{"product_id":"sandvik-coromant-6138403-threading-toolholder-3-4-inch","title":"Sandvik Coromant 6138403 Threading Toolholder 3\/4 Inch","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe SANDVIK COROMANT 6138403 is an external, right-hand indexable threading toolholder designed for precision thread-turning operations on CNC lathes and turning centers. Part of the CoroThread 266 series, it accepts 266.RG to 16.. inserts secured by a screw-clamping method, ensuring repeatable positioning and rigid insert lockdown during cut. The steel shank measures 0.75 inches wide by 0.75 inches tall with an overall length of 4.5 inches, making it a compact but robust choice for threading passes on external workpiece diameters. Machinists and toolroom professionals handling production threading work will find this holder well-suited to both interrupted and continuous thread profiles.\u003c\/p\u003e\u003cp\u003eThis toolholder is intended for external threading applications on turning equipment where a right-hand cutting orientation is required. The CoroThread 266 series is engineered for consistent thread form accuracy across high-volume production runs as well as job-shop single-part work. It is compatible with standard CNC lathe turrets that accept 0.75 x 0.75 inch shank tooling. Coolant-through capability is not included on this holder, so external coolant delivery should be directed at the cutting zone as needed for the workpiece material.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eExternal, right-hand threading orientation for standard CNC lathe setups\u003c\/li\u003e\n\u003cli\u003eCoroThread 266 series toolholder style 266R\/LFA with screw-clamping insert retention\u003c\/li\u003e\n\u003cli\u003eAccepts 266.RG to 16.. indexable threading inserts\u003c\/li\u003e\n\u003cli\u003eSteel construction for rigidity and long-term dimensional stability\u003c\/li\u003e\n\u003cli\u003eCompact 4.5 inch overall length with 0.921 inch head length for close-clearance applications\u003c\/li\u003e\n\u003cli\u003eBack-of-bar to cutting edge distance of 0.77 inches for precise tool offset setup\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eCompatible with indexable inserts in the 266.RG to 16.. designation range within the CoroThread 266 series. Fits CNC lathe turrets and toolblocks that accept 0.75 x 0.75 inch square shank external threading toolholders.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eInstallation should be performed by a qualified machinist or toolroom technician. Power down and lock out the machine spindle before mounting or removing the toolholder from the turret. Ensure the turret pocket and shank seating surfaces are clean and free of chips before tightening clamp screws to the machine manufacturer's specified torque. Verify tool offset and cutting edge height against centerline before initiating a threading pass.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: CoroThread 266\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eToolholder Style\u003c\/strong\u003e: 266R\/LFA\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThread Type\u003c\/strong\u003e: External\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHand of Holder\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInsert Compatibility\u003c\/strong\u003e: 266.RG to 16..\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInsert Holding Method\u003c\/strong\u003e: Screw\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShank Width\u003c\/strong\u003e: 0.75 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShank Height\u003c\/strong\u003e: 0.75 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverall Length\u003c\/strong\u003e: 4.5 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHead Length\u003c\/strong\u003e: 0.921 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBack of Bar to Cutting Edge\u003c\/strong\u003e: 0.77 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eToolholder Material\u003c\/strong\u003e: Steel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoolant Through\u003c\/strong\u003e: No\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 0.71 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: SANDVIK COROMANT\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 6138403\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"SANDVIK COROMANT","offers":[{"title":"Default Title","offer_id":51745968128306,"sku":"6138403","price":330.03,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/89f71ff34c1c0b6255ceb1a8d66429ff.jpg?v=1788866140","url":"https:\/\/voomisupply.com\/products\/sandvik-coromant-6138403-threading-toolholder-3-4-inch","provider":"Voomi Supply","version":"1.0","type":"link"}