{"product_id":"osg-2103801-extension-tap-3-8-16-spiral-point-hss","title":"Osg 2103801 Extension Tap 3\/8-16 Spiral Point Hss","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe OSG 2103801 is a spiral point plug extension tap designed for right-hand threading in a range of metalworking applications. Built from high-speed steel with a steam oxide finish, it cuts 3\/8-16 UNC threads to a 3B class of fit with an H3 thread limit. The tap measures 4 inches overall length with a 1 inch thread length and features three flutes with a plug chamfer style. The reduced shank design enables reach into deeper or extended-clearance work areas where standard-length taps cannot access. Licensed machinists, tool and die makers, and maintenance technicians are the primary users of this tap in production and repair threading operations.\u003c\/p\u003e\u003cp\u003eThis extension tap is suited for threading through-holes in cast iron, aluminum castings, aluminum, and carbon steel workpieces. The spiral point geometry pushes chips forward ahead of the tap, making it well-suited for through-hole threading on CNC machines, drill presses, and manual tapping setups. The plug chamfer provides a gradual lead into the cut, making it appropriate for production runs and repair threading where thread quality and tool life consistency matter. Its extended reach is particularly useful in fixtures or assemblies where access is limited.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eSpiral point geometry pushes chips forward, optimizing through-hole threading performance\u003c\/li\u003e\n\u003cli\u003eHigh-speed steel construction provides durability across cast iron, aluminum, and carbon steel\u003c\/li\u003e\n\u003cli\u003eSteam oxide finish reduces friction and improves lubrication retention during the cut\u003c\/li\u003e\n\u003cli\u003eH3 thread limit and 3B class of fit ensure consistent, gauged thread production\u003c\/li\u003e\n\u003cli\u003eReduced shank extends reach for use in restricted or deep-clearance applications\u003c\/li\u003e\n\u003cli\u003eThree flutes with right-hand flute direction and plug chamfer for smooth thread entry\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned for threading 3\/8-16 UNC right-hand through-holes in cast iron, aluminum castings, aluminum, and carbon steel. Belongs to OSG Series 917.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eThis tap is installed and driven by a qualified machinist or maintenance technician using a standard tap wrench, tapping head, or CNC rigid-tapping spindle sized for the square drive. Ensure the workpiece is securely fixtured and the hole is drilled to the correct tap drill diameter for 3\/8-16 UNC threads before beginning. Apply appropriate cutting fluid for the workpiece material to extend tool life and improve thread finish. Follow shop safety procedures and applicable tooling standards when operating tapping equipment.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 3\/8-16\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Standard\u003c\/strong\u003e: UNC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Direction\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClass of Fit\u003c\/strong\u003e: 3B\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Limit\u003c\/strong\u003e: H3\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Length\u003c\/strong\u003e: 1 inch (0.787 inches decimal)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverall Length\u003c\/strong\u003e: 4 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNumber of Flutes\u003c\/strong\u003e: 3\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlute Direction\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTap Type\u003c\/strong\u003e: Spiral Point\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChamfer\u003c\/strong\u003e: Plug\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: High-Speed Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoating\/Finish\u003c\/strong\u003e: Steam Oxide\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHelix Angle\u003c\/strong\u003e: 0 degrees\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShank Diameter\u003c\/strong\u003e: 0.381 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSquare Size\u003c\/strong\u003e: 0.286 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSquare Length\u003c\/strong\u003e: 0.4375 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNeck Length\u003c\/strong\u003e: 0.413 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReduced Shank\u003c\/strong\u003e: Yes\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: 917\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial Application\u003c\/strong\u003e: Cast Iron, Aluminum Casting, Aluminum, Carbon Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Quantity\u003c\/strong\u003e: 1\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.124 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: 2103801\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"OSG","offers":[{"title":"Default Title","offer_id":51748659888434,"sku":"2103801","price":89.08,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/238ae33a23f7cab4872c2f0069345655.jpg?v=1788896318","url":"https:\/\/voomisupply.com\/products\/osg-2103801-extension-tap-3-8-16-spiral-point-hss","provider":"Voomi Supply","version":"1.0","type":"link"}