{"product_id":"walter-6138535-turning-insert-cnmg643-mk5-wkk20s-carbide","title":"Walter 6138535 Turning Insert CNMG643-MK5 WKK20S Carbide","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe WALTER 6138535 is a CNMG-style indexable turning insert designed for high-productivity metal cutting on CNC lathes and turning centers. Manufactured from solid carbide in the WKK20S grade, this insert features a CVD-applied multilayer coating of TiCN, Al2O3, and TiCN that delivers thermal resistance and wear protection during demanding cuts. The 80-degree diamond insert shape and negative rake geometry provide strong cutting-edge support, while the MK5 chip breaker geometry promotes reliable chip control across a broad range of depths and feed rates. With 4 usable cutting edges per insert, it offers efficient cost-per-edge economics in production environments. It is installed by machinists and CNC setup technicians in machine shops and manufacturing facilities.\u003c\/p\u003e\n\u003cp\u003eThis insert is engineered primarily for cutting cast iron (ISO material code K) and steel (ISO material code P), covering material grades K20 and P10. It is suited for turning, facing, and boring operations. The insert accepts depths of cut up to 0.315 inches (8.00 mm), making it appropriate for both moderate roughing and semi-finishing passes. The chamfered and honed cutting edge style improves edge stability and reduces chipping risk on interrupted or variable-condition cuts. The Tiger-tec Silver series CVD coating is optimized for high cutting speeds in cast iron and general steel applications.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003eWKK20S solid carbide grade with CVD multilayer TiCN \/ Al2O3 \/ TiCN coating for thermal and abrasion resistance\u003c\/li\u003e\n  \u003cli\u003eCNMG insert style with 80-degree diamond shape and negative rake for strong edge support\u003c\/li\u003e\n  \u003cli\u003eMK5 chip breaker geometry for controlled chip formation across turning, facing, and boring\u003c\/li\u003e\n  \u003cli\u003e4 cutting edges per insert for reduced tooling cost per edge\u003c\/li\u003e\n  \u003cli\u003eChamfered and honed cutting edge style reduces chipping on variable workpiece conditions\u003c\/li\u003e\n  \u003cli\u003eCompatible with both clamp and pin insert-holding methods\u003c\/li\u003e\n  \u003cli\u003eConforms to ANSI and ISO standards; ISO code CNMG190612-MK5 WKK20S\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned as an OEM-style replacement and standard-fit insert for CNMG-style toolholders that accept a 3\/4-inch inscribed circle, 1\/4-inch thick, 80-degree diamond insert with a 0.312-inch hole diameter, using clamp or pin clamping. Conforms to ANSI and ISO CNMG insert standards (ISO code CNMG190612-MK5 WKK20S). Suitable for turning centers and CNC lathes equipped with compatible negative-rake CNMG toolholders.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eInstallation is performed by a qualified machinist or CNC tooling technician. Always index or replace inserts with the machine in a safe, powered-down or program-paused state and spindle stopped. Use the correct torque tool specified by the toolholder manufacturer when seating the clamp or pin to avoid seat damage or insert rocking. Inspect the insert pocket and seating surface for chips or debris before seating a new insert edge.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsert Style\u003c\/strong\u003e: CNMG\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: CNMG-MK5 (Tiger-tec Silver)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Grade\u003c\/strong\u003e: WKK20S\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial Grade\u003c\/strong\u003e: K20, P10\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsert Material\u003c\/strong\u003e: Solid Carbide\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCoating\u003c\/strong\u003e: TiCN \/ Al2O3 \/ TiCN (CVD)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsert Shape\u003c\/strong\u003e: Diamond 80 degrees\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eChip Breaker\u003c\/strong\u003e: MK5\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInscribed Circle\u003c\/strong\u003e: 3\/4 inches (0.7500 inches)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsert Thickness\u003c\/strong\u003e: 1\/4 inches (0.2500 inches)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCorner Radius\u003c\/strong\u003e: 3\/64 inches (0.0469 inches)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsert Length\u003c\/strong\u003e: 0.7616 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHole Diameter\u003c\/strong\u003e: 0.3120 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaximum Depth of Cut\u003c\/strong\u003e: 0.315 inches (8.00 mm)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNumber of Cutting Edges\u003c\/strong\u003e: 4\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRake\u003c\/strong\u003e: Negative\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRake Angle\u003c\/strong\u003e: 14 degrees\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRelief Angle\u003c\/strong\u003e: 0 degrees\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCutting Edge Style\u003c\/strong\u003e: Chamfered and Honed\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsert Hand\u003c\/strong\u003e: Neutral\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsert Holding Method\u003c\/strong\u003e: Clamp, Pin\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePrimary Workpiece Material\u003c\/strong\u003e: Cast Iron (ISO code K)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSecondary Workpiece Material\u003c\/strong\u003e: Steel (ISO code P)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMulti-Use Application\u003c\/strong\u003e: Turning, Facing, Boring\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWiper Edge\u003c\/strong\u003e: No\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFull Radius\u003c\/strong\u003e: No\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eISO Code\u003c\/strong\u003e: CNMG190612-MK5 WKK20S\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eStandards\u003c\/strong\u003e: ANSI, ISO\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePackage Weight\u003c\/strong\u003e: 4.59 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: WALTER\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 6138535\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"WALTER","offers":[{"title":"Default Title","offer_id":52122292748594,"sku":"6138535","price":640.02,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/769cb87e50c1a51c90efb520492232c6.jpg?v=1790085144","url":"https:\/\/voomisupply.com\/products\/walter-6138535-turning-insert-cnmg643-mk5-wkk20s-carbide","provider":"Voomi Supply","version":"1.0","type":"link"}