{"product_id":"osg-1804100-hand-sti-tap-4-40-unc-h2-3-flutes","title":"Osg 1804100 Hand Sti Tap 4-40 Unc H2 3 Flutes","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe OSG 1804100 is a hand STI tap designed for cutting STI (Screw Thread Insert) threads in a 4-40 UNC thread form. It features a bottoming chamfer for threading close to the bottom of blind holes, three flutes for chip evacuation, and an H2 thread limit for controlled thread tolerance. Constructed from high speed steel with a bright finish, this tap handles a range of workpiece materials including aluminum, carbon steel, cast iron, and hardened steel. The overall length is 1.875 inches with a thread length of 0.5625 inches. It is a hand tap intended for use with a tap wrench or handle rather than a machine spindle.\u003c\/p\u003e\u003cp\u003eThis tap is suited for creating threads to accept helical coil inserts in light-gauge fastener applications across maintenance, repair, and manufacturing environments. The 4-40 UNC designation makes it a common choice for small-component work in electronics assembly, instrument repair, and precision mechanical fabrication. The bottoming chamfer style allows threading to within one or two threads of a blind hole floor, making it the correct choice when thread engagement must extend deep into a shallow hole.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eBottoming chamfer allows threading close to the bottom of blind holes\u003c\/li\u003e\n\u003cli\u003eH2 thread limit provides consistent tolerance for STI thread inserts\u003c\/li\u003e\n\u003cli\u003eThree-flute design aids chip evacuation during hand tapping\u003c\/li\u003e\n\u003cli\u003eHigh speed steel construction suitable for aluminum, carbon steel, cast iron, and hardened steel\u003c\/li\u003e\n\u003cli\u003eBright finish  -  no coating buildup that could affect thread geometry\u003c\/li\u003e\n\u003cli\u003eCompact overall length of 1.875 inches with 0.5625 inch thread length for small workpiece access\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned for hand tapping applications requiring 4-40 UNC STI threads to accept screw thread inserts in aluminum, carbon steel, cast iron, and hardened steel workpieces.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eThis tap is intended for use by machinists, toolmakers, or maintenance technicians using a manual tap wrench. Always ensure the workpiece is secured and the starting hole is drilled and chamfered to the correct STI tap drill size before threading. Apply appropriate cutting fluid for the workpiece material to reduce tool wear and improve thread finish. Reverse the tap periodically during hand tapping to break chips and prevent tap breakage, especially in blind holes.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 4-40\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Standard\u003c\/strong\u003e: UNC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Limit\u003c\/strong\u003e: H2\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChamfer Type\u003c\/strong\u003e: Bottoming\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNumber of Flutes\u003c\/strong\u003e: 3\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Length\u003c\/strong\u003e: 0.5625 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverall Length\u003c\/strong\u003e: 1.875 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShank Diameter\u003c\/strong\u003e: 0.1410 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSquare Size\u003c\/strong\u003e: 0.1100 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: High Speed Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinish\u003c\/strong\u003e: Bright\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial Application\u003c\/strong\u003e: Aluminum, Carbon Steel, Cast Iron, Hardened Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: 126\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: 1804100\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"OSG","offers":[{"title":"Default Title","offer_id":51740325151026,"sku":"1804100","price":37.47,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/99eb4870d24efeb7ae3c00a994380953.jpg?v=1788824318","url":"https:\/\/voomisupply.com\/products\/osg-1804100-hand-sti-tap-4-40-unc-h2-3-flutes","provider":"Voomi Supply","version":"1.0","type":"link"}