{"product_id":"osg-2940401-spiral-flute-tap-1-4-28-unf-modified-bottoming","title":"Osg 2940401 Spiral Flute Tap 1\/4-28 Unf Modified Bottoming","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe OSG 2940401 is a spiral flute tap designed for cutting internal right-hand threads to the 1\/4-28 UNF standard. Built from vanadium high-speed steel with a steam oxide coating, it delivers hardness retention and reduced friction during tapping operations. The modified bottoming chamfer allows threading close to the bottom of blind holes, making it well-suited for tight-tolerance work. With a 45-degree helix angle and 3 right-hand flutes, the tool efficiently evacuates chips upward out of the hole during the cut. Licensed machinists, tool-and-die makers, and maintenance technicians are the primary users.\u003c\/p\u003e\n\u003cp\u003eThis tap is intended for use in blind and through-hole applications requiring UNF fine-thread profiles. Its material compatibility spans a wide range of metals, including alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel. The H5 thread limit designation indicates a close-tolerance fit suitable for precision assemblies. It fits standard tap holders and is appropriate for both hand tapping and machine tapping setups where controlled feed is maintained.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003eModified bottoming chamfer for threading close to the bottom of blind holes\u003c\/li\u003e\n  \u003cli\u003e45-degree helix angle with 3 spiral flutes for upward chip evacuation\u003c\/li\u003e\n  \u003cli\u003eVanadium high-speed steel construction for hardness and wear resistance\u003c\/li\u003e\n  \u003cli\u003eSteam oxide coating reduces friction and provides mild corrosion resistance\u003c\/li\u003e\n  \u003cli\u003eH5 thread limit for close-tolerance UNF thread production\u003c\/li\u003e\n  \u003cli\u003eCompatible with a broad range of ferrous materials including hardened steel\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned for cutting 1\/4-28 UNF right-hand internal threads in alloy steel, carbon steel, cast iron, stainless steel, die steel, and hardened steel workpieces. Part of OSG Series 290.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eThis tap is installed by machinists or maintenance technicians using a standard tap wrench or machine tap holder. Ensure the workpiece is securely clamped and the pilot hole diameter is correctly sized for a 1\/4-28 UNF thread before starting. Apply appropriate cutting fluid for the workpiece material to extend tool life and improve thread quality. Do not force the tap if resistance increases unexpectedly, as breakage in blind holes can be difficult to recover from.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 1\/4-28 UNF\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Standard\u003c\/strong\u003e: UNF\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThreads per Inch\u003c\/strong\u003e: 28\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eChamfer\u003c\/strong\u003e: Modified Bottoming\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNumber of Flutes\u003c\/strong\u003e: 3\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlute Style\u003c\/strong\u003e: Spiral\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlute Direction\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHelix Angle\u003c\/strong\u003e: 45 degrees\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Direction\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Limit\u003c\/strong\u003e: H5\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Vanadium 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\u003eOverall Length\u003c\/strong\u003e: 2.5 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Length\u003c\/strong\u003e: 0.397 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShank Diameter\u003c\/strong\u003e: 0.255 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNeck Length\u003c\/strong\u003e: 0.996 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSquare Length\u003c\/strong\u003e: 0.3125 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSquare Size\u003c\/strong\u003e: 0.191 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCoolant Through\u003c\/strong\u003e: No\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: 290\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.03 pounds\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eStandard Information\u003c\/h4\u003e\n\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: 2940401\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"OSG","offers":[{"title":"Default Title","offer_id":51730242830642,"sku":"2940401","price":47.43,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/90ad88c91f12f350d905d5a5d58ed092.jpg?v=1788713977","url":"https:\/\/voomisupply.com\/products\/osg-2940401-spiral-flute-tap-1-4-28-unf-modified-bottoming","provider":"Voomi Supply","version":"1.0","type":"link"}