{"product_id":"osg-1400128401-thread-forming-tap-1-4-28-unf-cobalt","title":"Osg 1400128401 Thread Forming Tap 1\/4-28 Unf Cobalt","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe OSG 1400128401 is a thread forming tap designed for cold-forming internal threads without cutting, producing stronger threads by work-hardening the material rather than removing chips. Built from cobalt high-speed steel with a steam oxide finish, this tap handles 1\/4-28 UNF right-hand threads in blind hole applications. The modified bottoming chamfer with 2 to 2.5 chamfered threads allows threading closer to the bottom of a blind hole than a standard plug tap. With an H4 thread limit and an overall length of 2.5 inches, it fits standard tap holders and machines used in precision threading operations. Machinists, tool and die makers, and maintenance technicians install this tap in CNC and manual tapping setups.\u003c\/p\u003e\n\u003cp\u003eThis tap is suited for threading blind holes in a range of ferrous and non-ferrous metals commonly encountered in production and repair environments. Rated for alloy steel, carbon steel, stainless steel, die steel, hardened steel, and aluminum, it covers a broad cross-section of workpiece materials found in aerospace, automotive, and general manufacturing. The HY-PRO NRT series is engineered for thread forming rather than thread cutting, meaning it is used exclusively where the base material has enough ductility to flow under the forming lobes. Tapping depth reaches 0.933 inches, making it practical for typical blind hole depths in the 1\/4-28 UNF size range.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e1\/4-28 UNF right-hand thread form, H4 thread limit for consistent fit\u003c\/li\u003e\n  \u003cli\u003eModified bottoming chamfer with 2 to 2.5 chamfered threads for threading close to blind hole bottoms\u003c\/li\u003e\n  \u003cli\u003eCobalt high-speed steel construction for added heat and wear resistance in tough materials\u003c\/li\u003e\n  \u003cli\u003eSteam oxide coating reduces friction and improves lubrication retention during tapping\u003c\/li\u003e\n  \u003cli\u003eNo coolant-through design; compatible with standard external flood or manual lubrication\u003c\/li\u003e\n  \u003cli\u003eThread forming process produces chip-free operation, eliminating chip-packing in blind holes\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned for blind hole threading in alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum workpieces requiring 1\/4-28 UNF internal threads. Material application codes P and N apply per the supplier specification.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eThread forming taps require a properly sized forming tap drill hole, which is larger than a standard cut tap drill size for the same thread — consult a forming tap drill chart for the correct hole diameter before starting. Always apply a suitable tapping fluid or cutting oil rated for the workpiece material; the steam oxide coating aids lubrication retention but does not replace lubricant. Use a calibrated torque-controlled tapping head or CNC rigid tapping cycle to avoid overloading the tap shank, especially near the bottom of a blind hole. Secure the workpiece fully before tapping and verify spindle alignment to prevent tap breakage.\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\u003eThread Direction\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Limit\u003c\/strong\u003e: H4\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eChamfer\u003c\/strong\u003e: Modified Bottoming\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eChamfered Threads\u003c\/strong\u003e: 2 to 2.5P\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eApplication\u003c\/strong\u003e: Blind Hole Threading\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Cobalt High-Speed Steel\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCoating\u003c\/strong\u003e: Steam Oxide\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial Application\u003c\/strong\u003e: Alloy Steel, Aluminum, Carbon Steel, Die Steel, Hardened Steel, Stainless Steel\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: 0.594 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTapping Depth\u003c\/strong\u003e: 0.933 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\u003eSquare Size\u003c\/strong\u003e: 0.191 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\u003eCoolant Through\u003c\/strong\u003e: No\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: HY-PRO NRT\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.035 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: 1400128401\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"OSG","offers":[{"title":"Default Title","offer_id":51755351540018,"sku":"1400128401","price":30.78,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/f9e0a7535aeb52c331c9ab34d6077839_c8afd917-970c-4661-895d-629ddf05d2f8.jpg?v=1788954032","url":"https:\/\/voomisupply.com\/products\/osg-1400128401-thread-forming-tap-1-4-28-unf-cobalt","provider":"Voomi Supply","version":"1.0","type":"link"}