide a starting hole for a larger-sized drill bit or to make a conical indentation in the end of a workpiece in which to mount a <a href="/wiki/Lathe_center" title="Lathe center">lathe center</a>. In either use, the name seems appropriate, as the bit is either establishing the <i>center</i> of a hole or making a conical hole for a lathe <i>center</i>. However, the true purpose of a center drill bit is the latter task, while the former task is best done with a <i>spotting drill bit</i> (as explained in detail below). Nevertheless, because of the frequent lumping together of both the terminology and the tool use, suppliers may call center drill bits <i>combined-drill-and-countersinks</i> in order to make it unambiguously clear what product is being ordered. They are numbered from 00 to 10 (smallest to largest). </p> <div class="mw-heading mw-heading4"><h4 id="Use_in_making_holes_for_lathe_centers">Use in making holes for lathe centers</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=13" title="Edit section: Use in making holes for lathe centers"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Center drill bits are meant to create a conical hole for "between centers" manufacturing processes (typically lathe or cylindrical-grinder work). That is, they provide a location for a (live, dead, or driven) center to locate the part about an axis. A workpiece machined between centers can be safely removed from one process (perhaps turning in a lathe) and set up in a later process (perhaps a <a href="/wiki/Grinding_(abrasive_cutting)" title="Grinding (abrasive cutting)">grinding</a> operation) with a negligible loss in the co-axiality of features (usually <a href="/wiki/Total_indicator_reading" title="Total indicator reading">total indicator reading</a> (TIR) less than 0.002 in (0.05 mm); and TIR < 0.0001 in (0.003 mm) is held in cylindrical grinding operations, as long as conditions are correct). </p> <div class="mw-heading mw-heading4"><h4 id="Use_in_spotting_hole_centers">Use in spotting hole centers</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=14" title="Edit section: Use in spotting hole centers"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Traditional twist drill bits may tend to wander when started on an unprepared surface. Once a bit wanders off course it is difficult to bring it back on center. A center drill bit frequently provides a reasonable starting point as it is short and therefore has a reduced tendency to wander when drilling is started. </p><p>While the above is a common use of center drill bits, it is a technically incorrect practice and should not be considered for production use. The correct tool to start a traditionally drilled hole (a hole drilled by a high-speed steel (HSS) twist drill bit) is a <i>spotting drill bit</i> (or a <i>spot drill bit</i>, as they are referenced in the U.S.). The included angle of the spotting drill bit should be the same as, or greater than, the conventional drill bit so that the drill bit will then start without undue stress on the bit's corners, which would cause premature failure of the bit and a loss of hole quality. </p><p>Most modern solid-carbide bits should not be used in conjunction with a spot drill bit or a center drill bit, as solid-carbide bits are specifically designed to start their own hole. Usually, spot drilling will cause premature failure of the solid-carbide bit and a certain loss of hole quality. If it is deemed necessary to <a href="/wiki/Chamfer" title="Chamfer">chamfer</a> a hole with a spot or center drill bit when a solid-carbide drill bit is used, it is best practice to do so after the hole is drilled.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2016)">citation needed</span></a></i>]</sup> </p><p>When drilling with a hand-held drill the flexibility of the bit is not the primary source of inaccuracy—it is the user's hands. Therefore, for such operations, a <a href="/wiki/Center_punch#Center" class="mw-redirect" title="Center punch">center punch</a> is often used to spot the hole center prior to drilling a <a href="/wiki/Pilot_hole" title="Pilot hole">pilot hole</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Core_drill_bit">Core drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=15" title="Edit section: Core drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:HSS_Core_drills.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/82/HSS_Core_drills.jpg/150px-HSS_Core_drills.jpg" decoding="async" width="150" height="119" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/82/HSS_Core_drills.jpg/225px-HSS_Core_drills.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/82/HSS_Core_drills.jpg/300px-HSS_Core_drills.jpg 2x" data-file-width="3689" data-file-height="2919" /></a><figcaption>HSS core drills in various sizes</figcaption></figure> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Magnetic_Drilling_Machine_from_BDS.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/00/Magnetic_Drilling_Machine_from_BDS.jpg/150px-Magnetic_Drilling_Machine_from_BDS.jpg" decoding="async" width="150" height="225" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/00/Magnetic_Drilling_Machine_from_BDS.jpg/225px-Magnetic_Drilling_Machine_from_BDS.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/00/Magnetic_Drilling_Machine_from_BDS.jpg/300px-Magnetic_Drilling_Machine_from_BDS.jpg 2x" data-file-width="2704" data-file-height="4064" /></a><figcaption>A magnetic core drilling machine making hole with annular cutter (core drill)</figcaption></figure> <p>The term <b>core drill bit</b> is used for two quite different tools. </p> <div class="mw-heading mw-heading4"><h4 id="Enlarging_holes">Enlarging holes</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=16" title="Edit section: Enlarging holes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A bit used to enlarge an existing hole is called a core drill bit. The existing hole may be the result of a <a href="/wiki/Core_(manufacturing)" title="Core (manufacturing)">core</a> from a <a href="/wiki/Casting" title="Casting">casting</a> or a stamped (punched) hole. The name comes from its first use, for drilling out the hole left by a <i>foundry core</i>, a cylinder placed in a mould for a casting that leaves an irregular hole in the product. This core drill bit is solid. </p><p>These core drill bits are similar in appearance to <a href="/wiki/Reamer" title="Reamer">reamers</a> as they have no cutting point or means of starting a hole. They have 3 or 4 flutes which enhances the finish of the hole and ensures the bit cuts evenly. Core drill bits differ from reamers in the amount of material they are intended to remove. A reamer is only intended to enlarge a hole a slight amount which, depending on the reamers size, may be anything from 0.1 millimeter to perhaps a millimeter. A core drill bit may be used to double the size of a hole. </p><p>Using an ordinary two-flute twist drill bit to enlarge the hole resulting from a casting core will not produce a clean result, the result will possibly be out of round, off center and generally of poor finish. The two fluted drill bit also has a tendency to grab on any protuberance (such as <a href="/wiki/Flash_(manufacturing)" title="Flash (manufacturing)">flash</a>) which may occur in the product. </p> <div class="mw-heading mw-heading4"><h4 id="Extracting_core">Extracting core</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=17" title="Edit section: Extracting core"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Annular_cutter" title="Annular cutter">Annular cutter</a></div> <p>A hollow cylindrical bit which will cut a hole with an <a href="/wiki/Annulus_(mathematics)" title="Annulus (mathematics)">annular</a> cross-section and leave the inner cylinder of material (the "core") intact, often removing it, is also called a core drill bit or <a href="/wiki/Annular_cutter" title="Annular cutter">annular cutter</a>. Unlike other drills, the purpose is often to retrieve the core rather than simply to make a hole. A diamond core drill bit is intended to cut an annular hole in the workpiece. Large bits of similar shape are used for geological work, where a deep hole is drilled in sediment or ice and the drill bit, which now contains an intact core of the material drilled with a diameter of several centimeters, is retrieved to allow study of the <a href="/wiki/Stratum" title="Stratum">strata</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Countersink_bit">Countersink bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=18" title="Edit section: Countersink bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Countersink" title="Countersink">Countersink</a></div> <p>A countersink is a conical hole cut into a manufactured object; a countersink bit (sometimes called simply countersink) is the cutter used to cut such a hole. A common use is to allow the head of a bolt or screw, with a shape exactly matching the countersunk hole, to sit flush with or below the surface of the surrounding material. (By comparison, a counterbore makes a flat-bottomed hole that might be used with a hex-headed capscrew.) A countersink may also be used to remove the burr left from a drilling or tapping operation. </p> <div class="mw-heading mw-heading3"><h3 id="Ejector_drill_bit">Ejector drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=19" title="Edit section: Ejector drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Used almost exclusively for deep hole drilling of medium to large diameter holes (approximately <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">3</span>⁄<span class="den">4</span></span>–4 in or 19–102 mm diameter). An ejector drill bit uses a specially designed carbide cutter at the point. The bit body is essentially a tube within a tube. Flushing water travels down between the two tubes. Chip removal is back through the center of the bit. </p> <div class="mw-heading mw-heading3"><h3 id="Gun_drill_bit">Gun drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=20" title="Edit section: Gun drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Gun_drill" title="Gun drill">Gun drill</a></div> <p>Gun drills are straight fluted drills which allow <a href="/wiki/Cutting_fluid" title="Cutting fluid">cutting fluid</a> (either compressed air or a suitable liquid) to be injected through the drill's hollow body to the cutting face. </p> <div class="mw-heading mw-heading3"><h3 id="Indexable_drill_bit">Indexable drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=21" title="Edit section: Indexable drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Indexable drill bits are primarily used in <a href="/wiki/CNC" class="mw-redirect" title="CNC">CNC</a> and other high precision or production equipment, and are the most expensive type of drill bit, costing the most per diameter and length. Like <a href="/wiki/Tool_bit" title="Tool bit">indexable lathe tools</a> and <a href="/wiki/Milling_cutter" title="Milling cutter">milling cutters</a>, they use replaceable carbide or ceramic inserts as a cutting face to alleviate the need for a tool grinder. One insert is responsible for the outer radius of the cut, and another insert is responsible for the inner radius. The tool itself handles the point deformity, as it is a low-wear task. The bit is hardened and coated against wear far more than the average drill bit, as the shank is non-consumable. Almost all indexable drill bits have multiple coolant channels for prolonged tool life under heavy usage. They are also readily available in odd configurations, such as straight flute, fast spiral, multiflute, and a variety of cutting face geometries. </p><p>Typically indexable drill bits are used in holes that are no deeper than about 5 times the bit diameter. They are capable of quite high axial loads and cut very fast. </p> <div class="mw-heading mw-heading3"><h3 id="Left-hand_bit">Left-hand bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=22" title="Edit section: Left-hand bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Left_hand_drill_bit.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/58/Left_hand_drill_bit.jpg/220px-Left_hand_drill_bit.jpg" decoding="async" width="220" height="81" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/58/Left_hand_drill_bit.jpg/330px-Left_hand_drill_bit.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/58/Left_hand_drill_bit.jpg/440px-Left_hand_drill_bit.jpg 2x" data-file-width="1707" data-file-height="627" /></a><figcaption>An 1/8 inch left-hand drill bit</figcaption></figure> <p>Left-hand bits are almost always twist bits and are predominantly used in the <a href="/wiki/Mass_production" title="Mass production">repetition</a> engineering industry on screw machines or drilling heads. Left-handed drill bits allow a machining operation to continue where either the spindle cannot be reversed or the design of the machine makes it more efficient to run left-handed. With the increased use of the more versatile CNC machines, their use is less common than when specialized machines were required for machining tasks. </p><p><a href="/wiki/Screw_extractor" title="Screw extractor">Screw extractors</a> are essentially left-hand bits of specialized shape, used to remove common right-hand <a href="/wiki/Screw" title="Screw">screws</a> whose heads are broken or too damaged to allow a screwdriver tip to engage, making use of a screwdriver impossible. The extractor is pressed against the damaged head and rotated counter-clockwise and will tend to jam in the damaged head and then turn the screw counter-clockwise, unscrewing it. For screws that break off deeper in the hole, an extractor set will often include left handed drill bits of the appropriate diameters so that grab holes can be drilled into the screws in a left handed direction, preventing further tightening of the broken piece. </p> <div class="mw-heading mw-heading3"><h3 id="Metal_spade_bit">Metal spade bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=23" title="Edit section: Metal spade bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A spade drill bit for metal is a two part bit with a tool holder and an insertable tip, called an insert. The inserts come in various sizes that range from <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">7</span>⁄<span class="den">16</span></span> to 2.5 inches (11 to 64 mm). The tool holder usually has a coolant passage running through it.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> They are capable of cutting to a depth of about 10 times the bit diameter. This type of drill bit can also be used to make stepped holes. </p> <div class="mw-heading mw-heading3"><h3 id="Straight_fluted_bit">Straight fluted bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=24" title="Edit section: Straight fluted bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Straight fluted drill bits do not have a helical twist like twist drill bits do. They are used when drilling <a href="/wiki/Copper" title="Copper">copper</a> or <a href="/wiki/Brass" title="Brass">brass</a> because they have less of a tendency to "dig in" or grab the material. </p> <div class="mw-heading mw-heading3"><h3 id="Trepan">Trepan</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=25" title="Edit section: Trepan"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Trepanning_(drilling)" class="mw-redirect" title="Trepanning (drilling)">Trepanning (drilling)</a> and <a href="/wiki/Cranial_drill" title="Cranial drill">Cranial drill</a></div> <p>A trepan, sometimes called a BTA drill bit (after the Boring and Trepanning Association), is a drill bit that cuts an annulus and leaves a center core. Trepans usually have multiple carbide inserts and rely on water to cool the cutting tips and to flush chips out of the hole. Trepans are often used to cut large diameters and deep holes. Typical bit diameters are 6–14 in (150–360 mm) and hole depth from 12 in (300 mm) up to 71 feet (22 m). </p> <div class="mw-heading mw-heading2"><h2 id="For_wood">For wood</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=26" title="Edit section: For wood"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Brad_point_bit">Brad point bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=27" title="Edit section: Brad point bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Drill_tip_spur.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/25/Drill_tip_spur.jpg/200px-Drill_tip_spur.jpg" decoding="async" width="200" height="149" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/25/Drill_tip_spur.jpg/300px-Drill_tip_spur.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/25/Drill_tip_spur.jpg/400px-Drill_tip_spur.jpg 2x" data-file-width="774" data-file-height="576" /></a><figcaption>A 10.5 mm brad point drill bit</figcaption></figure> <p>The <b>brad point drill bit</b> (also known as <b>lip and spur drill bit</b>, and <b>dowel drill bit</b>) is a variation of the <a href="#Twist_drill_bit">twist drill bit</a> which is optimized for drilling in wood. </p><p>Conventional twist drill bits tend to wander when presented to a flat workpiece. For metalwork, this is countered by drilling a pilot hole with a spotting drill bit. In wood, the brad point drill bit is another solution: the center of the drill bit is given not the straight chisel of the twist drill bit, but a spur with a sharp point, and four sharp corners to cut the wood. While drilling, the sharp point of the spur pushes into the soft wood to keep the drill bit in line. </p><p>Metals are typically <a href="/wiki/Isotropic" class="mw-redirect" title="Isotropic">isotropic</a>, so even an ordinary twist drill bit will shear the edges of the hole cleanly. <i>Wood</i> drilled across the grain, however, produces long strands of wood fiber. These long strands tend to pull out of the hole, rather than being cleanly cut at the hole edge. The brad point drill bit has the outside corner of the cutting edges leading, so that it cuts the periphery of the hole before the inner parts of the cutting edges plane off the base of the hole. By cutting the periphery first, the lip maximizes the chance that the fibers can be cut cleanly, rather than having to be pulled messily from the timber. </p><p>Brad point drill bits are also effective in soft plastic. When using conventional twist drill bits in a handheld drill, where the drilling direction is not maintained perfectly throughout the operation, there is a tendency for hole edges to be "smeared" due to side friction and heat. </p><p>In metal, the brad point drill bit is confined to drilling only the thinnest and softest <a href="/wiki/Sheet_metal" title="Sheet metal">sheet metals</a>, ideally with a <a href="/wiki/Drill_press" title="Drill press">drill press</a>. The bits have an extremely fast cutting tool geometry: no point angle, combined with a large (considering the flat cutting edge) lip angle, causes the edges to take a very aggressive cut with relatively little point pressure. This means these bits tend to bind in metal; given a workpiece of sufficient thinness, they have a tendency to punch through and leave the bit's cross-sectional geometry behind. </p><p>Brad point drill bits are ordinarily available in diameters from 3–16 mm (0.12–0.63 in). </p> <div class="mw-heading mw-heading3"><h3 id="Wood_spade_bit">Wood spade bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=28" title="Edit section: Wood spade bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Spade bits are used for rough boring in wood. They tend to cause splintering when they emerge from the workpiece. Woodworkers avoid splintering by finishing the hole from the opposite side of the work. Spade bits are flat, with a centering point and two cutters. The cutters are often equipped with spurs in an attempt to ensure a cleaner hole. With their small shank diameters relative to their boring diameters, spade bit shanks often have flats forged or ground into them to prevent slipping in drill chucks. Some bits are equipped with long shanks and have a small hole drilled through the flat part, allowing them to be used much like a <a class="mw-selflink-fragment" href="#Installer_bit">bell-hanger bit</a>. Intended for high speed use, they are used with electric hand drills. Spade bits are also sometimes referred to as "paddle bits". </p><p>Spade drill bits are ordinarily available in diameters from 6 to 36 mm, or <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">4</span></span> to <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac">1<span class="sr-only">+</span><span class="num">1</span>⁄<span class="den">2</span></span> inches. </p> <ul class="gallery mw-gallery-traditional"> <li class="gallerybox" style="width: 355px"> <div class="thumb" style="width: 350px; height: 210px;"><span typeof="mw:File"><a href="/wiki/File:Spade_bits.JPG" class="mw-file-description" title="Spade bits"><img alt="Spade bits" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a9/Spade_bits.JPG/320px-Spade_bits.JPG" decoding="async" width="320" height="170" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a9/Spade_bits.JPG/480px-Spade_bits.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a9/Spade_bits.JPG/640px-Spade_bits.JPG 2x" data-file-width="1833" data-file-height="976" /></a></span></div> <div class="gallerytext">Spade bits</div> </li> <li class="gallerybox" style="width: 355px"> <div class="thumb" style="width: 350px; height: 210px;"><span typeof="mw:File"><a href="/wiki/File:Drill_spade_tiny.jpg" class="mw-file-description" title="Tiny spade bit"><img alt="Tiny spade bit" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Drill_spade_tiny.jpg/319px-Drill_spade_tiny.jpg" decoding="async" width="319" height="180" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Drill_spade_tiny.jpg/478px-Drill_spade_tiny.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Drill_spade_tiny.jpg/638px-Drill_spade_tiny.jpg 2x" data-file-width="669" data-file-height="378" /></a></span></div> <div class="gallerytext">Tiny spade bit</div> </li> </ul> <div class="mw-heading mw-heading3"><h3 id="Spoon_bit">Spoon bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=29" title="Edit section: Spoon bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Spoon bits consist of a grooved shank with a point shaped somewhat like the bowl of a spoon, with the cutting edge on the end. The more common type is like a gouge bit that ends in a slight point. This is helpful for starting the hole, as it has a center that will not wander or walk. These bits are used by chair-makers for boring or reaming holes in the seats and arms of chairs. Their design is ancient, going back to Roman times. Spoon bits have even been found in Viking excavations. Modern spoon bits are made of hand-forged carbon steel, carefully heat-treated and then hand ground to a fine edge. </p><p>Spoon bits are the traditional boring tools used with a brace. They should never be used with a power drill of any kind. Their key advantage over regular brace bits and power drill bits is that the angle of the hole can be adjusted. This is very important in chairmaking, because all the angles are usually eyeballed. Another advantage is that they do not have a lead screw, so they can be drilled successfully in a chair leg without having the lead screw peek out the other side. </p><p>When reaming a pre-bored straight-sided hole, the spoon bit is inserted into the hole and rotated in a clockwise direction with a carpenters' brace until the desired taper is achieved. When boring into solid wood, the bit should be started in the vertical position; after a "dish" has been created and the bit has begun to "bite" into the wood, the angle of boring can be changed by tilting the brace a bit out of the vertical. Holes can be drilled precisely, cleanly and quickly in any wood, at any angle of incidence, with total control of direction and the ability to change that direction at will. </p><p>Parallel spoon bits are used primarily for boring holes in the seat of a <a href="/wiki/Windsor_chair" title="Windsor chair">Windsor chair</a> to take the back spindles, or similar round-tenon work when assembling furniture frames in <a href="/wiki/Green_woodworking" title="Green woodworking">green woodworking</a> work. </p><p>The spoon bit may be honed by using a slipstone on the inside of the cutting edge; the outside edge should never be touched. </p> <div class="mw-heading mw-heading3"><h3 id="Forstner_bit">Forstner bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=30" title="Edit section: Forstner bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Drill_tip_forstner.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Drill_tip_forstner.jpg/220px-Drill_tip_forstner.jpg" decoding="async" width="220" height="217" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Drill_tip_forstner.jpg/330px-Drill_tip_forstner.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0f/Drill_tip_forstner.jpg/440px-Drill_tip_forstner.jpg 2x" data-file-width="618" data-file-height="609" /></a><figcaption>25 mm (1.0 in) Forstner bit</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Forstner_Bohrer_01.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/57/Forstner_Bohrer_01.jpg/220px-Forstner_Bohrer_01.jpg" decoding="async" width="220" height="199" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/57/Forstner_Bohrer_01.jpg/330px-Forstner_Bohrer_01.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/57/Forstner_Bohrer_01.jpg/440px-Forstner_Bohrer_01.jpg 2x" data-file-width="1990" data-file-height="1798" /></a><figcaption>Another Forstner bit</figcaption></figure> <p>Forstner bits were patented by <a href="/wiki/Benjamin_Forstner" title="Benjamin Forstner">Benjamin Forstner</a> in 1886.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> They bore precise, flat-bottomed holes in wood, in any orientation with respect to the wood grain. They can cut on the edge of a block of wood, and can cut overlapping holes; for such applications they are normally used in drill presses or lathes rather than in hand-held electric drills. Because of the flat bottom of the hole, they are useful for drilling through veneer already glued to add an inlay. </p><p>The bit includes a center <a href="#Brad_point_bit">brad point</a> which guides it throughout the cut (and incidentally spoils the otherwise flat bottom of the hole). The cylindrical cutter around the perimeter shears the wood fibers at the edge of the bore, and also helps guide the bit into the material more precisely. Forstner bits have radial cutting edges to plane off the material at the bottom of the hole. The bits shown in the images have two radial edges; other designs may have more. Forstner bits have no mechanism to clear chips from the hole, and therefore must be pulled out periodically. </p><p>Sawtooth bits are also available, which include many more cutting edges to the cylinder. These cut faster, but produce a more ragged hole. They have advantages over Forstner bits when boring into <a href="/wiki/End_grain" class="mw-redirect" title="End grain">end grain</a>. </p><p>Bits are commonly available in sizes from 8–50 mm (0.3–2.0 in) diameter. Sawtooth bits are available up to 100 mm (4 in) diameter. </p><p>Originally the Forstner bit was very successful with gunsmiths because of its ability to drill an exceedingly smooth-sided hole.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2022)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading3"><h3 id="Center_bit">Center bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=31" title="Edit section: Center bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The center bit is optimized for drilling in wood with a <a href="/wiki/Brace_(tool)" title="Brace (tool)">hand brace</a>. Many different designs have been produced. </p><p>The center of the bit is a tapered screw thread. This screws into the wood as the bit is turned, and pulls the bit into the wood. There is no need for any force to push the bit into the workpiece, only the torque to turn the bit. This is ideal for a bit for a hand tool. The radial cutting edges remove a slice of wood of thickness equal to the pitch of the central screw for each rotation of the bit. To pull the bit from the hole, either the female thread in the wood workpiece must be stripped, or the rotation of the bit must be reversed. </p><p>The edge of the bit has a sharpened spur to cut the fibers of the wood, as in the brad point drill bit. A radial cutting edge planes the wood from the base of the hole. In this version, there is minimal or no spiral to remove chips from the hole. The bit must be periodically withdrawn to clear the chips. </p><p>Some versions have two spurs. Some have two radial cutting edges. </p><p>Center bits do not cut well in the end grain of wood. The central screw tends to pull out, or to split the wood along the grain, and the radial edges have trouble cutting through the long wood fibers. </p><p>Center bits are made of relatively soft steel, and can be sharpened with a file. </p> <ul class="gallery mw-gallery-traditional"> <li class="gallerybox" style="width: 365px"> <div class="thumb" style="width: 360px; height: 280px;"><span typeof="mw:File"><a href="/wiki/File:Drill_brace.jpg" class="mw-file-description" title="A 19 mm (3/4 inch) center bit, made sometime before 1950"><img alt="A 19 mm (3/4 inch) center bit, made sometime before 1950" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/16/Drill_brace.jpg/330px-Drill_brace.jpg" decoding="async" width="330" height="151" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/16/Drill_brace.jpg/495px-Drill_brace.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/16/Drill_brace.jpg/660px-Drill_brace.jpg 2x" data-file-width="1368" data-file-height="627" /></a></span></div> <div class="gallerytext">A 19 mm (3/4 inch) center bit, made sometime before 1950</div> </li> <li class="gallerybox" style="width: 365px"> <div class="thumb" style="width: 360px; height: 280px;"><span typeof="mw:File"><a href="/wiki/File:Drill_tip_brace.jpg" class="mw-file-description" title="Center bit tip detail"><img alt="Center bit tip detail" src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c3/Drill_tip_brace.jpg/233px-Drill_tip_brace.jpg" decoding="async" width="233" height="250" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c3/Drill_tip_brace.jpg/349px-Drill_tip_brace.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c3/Drill_tip_brace.jpg/466px-Drill_tip_brace.jpg 2x" data-file-width="609" data-file-height="654" /></a></span></div> <div class="gallerytext">Center bit tip detail</div> </li> </ul> <div class="mw-heading mw-heading3"><h3 id="Auger_bit">Auger bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=32" title="Edit section: Auger bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Further information: <a href="/wiki/Auger_(drill)" class="mw-redirect" title="Auger (drill)">Auger (drill)</a></div> <p>The cutting principles of the auger bit are the same as those of the center bit above. The auger adds a long deep spiral flute for effective chip removal. </p><p>Two styles of auger bit are commonly used in hand braces: the <b>Jennings</b> or Jennings-pattern bit has a self-feeding screw tip, two spurs and two radial cutting edges. This bit has a double flute starting from the cutting edges, and extending several inches up the shank of the bit, for waste removal. This pattern of bit was developed by Russell Jennings in the mid-19th century. </p><p>The <b>Irwin</b> or solid-center auger bit is similar, the only difference being that one of the cutting edges has only a "vestigal flute" supporting it, which extends only about <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">1</span>⁄<span class="den">2</span></span> in (13 mm) up the shank before ending. The other flute continues full-length up the shank for waste removal. The Irwin bit may afford greater space for waste removal, greater strength (because the design allows for a center shank of increased size within the flutes, as compared to the Jenning bits), or smaller manufacturing costs. This style of bit was invented in 1884, and the rights sold to Charles Irwin who patented and marketed this pattern the following year. </p><p>Both styles of auger bits were manufactured by several companies throughout the early- and mid-20th century, and are still available new from select sources today. </p><p>The diameter of auger bits for hand braces is commonly expressed by a single number, indicating the size in 16ths of an inch. For example, #4 is 4/16 or 1/4 in (6 mm), #6 is 6/16 or 3/8 in (9 mm), #9 is 9/16 in (14 mm), and #16 is 16/16 or 1 in (25 mm). Sets commonly consist of #4-16 or #4-10 bits. </p><p>The bit shown in the picture is a modern design for use in portable power tools, made in the UK in about 1995. It has a single spur, a single radial cutting edge and a single flute. Similar auger bits are made with diameters from 6 mm (3/16 in) to 30 mm (1 3/16 in). Augers up to 600 mm (2.0 ft) long are available, where the chip-clearing capability is especially valuable for drilling deep holes. </p> <ul class="gallery mw-gallery-traditional"> <li class="gallerybox" style="width: 355px"> <div class="thumb" style="width: 350px; height: 200px;"><span typeof="mw:File"><a href="/wiki/File:Drill_auger.jpg" class="mw-file-description" title="20 mm (0.79 in) auger bit for wood"><img alt="20 mm (0.79 in) auger bit for wood" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/96/Drill_auger.jpg/320px-Drill_auger.jpg" decoding="async" width="320" height="153" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/96/Drill_auger.jpg/480px-Drill_auger.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/96/Drill_auger.jpg/640px-Drill_auger.jpg 2x" data-file-width="951" data-file-height="456" /></a></span></div> <div class="gallerytext">20 mm (0.79 in) auger bit for wood</div> </li> <li class="gallerybox" style="width: 355px"> <div class="thumb" style="width: 350px; height: 200px;"><span typeof="mw:File"><a href="/wiki/File:Drill_tip_auger.jpg" class="mw-file-description" title="Auger bit tip detail"><img alt="Auger bit tip detail" src="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/Drill_tip_auger.jpg/227px-Drill_tip_auger.jpg" decoding="async" width="227" height="170" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/Drill_tip_auger.jpg/340px-Drill_tip_auger.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/59/Drill_tip_auger.jpg/453px-Drill_tip_auger.jpg 2x" data-file-width="1080" data-file-height="810" /></a></span></div> <div class="gallerytext">Auger bit tip detail</div> </li> </ul> <div class="mw-heading mw-heading3"><h3 id="Gimlet_bit">Gimlet bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=33" title="Edit section: Gimlet bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The gimlet bit is a very old design. The bit is the same style as that used in the <a href="/wiki/Gimlet_(tool)" title="Gimlet (tool)">gimlet</a>, a self-contained tool for boring small holes in wood by hand. Since about 1850, gimlets have had a variety of cutter designs, but some are still produced with the original version. The gimlet bit is intended to be used in a hand brace for drilling into wood. It is the usual style of bit for use in a brace for holes below about 7 mm (0.28 in) diameter. </p><p>The tip of the gimlet bit acts as a tapered screw, to draw the bit into the wood and to begin forcing aside the wood fibers, without necessarily cutting them. The cutting action occurs at the side of the broadest part of the cutter. Most drill bits cut the base of the hole. The gimlet bit cuts the side of the hole. </p> <ul class="gallery mw-gallery-traditional"> <li class="gallerybox" style="width: 365px"> <div class="thumb" style="width: 360px; height: 210px;"><span typeof="mw:File"><a href="/wiki/File:Drill_gimlet.jpg" class="mw-file-description" title="Gimlet bit for wood, made sometime before 1950."><img alt="Gimlet bit for wood, made sometime before 1950." src="//upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Drill_gimlet.jpg/330px-Drill_gimlet.jpg" decoding="async" width="330" height="175" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Drill_gimlet.jpg/495px-Drill_gimlet.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Drill_gimlet.jpg/660px-Drill_gimlet.jpg 2x" data-file-width="1185" data-file-height="630" /></a></span></div> <div class="gallerytext">Gimlet bit for wood, made sometime before 1950.</div> </li> <li class="gallerybox" style="width: 365px"> <div class="thumb" style="width: 360px; height: 210px;"><span typeof="mw:File"><a href="/wiki/File:Drill_tip_gimlet.jpg" class="mw-file-description" title="Gimlet bit tip detail"><img alt="Gimlet bit tip detail" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/9b/Drill_tip_gimlet.jpg/263px-Drill_tip_gimlet.jpg" decoding="async" width="263" height="180" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/9b/Drill_tip_gimlet.jpg/395px-Drill_tip_gimlet.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/9b/Drill_tip_gimlet.jpg/526px-Drill_tip_gimlet.jpg 2x" data-file-width="903" data-file-height="618" /></a></span></div> <div class="gallerytext">Gimlet bit tip detail</div> </li> </ul> <div class="mw-heading mw-heading3"><h3 id="Hinge_sinker_bit">Hinge sinker bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=34" title="Edit section: Hinge sinker bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Drill_tip_30mm_hinge.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Drill_tip_30mm_hinge.jpg/200px-Drill_tip_30mm_hinge.jpg" decoding="async" width="200" height="152" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Drill_tip_30mm_hinge.jpg/300px-Drill_tip_30mm_hinge.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Drill_tip_30mm_hinge.jpg/400px-Drill_tip_30mm_hinge.jpg 2x" data-file-width="930" data-file-height="705" /></a><figcaption>30 mm hinge sinker bit</figcaption></figure> <p>The hinge sinker bit is an example of a custom drill bit design for a specific application. Many European kitchen cabinets are made from <a href="/wiki/Particle_board" title="Particle board">particle board</a> or <a href="/wiki/Medium-density_fiberboard" class="mw-redirect" title="Medium-density fiberboard">medium-density fiberboard</a> (MDF) with a laminated <a href="/wiki/Melamine_resin" title="Melamine resin">melamine resin</a> veneer. Those types of <a href="/wiki/Pressed_wood" title="Pressed wood">pressed wood</a> boards are not very strong, and the screws of butt <a href="/wiki/Hinge" title="Hinge">hinges</a> tend to pull out. A specialist hinge has been developed which uses the walls of a 35 mm-diameter (1.4 in) hole, bored in the particle board, for support. This is a very common and relatively successful construction method. </p><p>A Forstner bit could bore the mounting hole for the hinge, but particle board and MDF are very abrasive materials, and steel cutting edges soon wear. A <a href="/wiki/Tungsten_carbide" title="Tungsten carbide">tungsten carbide</a> cutter is needed, but the complex shape of a forstner bit is difficult to manufacture in carbide, so this special drill bit with a simpler shape is commonly used. It has cutting edges of tungsten carbide brazed to a steel body; a center spur keeps the bit from wandering. </p> <div class="mw-heading mw-heading3"><h3 id="Adjustable_wood_bits">Adjustable wood bits</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=35" title="Edit section: Adjustable wood bits"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Adjustable_drill_bit_closeup.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/88/Adjustable_drill_bit_closeup.jpg/200px-Adjustable_drill_bit_closeup.jpg" decoding="async" width="200" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/88/Adjustable_drill_bit_closeup.jpg/300px-Adjustable_drill_bit_closeup.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/88/Adjustable_drill_bit_closeup.jpg/400px-Adjustable_drill_bit_closeup.jpg 2x" data-file-width="1984" data-file-height="1488" /></a><figcaption>An adjustable wood bit meant for use in a <a href="/wiki/Brace_(tool)" title="Brace (tool)">brace</a></figcaption></figure> <p>An adjustable wood bit, also known as an expansive wood bit, has a small center pilot bit with an adjustable, sliding cutting edge mounted above it, usually containing a single sharp point at the outside, with a <a href="/wiki/Set_screw" title="Set screw">set screw</a> to lock the cutter in position. When the cutting edge is centered on the bit, the hole drilled will be small, and when the cutting edge is slid outwards, a larger hole is drilled. This allows a single drill bit to drill a wide variety of holes, and can take the place of a large, heavy set of different size bits, as well as providing uncommon bit sizes. A <a href="/wiki/Ruler" title="Ruler">ruler</a> or <a href="/wiki/Vernier_scale" title="Vernier scale">vernier scale</a> is usually provided to allow precise adjustment of the bit size. </p><p>These bits are available both in a version similar to an auger bit or brace bit, designed for low speed, high torque use with a brace or other hand drill (pictured to the right), or as a high speed, low torque bit meant for a power drill. While the shape of the cutting edges is different, and one uses screw threads and the other a twist bit for the pilot, the method of adjusting them remains the same. </p> <div class="mw-heading mw-heading2"><h2 id="Other_materials">Other materials</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=36" title="Edit section: Other materials"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Diamond_core_bit">Diamond core bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=37" title="Edit section: Diamond core bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Diamond_core_drill_bit" class="mw-redirect" title="Diamond core drill bit">Diamond core drill bit</a></div> <p>The diamond masonry mortar bit is a hybrid drill bit, designed to work as a combination router and drill bit. It consists of a steel shell, with the diamonds embedded in metal segments attached to the cutting edge. These drill bits are used at relatively low speeds. </p> <div class="mw-heading mw-heading3"><h3 id="Masonry_drill_bit">Masonry drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=38" title="Edit section: Masonry drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The masonry bit shown here is a variation of the twist drill bit. The bulk of the tool is a relatively soft steel, and is machined with a <a href="/wiki/Milling_machine" class="mw-redirect" title="Milling machine">mill</a> rather than ground. An insert of <a href="/wiki/Tungsten_carbide" title="Tungsten carbide">tungsten carbide</a> is <a href="/wiki/Brazing" title="Brazing">brazed</a> into the steel to provide the cutting edges. </p><p>Masonry bits typically are used with a <a href="/wiki/Hammer_drill" title="Hammer drill">hammer drill</a>, which hammers the bit into the material being drilled as it rotates; the hammering breaks up the masonry at the drill bit tip, and the rotating flutes carry away the dust. Rotating the bit also brings the cutting edges onto a fresh portion of the hole bottom with every hammer blow. Hammer drill bits often use special shank shapes such as the <a href="/wiki/Drill_bit_shank#SDS_shank" title="Drill bit shank">SDS</a> type, which allows the bit to slide within the chuck when hammering, without the whole heavy chuck executing the hammering motion. </p><p>Masonry bits of the style shown are commonly available in diameters from 3 mm to 40 mm. For larger diameters, core bits are used. Masonry bits up to 1,000 mm (39 in) long can be used with hand-portable power tools, and are very effective for installing wiring and plumbing in existing buildings. </p><p>A <b><style data-mw-deduplicate="TemplateStyles:r1238216509">.mw-parser-output .vanchor>:target~.vanchor-text{background-color:#b1d2ff}@media screen{html.skin-theme-clientpref-night .mw-parser-output .vanchor>:target~.vanchor-text{background-color:#0f4dc9}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .vanchor>:target~.vanchor-text{background-color:#0f4dc9}}</style><span class="vanchor"><span id="star_drill_bit"></span><span class="vanchor-text">star drill bit</span></span></b>, similar in appearance and function to a hole punch or chisel, is used as a hand powered drill in conjunction with a <a href="/wiki/Hammer" title="Hammer">hammer</a> to drill into <a href="/wiki/Rock_(geology)" title="Rock (geology)">stone</a> and <a href="/wiki/Masonry" title="Masonry">masonry</a>. A star drill bit's cutting edge consists of several blades joined at the center to form a star pattern. </p> <ul class="gallery mw-gallery-packed"> <li class="gallerybox" style="width: 284.66666666667px"> <div class="thumb" style="width: 282.66666666667px;"><span typeof="mw:File"><a href="/wiki/File:Drill_masonry.jpg" class="mw-file-description" title="25×500 mm SDS-plus masonry bit"><img alt="25×500 mm SDS-plus masonry bit" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Drill_masonry.jpg/424px-Drill_masonry.jpg" decoding="async" width="283" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Drill_masonry.jpg/635px-Drill_masonry.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Drill_masonry.jpg/847px-Drill_masonry.jpg 2x" data-file-width="1185" data-file-height="504" /></a></span></div> <div class="gallerytext">25×500 mm <a href="/wiki/Chuck_(engineering)#Special_Direct_System_(SDS)" title="Chuck (engineering)">SDS-plus</a> masonry bit</div> </li> <li class="gallerybox" style="width: 169.33333333333px"> <div class="thumb" style="width: 167.33333333333px;"><span typeof="mw:File"><a href="/wiki/File:Drill_tip_masonry.jpg" class="mw-file-description" title="Masonry bit tip"><img alt="Masonry bit tip" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/95/Drill_tip_masonry.jpg/251px-Drill_tip_masonry.jpg" decoding="async" width="168" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/95/Drill_tip_masonry.jpg/376px-Drill_tip_masonry.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/95/Drill_tip_masonry.jpg/502px-Drill_tip_masonry.jpg 2x" data-file-width="1062" data-file-height="762" /></a></span></div> <div class="gallerytext">Masonry bit tip</div> </li> <li class="gallerybox" style="width: 114px"> <div class="thumb" style="width: 112px;"><span typeof="mw:File"><a href="/wiki/File:Quadro40max.JPG" class="mw-file-description" title="Rebar resistant bit with four carbide cutters"><img alt="Rebar resistant bit with four carbide cutters" src="//upload.wikimedia.org/wikipedia/commons/thumb/2/24/Quadro40max.JPG/168px-Quadro40max.JPG" decoding="async" width="112" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/24/Quadro40max.JPG/252px-Quadro40max.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/24/Quadro40max.JPG/336px-Quadro40max.JPG 2x" data-file-width="670" data-file-height="718" /></a></span></div> <div class="gallerytext">Rebar resistant bit with four carbide cutters</div> </li> <li class="gallerybox" style="width: 182px"> <div class="thumb" style="width: 180px;"><span typeof="mw:File"><a href="/wiki/File:Star_drill2.jpg" class="mw-file-description" title="Star drill"><img alt="Star drill" src="//upload.wikimedia.org/wikipedia/commons/thumb/7/73/Star_drill2.jpg/270px-Star_drill2.jpg" decoding="async" width="180" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/73/Star_drill2.jpg/405px-Star_drill2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/73/Star_drill2.jpg/540px-Star_drill2.jpg 2x" data-file-width="1597" data-file-height="1065" /></a></span></div> <div class="gallerytext">Star drill</div> </li> </ul> <div class="mw-heading mw-heading3"><h3 id="Glass_drill_bit">Glass drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=39" title="Edit section: Glass drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Glass bits have a spade-shaped carbide point. They generate high temperatures and have a very short life. Holes are generally drilled at low speed with a succession of increasing bit sizes. Diamond drill bits can also be used to cut holes in glass, and last much longer. </p> <div class="mw-heading mw-heading3"><h3 id="Ceramic_drill_bit">Ceramic drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=40" title="Edit section: Ceramic drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Ceramic drill bits are made to drill through glazed and unglazed ceramic tiles, for instance for installing bathroom fittings. </p> <div class="mw-heading mw-heading3"><h3 id="PCB_through-hole_drill_bit">PCB through-hole drill bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=41" title="Edit section: PCB through-hole drill bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A great number of holes with small diameters of about 1 mm or less must be drilled in <a href="/wiki/Printed_circuit_board" title="Printed circuit board">printed circuit boards</a> (PCBs) used by <a href="/wiki/Electronic_equipment" class="mw-redirect" title="Electronic equipment">electronic equipment</a> with <a href="/wiki/Through-hole" class="mw-redirect" title="Through-hole">through-hole</a> components. Most PCBs are made of highly abrasive <a href="/wiki/Fiberglass" title="Fiberglass">fiberglass</a>, which quickly wears steel bits, especially given the hundreds or thousands of holes on most circuit boards. To solve this problem, solid <a href="/wiki/Tungsten_carbide" title="Tungsten carbide">tungsten carbide</a> twist bits, which drill quickly through the board while providing a moderately long life, are almost always used. Carbide PCB bits are estimated to outlast high-speed steel bits by a factor of ten or more. Other options sometimes used are diamond or diamond-coated bits. </p><p>In industry, virtually all drilling is done by <a href="/wiki/Computer_numerical_control" class="mw-redirect" title="Computer numerical control">automated machines</a>, and the bits are often automatically replaced by the equipment as they wear, as even solid carbide bits do not last long in constant use. PCB bits, of narrow diameter, typically mount in a <a href="/wiki/Collet" title="Collet">collet</a> rather than a <a href="/wiki/Chuck_(engineering)" title="Chuck (engineering)">chuck</a>, and come with standard-size shanks, often with pre-installed stops to set them at an exact depth every time when being automatically chucked by the equipment. </p><p>Very high rotational speeds—30,000 to 100,000 <a href="/wiki/Revolutions_per_minute" title="Revolutions per minute">RPM</a> or even higher—are used; this translates to a reasonably fast linear speed of the cutting tip in these very small diameters. The high speed, small diameter, and the brittleness of the material, make the bits very vulnerable to breaking, particularly if the angle of the bit to the workpiece changes at all, or the bit contacts any object. Drilling by hand is not practical, and many general-purpose drilling machines designed for larger bits rotate too slowly and wobble too much to use carbide bits effectively. </p><p>Resharpened and easily available PCB drills have historically been used in many prototyping and home PCB labs, using a high-speed rotary tool for small-diameter bits (such as a Moto-Tool by Dremel) in a stiff drill-press jig. If used for other materials these tiny bits must be evaluated for equivalent cutting speed vs material resistance to the cut (hardness), as the bit's <a href="/wiki/Rake_angle" title="Rake angle">rake angle</a> and expected feed per revolution are optimised for high-speed automated use on fiberglass PCB substrate. </p> <ul class="gallery mw-gallery-traditional"> <li class="gallerybox" style="width: 335px"> <div class="thumb" style="width: 330px; height: 230px;"><span typeof="mw:File"><a href="/wiki/File:Two_pcb_bits.jpg" class="mw-file-description" title="Two PCB drill bits."><img alt="Two PCB drill bits." src="//upload.wikimedia.org/wikipedia/commons/thumb/3/33/Two_pcb_bits.jpg/141px-Two_pcb_bits.jpg" decoding="async" width="141" height="200" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/33/Two_pcb_bits.jpg/212px-Two_pcb_bits.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/33/Two_pcb_bits.jpg/282px-Two_pcb_bits.jpg 2x" data-file-width="300" data-file-height="425" /></a></span></div> <div class="gallerytext">Two <a href="/wiki/Printed_circuit_board" title="Printed circuit board">PCB</a> drill bits.</div> </li> <li class="gallerybox" style="width: 335px"> <div class="thumb" style="width: 330px; height: 230px;"><span typeof="mw:File"><a href="/wiki/File:Box_of_02in_pcb_bits.jpg" class="mw-file-description" title="A box of #76 (0.02 in or 0.51 mm) PCB drill bits."><img alt="A box of #76 (0.02 in or 0.51 mm) PCB drill bits." src="//upload.wikimedia.org/wikipedia/commons/thumb/d/db/Box_of_02in_pcb_bits.jpg/267px-Box_of_02in_pcb_bits.jpg" decoding="async" width="267" height="200" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/db/Box_of_02in_pcb_bits.jpg/400px-Box_of_02in_pcb_bits.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/db/Box_of_02in_pcb_bits.jpg/533px-Box_of_02in_pcb_bits.jpg 2x" data-file-width="1600" data-file-height="1200" /></a></span></div> <div class="gallerytext">A box of <a href="/wiki/Drill_bit_sizes" title="Drill bit sizes">#76</a> (0.02 in or 0.51 mm) <a href="/wiki/Printed_circuit_board" title="Printed circuit board">PCB</a> drill bits.</div> </li> </ul> <div class="mw-heading mw-heading3"><h3 id="Installer_bit">Installer bit</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=42" title="Edit section: Installer bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading4"><h4 id="Fishing_bit">Fishing bit</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=43" title="Edit section: Fishing bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Installer bits, also known as <b>bell-hanger</b> bits or <b>fishing</b> bits, are a type of twist drill bit for use with a hand-portable power tool. The key distinguishing feature of an installer bit is a transverse hole drilled through the web of the bit near the tip. Once the bit has penetrated a wall, a wire can be threaded through the hole and the bit pulled back out, pulling the wire with it. The wire can then be used to pull a cable or pipe back through the wall. This is especially helpful where the wall has a large cavity, where threading a <a href="/wiki/Fish_tape" title="Fish tape">fish tape</a> could be difficult. Some installer bits have a transverse hole drilled at the shank end as well. Once a hole has been drilled, the wire can be threaded through the shank end, the bit released from the chuck, and all pulled forward through the drilled hole. These bits are made for cement, block and brick; they are not for drilling into wood. Sinclair Smith of <a href="/wiki/Brooklyn,_New_York" class="mw-redirect" title="Brooklyn, New York">Brooklyn, New York</a> was issued <span><a rel="nofollow" class="external text" href="https://patents.google.com/patent/US597750">U.S. patent 597,750</a></span> for this invention on January 25, 1898. </p><p>Installer bits are available in various materials and styles for drilling wood, masonry and metal. </p> <ul class="gallery mw-gallery-traditional"> <li class="gallerybox" style="width: 335px"> <div class="thumb" style="width: 330px; height: 210px;"><span typeof="mw:File"><a href="/wiki/File:Installer_bit_overview.jpg" class="mw-file-description" title="A 3⁄8 in × 18 in (9.5 mm × 457.2 mm) installer bit"><img alt="A 3⁄8 in × 18 in (9.5 mm × 457.2 mm) installer bit" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/87/Installer_bit_overview.jpg/240px-Installer_bit_overview.jpg" decoding="async" width="240" height="180" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/87/Installer_bit_overview.jpg/360px-Installer_bit_overview.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/87/Installer_bit_overview.jpg/480px-Installer_bit_overview.jpg 2x" data-file-width="1984" data-file-height="1488" /></a></span></div> <div class="gallerytext">A <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1154941027"><span class="frac"><span class="num">3</span>⁄<span class="den">8</span></span> in × 18 in (9.5 mm × 457.2 mm) installer bit</div> </li> <li class="gallerybox" style="width: 335px"> <div class="thumb" style="width: 330px; height: 210px;"><span typeof="mw:File"><a href="/wiki/File:Installer_bit_closeup_2.jpg" class="mw-file-description" title="Closeup of installer bit. The fishing hole is visible in the flute in the center of the picture."><img alt="Closeup of installer bit. The fishing hole is visible in the flute in the center of the picture." src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Installer_bit_closeup_2.jpg/240px-Installer_bit_closeup_2.jpg" decoding="async" width="240" height="180" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Installer_bit_closeup_2.jpg/360px-Installer_bit_closeup_2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Installer_bit_closeup_2.jpg/480px-Installer_bit_closeup_2.jpg 2x" data-file-width="1984" data-file-height="1488" /></a></span></div> <div class="gallerytext">Closeup of installer bit. The fishing hole is visible in the flute in the center of the picture.</div> </li> </ul> <div class="mw-heading mw-heading4"><h4 id="Flexible_shaft_bit">Flexible shaft bit</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=44" title="Edit section: Flexible shaft bit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Another, different, bit also called an installer bit has a very long flexible shaft, typically up to 72 inches (1.8 m) long, with a small twist bit at the end. The shaft is made of <a href="/wiki/Martensite" title="Martensite">spring steel</a> instead of hardened <a href="/wiki/Steel" title="Steel">steel</a>, so it can be flexed while drilling without breaking. This allows the bit to be curved inside walls, for example to drill through <a href="/wiki/Wall_stud" title="Wall stud">studs</a> from a <a href="/wiki/Light_switch" title="Light switch">light switch</a> box without needing to remove any material from the wall. These bits usually come with a set of special tools to aim and flex the bit to reach the desired location and angle, although the problem of seeing where the operator is drilling still remains. </p><p>This flexible installer bit is used in the US, but does not appear to be routinely available in Europe. </p> <div class="mw-heading mw-heading2"><h2 id="Drill_bit_shank">Drill bit shank</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=45" title="Edit section: Drill bit shank"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Drill_bit_shank" title="Drill bit shank">Drill bit shank</a></div> <p>Different shapes of shank are used. Some are simply the most appropriate for the chuck used; in other cases particular combinations of shank and chuck give performance advantages, such as allowing higher torque, greater centering accuracy, or efficient hammering action. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=46" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Drill_and_tap_size_chart" class="mw-redirect" title="Drill and tap size chart">Drill and tap size chart</a></li> <li><a href="/wiki/Drill_bit_shank" title="Drill bit shank">Drill bit shank</a></li> <li><a href="/wiki/Drill_bit_sizes" title="Drill bit sizes">Drill bit sizes</a></li> <li><a href="/wiki/Drill_rod" class="mw-redirect" title="Drill rod">Drill rod</a></li> <li><a href="/wiki/Endmill" class="mw-redirect" title="Endmill">Endmill</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=47" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Citations">Citations</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=48" title="Edit section: Citations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width reflist-columns-2"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=rI-15fovYEY">"Practical demonstration of square-hole bit, YouTube video"</a>. Youtube.com. 18 October 2011. <a rel="nofollow" class="external text" href="https://ghostarchive.org/varchive/youtube/20211212/rI-15fovYEY">Archived</a> from the original on 2021-12-12<span class="reference-accessdate">. Retrieved <span class="nowrap">2014-05-10</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Practical+demonstration+of+square-hole+bit%2C+YouTube+video&rft.pub=Youtube.com&rft.date=2011-10-18&rft_id=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DrI-15fovYEY&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADrill+bit" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFToddAllenAlting1994" class="citation cs2">Todd, Robert H.; Allen, Dell K.; Alting, Leo (1994), <a rel="nofollow" class="external text" href="https://books.google.com/books?id=6x1smAf_PAcC"><i>Manufacturing Processes Reference Guide</i></a>, Industrial Press Inc., pp. 43–48, <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-8311-3049-0" title="Special:BookSources/0-8311-3049-0"><bdi>0-8311-3049-0</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Manufacturing+Processes+Reference+Guide&rft.pages=43-48&rft.pub=Industrial+Press+Inc.&rft.date=1994&rft.isbn=0-8311-3049-0&rft.aulast=Todd&rft.aufirst=Robert+H.&rft.au=Allen%2C+Dell+K.&rft.au=Alting%2C+Leo&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3D6x1smAf_PAcC&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADrill+bit" class="Z3988"></span></span> </li> <li id="cite_note-doi.org-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-doi.org_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-doi.org_3-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="//doi.org/10.1115/1.4040916" class="extiw" title="doi:10.1115/1.4040916">Swan et al (September 7, 2018). "Tool Wear of Advanced Coated Tools in Drilling of CFRP." ASME. J. Manuf. Sci. Eng. November 2018; 140(11): 111018.</a></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><a href="//doi.org/10.1115/MSEC2019-2843" class="extiw" title="doi:10.1115/MSEC2019-2843">Nguyen, Dinh et al "Tool Wear of Superhard Ceramic Coated Tools in Drilling of CFRP/Ti stacks." Proceedings of the ASME 2019 14th International Manufacturing Science and Engineering Conference. Volume 2: Processes; Materials. Erie, Pennsylvania, USA. June 10–14, 2019. V002T03A089. ASME.</a></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><a href="//doi.org/10.1115/MSEC2019-2843" class="extiw" title="doi:10.1115/MSEC2019-2843">Nguyen, Dinh et al "Tool Wear of Superhard Ceramic Coated Tools in Drilling of CFRP/Ti Stacks." Proceedings of the ASME 2019 14th International Manufacturing Science and Engineering Conference. Volume 2: Processes; Materials. Erie, Pennsylvania, USA. June 10–14, 2019. V002T03A089. ASME.</a></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJudge1947" class="citation book cs1">Judge, Arthur W (1947). <i>Engineering Workshop Practice</i> (New and Revised ed.). The Caxton Publishing Company Ltd. pp. Vol i 136.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Engineering+Workshop+Practice&rft.pages=Vol+i+136&rft.edition=New+and+Revised&rft.pub=The+Caxton+Publishing+Company+Ltd&rft.date=1947&rft.aulast=Judge&rft.aufirst=Arthur+W&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADrill+bit" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation cs2"><a rel="nofollow" class="external text" href="https://books.google.com/books?id=hZzmAAAAMAAJ&pg=PA68"><i>Modern machinery</i></a>, vol. 5, Modern Machining Publishing Company, 1899, p. 68.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Modern+machinery&rft.pages=68&rft.pub=Modern+Machining+Publishing+Company&rft.date=1899&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DhZzmAAAAMAAJ%26pg%3DPA68&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADrill+bit" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.datamp.org//patents/displayPatent.php?pn=38119&id=18675">"US Patent: 38,119 - Twist Drill Bit"</a>. <i>www.datamp.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.datamp.org&rft.atitle=US+Patent%3A+38%2C119+-+Twist+Drill+Bit&rft_id=https%3A%2F%2Fwww.datamp.org%2F%2Fpatents%2FdisplayPatent.php%3Fpn%3D38119%26id%3D18675&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADrill+bit" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><a href="#CITEREFObergJonesHortonRyffel2000">Oberg et al. 2000</a>, pp. 829, 846</span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><a href="#CITEREFObergJonesHortonRyffel2000">Oberg et al. 2000</a>, p. 846</span> </li> <li id="cite_note-gillespie-11"><span class="mw-cite-backlink">^ <a href="#cite_ref-gillespie_11-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-gillespie_11-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-gillespie_11-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGillespie2008" class="citation cs2">Gillespie, Laroux (2008), <a rel="nofollow" class="external text" href="https://books.google.com/books?id=esWtCQuLWtIC&pg=PA78"><i>Countersinking Handbook</i></a>, Industrial Press Inc., pp. 78–79, <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-8311-3318-4" title="Special:BookSources/978-0-8311-3318-4"><bdi>978-0-8311-3318-4</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Countersinking+Handbook&rft.pages=78-79&rft.pub=Industrial+Press+Inc.&rft.date=2008&rft.isbn=978-0-8311-3318-4&rft.aulast=Gillespie&rft.aufirst=Laroux&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DesWtCQuLWtIC%26pg%3DPA78&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADrill+bit" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><span><a rel="nofollow" class="external text" href="https://patents.google.com/patent/US3758222">U.S. patent 3,758,222</a></span></span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text">McMaster-Carr, p. 2438, 116th edition.</span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1041539562">.mw-parser-output .citation{word-wrap:break-word}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}</style><span class="citation patent" id="CITEREFBenjamin_Forstner1886"><a rel="nofollow" class="external text" href="https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=CA23548">CA patent 23548</a>, Benjamin Forstner, "Auger", published 1886-03-06</span><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Apatent&rft.number=23548&rft.cc=CA&rft.title=Auger&rft.inventor=Benjamin+Forstner&rft.pubdate=1886-03-06"><span style="display: none;"> </span></span></span> </li> </ol></div> <div class="mw-heading mw-heading3"><h3 id="Cited_references">Cited references</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Drill_bit&action=edit&section=49" title="Edit section: Cited references"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFObergJonesHortonRyffel2000" class="citation cs2">Oberg, Erik; Jones, Franklin D.; Horton, Holbrook L.; Ryffel, Henry H. (2000), <i><a href="/wiki/Machinery%27s_Handbook" title="Machinery's Handbook">Machinery's Handbook</a></i> (26th ed.), New York: Industrial Press Inc., <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0-8311-2635-3" title="Special:BookSources/0-8311-2635-3"><bdi>0-8311-2635-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Machinery%27s+Handbook&rft.place=New+York&rft.edition=26th&rft.pub=Industrial+Press+Inc.&rft.date=2000&rft.isbn=0-8311-2635-3&rft.aulast=Oberg&rft.aufirst=Erik&rft.au=Jones%2C+Franklin+D.&rft.au=Horton%2C+Holbrook+L.&rft.au=Ryffel%2C+Henry+H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADrill+bit" class="Z3988"></span></li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a 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href="/wiki/Category:Machining" title="Category:Machining">Machining</a> and computing</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Category:Computer-aided_engineering" title="Category:Computer-aided engineering">Computer-aided<br />engineering</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/2.5D_(machining)" title="2.5D (machining)">2.5D</a></li> <li><a href="/wiki/Computer-aided_design" title="Computer-aided design">CAD</a></li> <li><a href="/wiki/Computer-aided_manufacturing" title="Computer-aided manufacturing">CAM</a></li> <li><a href="/wiki/G-code" title="G-code">G-code</a></li> <li><a href="/wiki/Numerical_control" title="Numerical control">Numerical control (NC and CNC)</a></li> <li><a href="/wiki/Stewart_platform" title="Stewart platform">Stewart platform</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Category:Hole_making" title="Category:Hole making">Drilling</a> and<br /><a href="/wiki/Category:Threading_(manufacturing)" title="Category:Threading (manufacturing)">threading</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Die_head" title="Die head">Die head</a></li> <li><a href="/wiki/Drill" title="Drill">Drill</a></li> <li><a class="mw-selflink selflink">Drill bit</a></li> <li><a href="/wiki/Drill_bit_shank" title="Drill bit shank">Drill bit shank</a></li> <li><a href="/wiki/Drill_bit_sizes" title="Drill bit sizes">Drill bit sizes</a></li> <li><a href="/wiki/Drilling" title="Drilling">Drilling</a></li> <li><a href="/wiki/List_of_drill_and_tap_sizes" title="List of drill and tap sizes">List of drill and tap sizes</a></li> <li><a href="/wiki/Tap_and_die" title="Tap and die">Tap and die</a></li> <li><a href="/wiki/Tap_wrench" title="Tap wrench">Tap wrench</a></li> <li><a href="/wiki/Threading_(manufacturing)" title="Threading (manufacturing)">Threading</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Category:Grinding_and_lapping" title="Category:Grinding and lapping">Grinding and<br />lapping</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abrasive" title="Abrasive">Abrasive</a></li> <li><a href="/wiki/Abrasive_machining" title="Abrasive machining">Abrasive machining</a></li> <li><a href="/wiki/Angle_grinder" title="Angle grinder">Angle grinder</a></li> <li><a href="/wiki/Bench_grinder" title="Bench grinder">Bench grinder</a></li> <li><a href="/wiki/Coated_abrasive" class="mw-redirect" title="Coated abrasive">Coated abrasive</a></li> <li><a href="/wiki/Cylindrical_grinder" title="Cylindrical grinder">Cylindrical grinder</a></li> <li><a href="/wiki/Sharpening_stone#Diamond_plate" title="Sharpening stone">Diamond plate</a></li> <li><a href="/wiki/Flick_grinder" class="mw-redirect" title="Flick grinder">Flick grinder</a></li> <li><a href="/wiki/Grinding_(abrasive_cutting)" title="Grinding (abrasive cutting)">Grinding</a></li> <li><a href="/wiki/Grinding_dresser" title="Grinding dresser">Grinding dresser</a></li> <li><a href="/wiki/Grinding_machine" title="Grinding machine">Grinding machine</a></li> <li><a href="/wiki/Grinding_wheel" title="Grinding wheel">Grinding wheel</a></li> <li><a href="/wiki/Jig_grinder" title="Jig grinder">Jig grinder</a></li> <li><a href="/wiki/Lapping" title="Lapping">Lapping</a></li> <li><a href="/wiki/Sandpaper" title="Sandpaper">Sanding</a></li> <li><a href="/wiki/Sharpening_stone" title="Sharpening stone">Sharpening stone</a></li> <li><a href="/wiki/Spark_testing" title="Spark testing">Spark testing</a></li> <li><a href="/wiki/Surface_grinding" title="Surface grinding">Surface grinder</a></li> <li><a href="/wiki/Tool_and_cutter_grinder" title="Tool and cutter grinder">Tool and cutter grinder</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Category:Machining" title="Category:Machining">Machining</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Boring_(manufacturing)" title="Boring (manufacturing)">Boring</a></li> <li><a href="/wiki/Broaching_(metalworking)" title="Broaching (metalworking)">Broaching</a></li> <li><a href="/wiki/Electrical_discharge_machining" title="Electrical discharge machining">Electrical discharge machining</a></li> <li><a href="/wiki/Electrochemical_machining" title="Electrochemical machining">Electrochemical machining</a></li> <li><a href="/wiki/Electron-beam_machining" title="Electron-beam machining">Electron-beam machining</a></li> <li><a href="/wiki/End_mill" title="End mill">End mill</a></li> <li><a href="/wiki/Engraving" title="Engraving">Engraving</a></li> <li><a href="/wiki/Facing_(machining)" title="Facing (machining)">Facing</a></li> <li><a href="/wiki/Hobbing" title="Hobbing">Hobbing</a></li> <li><a href="/wiki/Jig_borer" title="Jig borer">Jig borer</a></li> <li><a href="/wiki/Machine_tool" title="Machine tool">Machine tool</a></li> <li><a href="/wiki/Machining" title="Machining">Machining</a></li> <li><a href="/wiki/Metal_lathe" title="Metal lathe">Metal lathe</a></li> <li><a href="/wiki/Milling_(machining)" title="Milling (machining)">Milling</a></li> <li><a href="/wiki/Milling_cutter" title="Milling cutter">Milling cutter</a></li> <li><a href="/wiki/Pantograph" title="Pantograph">Pantograph</a></li> <li><a href="/wiki/Photochemical_machining" title="Photochemical machining">Photochemical machining</a></li> <li><a href="/wiki/Planer_(metalworking)" title="Planer (metalworking)">Planer</a></li> <li><a href="/wiki/Reamer" title="Reamer">Reamer</a></li> <li><a href="/wiki/Rotary_transfer_machine" title="Rotary transfer machine">Rotary transfer machine</a></li> <li><a href="/wiki/Shaper" title="Shaper">Shaper</a></li> <li><a href="/wiki/Skiving_(metalworking)" title="Skiving (metalworking)">Skiving</a></li> <li><a href="/wiki/Turning" title="Turning">Turning</a></li> <li><a href="/wiki/Ultrasonic_machining" title="Ultrasonic machining">Ultrasonic machining</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Category:Machine_tools" title="Category:Machine tools">Machine tools</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Angle_plate" title="Angle plate">Angle plate</a></li> <li><a href="/wiki/Chuck_(engineering)" title="Chuck (engineering)">Chuck</a></li> <li><a href="/wiki/Collet" title="Collet">Collet</a></li> <li><a href="/wiki/Fixture_(tool)" title="Fixture (tool)">Fixture</a></li> <li><a href="/wiki/Indexing_head" title="Indexing head">Indexing head</a></li> <li><a href="/wiki/Jig_(tool)" title="Jig (tool)">Jig</a></li> <li><a href="/wiki/Lathe_center" title="Lathe center">Lathe center</a></li> <li><a href="/wiki/Machine_taper" title="Machine taper">Machine taper</a></li> <li><a href="/wiki/Magnetic_switchable_device" title="Magnetic switchable device">Magnetic switchable device</a></li> <li><a href="/wiki/Mandrel" title="Mandrel">Mandrel</a></li> <li><a href="/wiki/Rotary_table" title="Rotary table">Rotary table</a></li> <li><a href="/wiki/Wiggler_(tool)" title="Wiggler (tool)">Wiggler</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Terminology</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Cutting_fluid" title="Cutting fluid">Cutting fluid</a></li> <li><a href="/wiki/Machining_vibrations" title="Machining vibrations">Machining vibrations</a></li> <li><a href="/wiki/Speeds_and_feeds" title="Speeds and feeds">Speeds and feeds</a></li> <li><a href="/wiki/Swarf" title="Swarf">Swarf</a></li> <li><a href="/wiki/Engineering_tolerance" title="Engineering tolerance">Tolerance</a></li> <li><a href="/wiki/Tool_and_die_maker" title="Tool and die maker">Tool and die making</a></li> <li><a href="/wiki/Tramp_oil" class="mw-redirect" title="Tramp oil">Tramp oil</a></li> <li><a href="/wiki/Workpiece" title="Workpiece">Workpiece</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><a href="/wiki/Casting" title="Casting">Casting</a></li> <li><a href="/wiki/Metal_fabrication" title="Metal fabrication">Fabrication</a></li> <li><a href="/wiki/Forming_processes" title="Forming processes">Forming</a></li> <li><a href="/wiki/Jewellery" title="Jewellery">Jewellery</a></li> <li><a href="/wiki/Machining" title="Machining">Machining</a></li> <li><a href="/wiki/Metallurgy" title="Metallurgy">Metallurgy</a></li> <li><a href="/wiki/Metalsmith" title="Metalsmith">Smithing</a></li> <li><a href="/wiki/Outline_of_metalworking" title="Outline of metalworking">Tools and terminology</a></li> <li><a href="/wiki/Welding" title="Welding">Welding</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"></div><div role="navigation" class="navbox" aria-labelledby="Cutting_and_abrasive_tools" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Cutting_and_abrasive_tools" title="Template:Cutting and abrasive tools"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Cutting_and_abrasive_tools" title="Template talk:Cutting and abrasive tools"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Cutting_and_abrasive_tools" title="Special:EditPage/Template:Cutting and abrasive tools"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Cutting_and_abrasive_tools" style="font-size:114%;margin:0 4em"><a href="/wiki/Cutting" title="Cutting">Cutting</a> and <a href="/wiki/Abrasive" title="Abrasive">abrasive</a> tools</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Adze" title="Adze">Adze</a></li> <li><a href="/wiki/Axe" title="Axe">Axe</a></li> <li><a href="/wiki/Blade" title="Blade">Blade</a></li> <li><a href="/wiki/Bolt_cutter" title="Bolt cutter">Bolt cutter</a></li> <li><a href="/wiki/Broaching_(metalworking)" title="Broaching (metalworking)">Broach</a></li> <li><a href="/wiki/Burnisher" title="Burnisher">Burnisher</a></li> <li><a href="/wiki/Ceramic_tile_cutter" title="Ceramic tile cutter">Ceramic tile cutter</a></li> <li><a href="/wiki/Chisel" title="Chisel">Chisel</a></li> <li><a href="/wiki/Countersink" title="Countersink">Countersink</a></li> <li><a href="/wiki/Cutting_tool_(machining)" title="Cutting tool (machining)">Cutting tool</a></li> <li><a href="/wiki/Diagonal_pliers" title="Diagonal pliers">Diagonal pliers</a></li> <li><a href="/wiki/Diamond_blade" title="Diamond blade">Diamond blade</a></li> <li><a href="/wiki/Diamond_tool" title="Diamond tool">Diamond tool</a></li> <li><a href="/wiki/Disc_cutter" title="Disc cutter">Disc cutter</a></li> <li><a href="/wiki/Drawknife" title="Drawknife">Drawknife</a></li> <li><a class="mw-selflink selflink">Drill bit</a></li> <li><a href="/wiki/Emery_cloth" class="mw-redirect" title="Emery cloth">Emery cloth</a></li> <li><a href="/wiki/File_(tool)" title="File (tool)">File</a></li> <li><a href="/wiki/Froe" title="Froe">Froe</a></li> <li><a href="/wiki/Glass_cutter" title="Glass cutter">Glass cutter</a></li> <li><a href="/wiki/Grater" title="Grater">Grater</a></li> <li><a href="/wiki/Grinding_wheel" title="Grinding wheel">Grinding wheel</a></li> <li><a href="/wiki/Honing_steel" title="Honing steel">Honing steel</a></li> <li><a href="/wiki/Knife" title="Knife">Knife</a></li> <li><a href="/wiki/Laser_cutting" title="Laser cutting">Laser</a></li> <li><a href="/wiki/Lawn_mower" title="Lawn mower">Lawn mower</a></li> <li><a href="/wiki/Machete" title="Machete">Machete</a></li> <li><a href="/wiki/Meat_slicer" title="Meat slicer">Meat slicer</a></li> <li><a href="/wiki/Mezzaluna" title="Mezzaluna">Mezzaluna</a></li> <li><a href="/wiki/Milling_cutter" title="Milling cutter">Milling cutter</a></li> <li><a href="/wiki/Nail_clipper" title="Nail clipper">Nail clipper</a></li> <li><a href="/wiki/Nibbler" title="Nibbler">Nibbler</a></li> <li><a href="/wiki/Oxy-fuel_welding_and_cutting" title="Oxy-fuel welding and cutting">Oxy-fuel cutting torch</a></li> <li><a href="/wiki/Pencil_sharpener" title="Pencil sharpener">Pencil sharpener</a></li> <li><a href="/wiki/Pipecutter" title="Pipecutter">Pipecutter</a></li> <li><a href="/wiki/Pizza_cutter" title="Pizza cutter">Pizza cutter</a></li> <li><a href="/wiki/Plasma_cutting" title="Plasma cutting">Plasma cutter</a></li> <li><a href="/wiki/Plane_(tool)" title="Plane (tool)">Plane</a></li> <li><a href="/wiki/Pocket_knife" class="mw-redirect" title="Pocket knife">Pocket knife</a></li> <li><a href="/wiki/Putty_knife" title="Putty knife">Putty knife</a></li> <li><a href="/wiki/Rasp" title="Rasp">Rasp</a></li> <li><a href="/wiki/Razor" title="Razor">Razor</a></li> <li><a href="/wiki/Razor_strop" title="Razor strop">Razor strop</a></li> <li><a href="/wiki/Reamer" title="Reamer">Reamer</a></li> <li><a href="/wiki/Sandpaper" title="Sandpaper">Sandpaper</a></li> <li><a href="/wiki/Saw" title="Saw">Saw</a> <ul><li><a href="/wiki/Abrasive_saw" title="Abrasive saw">Abrasive saw</a></li> <li><a href="/wiki/Bandsaw" title="Bandsaw">Bandsaw</a></li> <li><a href="/wiki/Chainsaw" title="Chainsaw">Chainsaw</a></li> <li><a href="/wiki/Circular_saw" title="Circular saw">Circular saw</a></li> <li><a href="/wiki/Concrete_saw" title="Concrete saw">Concrete saw</a></li> <li><a href="/wiki/Coping_saw" title="Coping saw">Coping saw</a></li> <li><a href="/wiki/Fretsaw" title="Fretsaw">Fretsaw</a></li> <li><a href="/wiki/Hacksaw" title="Hacksaw">Hacksaw</a></li> <li><a href="/wiki/Hand_saw" title="Hand saw">Hand saw</a></li> <li><a href="/wiki/Hole_saw" title="Hole saw">Hole saw</a></li> <li><a href="/wiki/Miter_saw" title="Miter saw">Miter saw</a></li> <li><a href="/wiki/Wire_saw" title="Wire saw">Wire saw</a></li></ul></li> <li><a href="/wiki/Scalpel" title="Scalpel">Scalpel</a></li> <li><a href="/wiki/Scissors" title="Scissors">Scissors</a></li> <li>Scraper <ul><li><a href="/wiki/Card_scraper" title="Card scraper">Card</a></li> <li><a href="/wiki/Hand_scraper" title="Hand scraper">Hand</a></li> <li><a href="/wiki/Paint_scraper" class="mw-redirect" title="Paint scraper">Paint</a></li></ul></li> <li><a href="/wiki/Sharpening_jig" title="Sharpening jig">Sharpening jig</a></li> <li><a href="/wiki/Sharpening_stone" title="Sharpening stone">Sharpening stone</a></li> <li><a href="/wiki/Snips" title="Snips">Snips</a></li> <li><a href="/wiki/Steel_wool" title="Steel wool">Steel wool</a></li> <li><a href="/wiki/Surform" title="Surform">Surform</a></li> <li><a href="/wiki/Switchblade" title="Switchblade">Switchblade</a></li> <li><a href="/wiki/Tool_bit" title="Tool bit">Tool bit</a></li> <li><a href="/wiki/Utility_knife" title="Utility knife">Utility knife</a></li> <li><a href="/wiki/Water_jet_cutter" title="Water jet cutter">Water jet cutter</a></li> <li><a href="/wiki/Wire_brush" title="Wire brush">Wire brush</a></li> <li><a href="/wiki/Wire_stripper" title="Wire stripper">Wire stripper</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><div class="hlist"> <dl><dt><a href="/wiki/Template:Types_of_tools" title="Template:Types of tools">Types of tools</a></dt> <dd><a href="/wiki/Template:Cleaning_tools" title="Template:Cleaning tools">Cleaning</a></dd> <dd><a href="/wiki/Template:Cutting_and_abrasive_tools" title="Template:Cutting and abrasive tools">Cutting and abrasive</a></dd> <dd><a href="/wiki/Template:Forestry_tools" title="Template:Forestry tools">Forestry</a></dd> <dd><a 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