{"product_id":"osg-3142903-straight-flute-tap-4-40-unc-bottoming","title":"Osg 3142903 Straight Flute Tap 4-40 Unc Bottoming","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe OSG 3142903 is a straight flute tap designed for cutting internal threads in bottoming applications where full thread depth close to the base of a blind hole is required. Built from cobalt high-speed steel and finished with a nitride coating, the tap resists wear and handles elevated cutting temperatures better than standard HSS tooling. The 4-flute straight flute geometry provides rigidity and a clean thread form in materials such as plastics. It cuts a 4-40 UNC right-hand thread to a 2B class of fit, which is the standard tolerance for most general fastener applications. Licensed machinists, toolmakers, and maintenance technicians use this tap for precision threading in small-diameter work.\u003c\/p\u003e\u003cp\u003eThis tap is suited for threading 4-40 UNC holes in plastic workpieces in both production and repair environments. The bottoming chamfer  -  typically 1 to 2 thread leads  -  allows the tap to reach near the bottom of a blind hole, making it the correct choice when a plug or taper tap cannot produce a full thread length. It is commonly used with a tapping head, tap wrench, or CNC rigid tapping cycle where coolant-through tooling is not required.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eCobalt HSS construction for improved heat and wear resistance over standard HSS\u003c\/li\u003e\n\u003cli\u003eNitride coating reduces friction and extends tool life in abrasive materials\u003c\/li\u003e\n\u003cli\u003eBottoming chamfer enables full thread depth in blind holes\u003c\/li\u003e\n\u003cli\u003e4 straight flutes provide rigidity and clean thread form in plastics\u003c\/li\u003e\n\u003cli\u003e2B class of fit meets standard tolerance requirements for most UNC fastener applications\u003c\/li\u003e\n\u003cli\u003eRight-hand thread direction compatible with conventional tapping operations\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned for cutting 4-40 UNC internal threads in plastic materials; suitable for use with standard tap wrenches, tapping heads, and CNC tapping cycles that accept round-shank taps of the appropriate shank diameter.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eThis tap is installed and used by machinists and maintenance technicians performing threading operations. Always secure the workpiece and use a correctly sized and drilled tap drill hole before beginning the tapping operation. Apply appropriate cutting fluid for the material being tapped even when coolant-through tooling is not in use. Inspect the tap for wear or chipping before each use  -  a damaged tap can produce undersized or malformed threads.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 4-40 UNC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Standard\u003c\/strong\u003e: UNC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThreads per Inch\u003c\/strong\u003e: 40\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClass of Fit\u003c\/strong\u003e: 2B\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNumber of Flutes\u003c\/strong\u003e: 4\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChamfer Type\u003c\/strong\u003e: Bottoming\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Direction\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Cobalt HSS\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoating\u003c\/strong\u003e: Nitride\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial Application\u003c\/strong\u003e: Plastic\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverall Length\u003c\/strong\u003e: 1.874 inches (9\/16 inch nominal)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Length\u003c\/strong\u003e: 0.295 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShank Diameter\u003c\/strong\u003e: 0.141 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSquare Length\u003c\/strong\u003e: 0.1875 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSquare Size\u003c\/strong\u003e: 0.11 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNeck Length\u003c\/strong\u003e: 0.5596 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoolant Through\u003c\/strong\u003e: No\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOversize\u003c\/strong\u003e: No\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: 114\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.01 pounds\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: OSG\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 3142903\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"OSG","offers":[{"title":"Default Title","offer_id":51744229065010,"sku":"3142903","price":27.24,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/1387a1cbc85e69f037e155e448d18e22_6de34087-de8d-4611-9b6e-29b6654f1c68.jpg?v=1788855176","url":"https:\/\/voomisupply.com\/products\/osg-3142903-straight-flute-tap-4-40-unc-bottoming","provider":"Voomi Supply","version":"1.0","type":"link"}