{"product_id":"walter-6388430-turning-insert-cnma643-rk5-wkk20s-carbide","title":"Walter 6388430 Turning Insert CNMA643-RK5 WKK20S Carbide","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe WALTER 6388430 is a solid carbide turning insert in the CNMA643-RK5 WKK20S configuration, engineered for high-performance machining of cast iron and steel. It carries a CVD-applied multilayer coating of TiCN, Al2O3, and TiCN, designated under WALTERs proprietary grade WKK20S and aligned with the Tiger-tec Silver series. The insert features an 80-degree diamond shape with a negative rake angle and a chamfered and honed cutting edge, delivering controlled chip formation and edge stability under demanding cutting conditions. With four available cutting edges and compatibility with both clamp and pin holding methods, it provides extended tool life and consistent performance in turning, facing, and boring operations.\u003c\/p\u003e\u003cp\u003eThis insert is suited for roughing and semi-finishing applications on cast iron (ISO material code K) and steel (ISO material code P) workpieces. It fits standard CNMA toolholders used in CNC turning centers and manual lathes across production machining environments. The RK5 chip breaker geometry is designed to manage chip evacuation at moderate-to-heavy depths of cut up to 0.315 inches (8.00 mm). Licensed machinists and CNC operators in job shop and production settings will find this insert appropriate for general turning, facing, and boring tasks requiring stable edge geometry and predictable wear behavior.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eCVD multilayer coating: TiCN, Al2O3, TiCN under proprietary grade WKK20S for wear resistance on cast iron and steel\u003c\/li\u003e\n\u003cli\u003e80-degree diamond insert shape with negative rake and chamfered and honed cutting edge for stable cuts\u003c\/li\u003e\n\u003cli\u003eFour cutting edges per insert maximize utilization and reduce per-edge tooling cost\u003c\/li\u003e\n\u003cli\u003eRK5 chip breaker geometry supports turning, facing, and boring with maximum depth of cut of 0.315 inches\u003c\/li\u003e\n\u003cli\u003eCompatible with clamp and pin holding methods for secure seating in standard CNMA toolholders\u003c\/li\u003e\n\u003cli\u003eMeets ANSI and ISO standards; ISO code CNMA190612-RK5 WKK20S\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned for use in standard CNMA-style toolholders that accept a 3\/4-inch inscribed circle insert. Suitable for turning, facing, and boring operations on cast iron (ISO K) and steel (ISO P) workpieces. ISO equivalent designation is CNMA190612-RK5 WKK20S.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eInstallation should be performed by a qualified machinist following the toolholder manufacturers seating and clamping procedure. Ensure the machine spindle is fully stopped and all motion is locked out before indexing or replacing inserts. Confirm the insert pocket is clean and free of chips before seating to prevent uneven clamping and premature edge failure. Verify clamping torque and pin engagement per the toolholder manufacturers specification.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eInsert Style\u003c\/strong\u003e: CNMA\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndustry Standard Number\u003c\/strong\u003e: CNMA643-RK5 WKK20S\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eISO Code\u003c\/strong\u003e: CNMA190612-RK5 WKK20S\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInsert Shape\u003c\/strong\u003e: Diamond 80\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIncluded Angle\u003c\/strong\u003e: 80 degrees\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\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\u003eSeries\u003c\/strong\u003e: Tiger-tec Silver, CNMA-RK5\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChip Breaker\u003c\/strong\u003e: RK5\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: 0 degrees\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRelief Angle\u003c\/strong\u003e: 0 degrees\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClearance Code\u003c\/strong\u003e: N\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTolerance Code\u003c\/strong\u003e: M\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\u003eWiper Edge\u003c\/strong\u003e: No\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNumber of Cutting Edges\u003c\/strong\u003e: 4\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInsert Holding Method\u003c\/strong\u003e: Clamp and Pin\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInscribed Circle\u003c\/strong\u003e: 3\/4 inch (0.7500 inches)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInsert Thickness\u003c\/strong\u003e: 1\/4 inch (0.2500 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\u003eCorner Radius\u003c\/strong\u003e: 3\/64 inch (0.0469 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\u003eInsert Size Code\u003c\/strong\u003e: 643\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\u003eStandards\u003c\/strong\u003e: ANSI, ISO\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUNSPSC Code\u003c\/strong\u003e: 23242105\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight\u003c\/strong\u003e: 4.59 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: WALTER\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 6388430\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"WALTER","offers":[{"title":"Default Title","offer_id":51986223497522,"sku":"6388430","price":637.67,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/6eaaf68a79e7d1b11e63dcf442c29f06.jpg?v=1789985996","url":"https:\/\/voomisupply.com\/products\/walter-6388430-turning-insert-cnma643-rk5-wkk20s-carbide","provider":"Voomi Supply","version":"1.0","type":"link"}