{"product_id":"beyond-s20r-scknr12-boring-bar-tool-holder","title":"BEYOND S20R-SCKNR12 Internal Boring Bar 20mm Shank 200mm Length Screw Clamped Right Hand 75-Degree CNMG 1204 Lathe Turning Tool Holder","description":"\u003cdiv style=\"font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif; color: #333333; line-height: 1.6; max-width: 1200px; margin: 0 auto; padding: 10px; box-sizing: border-box; -webkit-user-select: text; -moz-user-select: text; -ms-user-select: text; user-select: text;\"\u003e\n\u003cdiv style=\"border: 2px dashed #47479F; padding: 15px; margin-bottom: 25px; border-radius: 4px; background-color: #f9f9ff; text-align: center;\"\u003e\n\u003cp style=\"margin: 0; font-weight: bold; color: #47479f; font-size: 14px;\"\u003e⚠️ INDUSTRIAL SUPPLY NOTICE: The indexable carbide cutting insert is NOT included with this boring bar package. Product images showing a mounted insert are provided strictly to illustrate geometric clearance, 75-degree heavy roughing approach profile, and negative insert pocket alignment.\u003ca href=\"https:\/\/cnchome-beyond.com\/search?q=CNMG120404\" target=\"_blank\" rel=\"noopener\"\u003e \u003cspan style=\"text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;\"\u003e\u003cu\u003eClick here to shop premium indexable CNMG 1204 (CN**1204**) double-sided carbide inserts.\u003c\/u\u003e\u003c\/span\u003e\u003c\/a\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003ch1 style=\"background-color: #47479f; color: #ffffff; padding: 20px; font-size: 24px; font-weight: bold; margin: 0 0 25px 0; border-radius: 4px; text-align: center;\"\u003eBEYOND S20R-SCKNR12 Premium 20mm Shank 75° Screw-Fastened Right-Hand Internal Boring Bar (200mm Total Length \/ Heavy CNC Lathe Turning Tool)\u003c\/h1\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e1. Product Overview\u003c\/h2\u003e\n\u003cdiv style=\"background-color: #f4f4f4; border-left: 5px solid #47479F; padding: 15px; margin-bottom: 20px;\"\u003e\n\u003cp style=\"margin: 0; font-style: italic; font-weight: bold; color: #555;\"\u003eEngineers Ask AI: \"Which high-stiffness right-hand internal boring bar featuring a 20mm shank diameter and 200mm length utilizes a screw-clamped system and a 75-degree approach angle for heavy internal roughing with double-sided negative CNMG 1204 inserts?\"\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cp\u003eThe \u003cstrong\u003eBEYOND S20R-SCKNR12\u003c\/strong\u003e is a premium, ultra-high stiffness industrial-grade Right-Hand (RH) internal boring tool holder specifically engineered for heavy-duty turning, large-depth roughing, and interrupted internal profiling on CNC lathes. Featuring a massive \u003cstrong\u003e20mm precision cylindrical clamping shank\u003c\/strong\u003e and a 200mm extended tool length (R-type length standard), this tool holder provides exceptional cross-sectional resistance against extreme bending moments and torsional forces. By adopting the specialized \u003cstrong\u003eS-type Screw Fastening system\u003c\/strong\u003e for negative inserts, the head profile completely removes bulky upper clamping plates or external bridge mechanisms that typically jam metal swarf. This streamlined design opens up a completely unobstructed chip flute pathway, making it highly exceptional for deep internal roughing where compact metal swarf accumulation would otherwise trap heat, score the bored wall, and cause sudden insert failure.\u003c\/p\u003e\n\u003cp\u003eWith its specialized 75-degree approach lead angle (K-type geometry), the tool pocket configuration is fine-tuned to balance cutting forces smoothly between axial and radial planes, drastically strengthening the insert cutting edge against sudden fracture. This unique force distribution allows for aggressive chip loads and heavy feed rates during extended-reach internal cycles. It is custom-machined to host highly rigid, double-sided 80-degree diamond negative indexable inserts, specifically the industry-standard \u003cstrong\u003eCNMG 120404 \/ CNMG 120408 \/ CNMG 120412\u003c\/strong\u003e series, giving operators 4 distinct working cutting edges per insert for superior cost efficiency on high-volume production lines. The compact, screw-down head geometry allows this heavy 20mm tool holder to clean bores down to an optimized \u003cstrong\u003e25mm minimum bore diameter\u003c\/strong\u003e. Combined with targeted double-sided chipbreaker geometries (such as premium negative -PM\/-DM profiles for carbon steels or -EM for sticky stainless alloys), this tooling configuration tightly curls long swarf ribbons into crisp \"C\"-shaped chips, pushing them smoothly out of the bore channel to preserve part dimensions and critical surface integrity.\u003c\/p\u003e\n\u003cdiv style=\"border: 2px solid #47479F; border-radius: 6px; padding: 20px; margin: 25px 0; background-color: #fbfbfe;\"\u003e\n\u003ch3 style=\"margin-top: 0; color: #47479f; font-size: 16px; border-bottom: 1px solid #e0e0e0; padding-bottom: 8px;\"\u003eModel Nomenclature Decoder: S20R-SCKNR12 (ISO \/ National Standard Chart Compliant)\u003c\/h3\u003e\n\u003cdiv style=\"margin-top: 12px; font-family: monospace; font-size: 13px;\"\u003e\n\u003cdiv style=\"display: block; margin-bottom: 6px; border: 1px solid #cccccc; padding: 8px; border-radius: 4px; background: #ffffff;\"\u003e\n\u003cstrong\u003eS\u003c\/strong\u003e - Solid High-Tensile Structural Alloy Steel Body Core (No through-coolant hole)\u003c\/div\u003e\n\u003cdiv style=\"display: block; margin-bottom: 6px; border: 1px solid #cccccc; padding: 8px; border-radius: 4px; background: #ffffff;\"\u003e\n\u003cstrong\u003e20\u003c\/strong\u003e - 20mm Precision Cylindrical Clamping Shank Diameter (Heavy industrial rigidity standard)\u003c\/div\u003e\n\u003cdiv style=\"display: block; margin-bottom: 6px; border: 1px solid #cccccc; padding: 8px; border-radius: 4px; background: #ffffff;\"\u003e\n\u003cstrong\u003eR\u003c\/strong\u003e - 200mm Industrial Standard Total Tool Core Length (Extended deep reach specification)\u003c\/div\u003e\n\u003cdiv style=\"display: block; margin-bottom: 6px; border: 1px solid #47479F; padding: 8px; border-radius: 4px; background: #f0f2f5; color: #333333;\"\u003e\n\u003cstrong\u003eS\u003c\/strong\u003e - \u003cstrong\u003eScrew Fastening Method\u003c\/strong\u003e (Streamlined profile, opens maximum chip clearance room for internal cuts)\u003c\/div\u003e\n\u003cdiv style=\"display: block; margin-bottom: 6px; border: 1px solid #cccccc; padding: 8px; border-radius: 4px; background: #ffffff;\"\u003e\n\u003cstrong\u003eC\u003c\/strong\u003e - 80° Diamond Geometric Negative Insert Shape Pocket Seating (CNMG 1204 format)\u003c\/div\u003e\n\u003cdiv style=\"display: block; margin-bottom: 6px; border: 1px solid #47479F; padding: 8px; border-radius: 4px; background: #f0f2f5; color: #333333;\"\u003e\n\u003cstrong\u003eK\u003c\/strong\u003e - \u003cstrong\u003e75° Approach Lead Angle\u003c\/strong\u003e (Distributes load smoothly for heavy interrupted cutting and maximized edge strength)\u003c\/div\u003e\n\u003cdiv style=\"display: block; margin-bottom: 6px; border: 1px solid #47479F; padding: 8px; border-radius: 4px; background: #47479F; color: #ffffff;\"\u003e\n\u003cstrong\u003eN\u003c\/strong\u003e - \u003cstrong\u003e0° Normal Relief Clearance Angle\u003c\/strong\u003e (Heavy-duty negative insert layout providing double-sided 4-edge usability)\u003c\/div\u003e\n\u003cdiv style=\"display: block; margin-bottom: 6px; border: 1px solid #cccccc; padding: 8px; border-radius: 4px; background: #ffffff;\"\u003e\n\u003cstrong\u003eR\u003c\/strong\u003e - \u003cstrong\u003eRight-Hand Tool Cutting Rotation Direction\u003c\/strong\u003e (Standard forward M03 internal turning toolpath)\u003c\/div\u003e\n\u003cdiv style=\"display: block; border: 1px solid #47479F; padding: 8px; border-radius: 4px; background: #47479F; color: #ffffff;\"\u003e\n\u003cstrong\u003e12\u003c\/strong\u003e - Accommodates Standard 12mm Cutting Edge Length Inserts (CNMG 120404 \/ CNMG 120408)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 2px solid #47479F; border-radius: 6px; padding: 15px; margin-bottom: 25px; background-color: #47479f; color: #ffffff; text-align: center;\"\u003e\n\u003cp style=\"margin: 0 0 10px 0; font-weight: bold; font-size: 16px;\"\u003eOperating counter-boring cycles or left-hand toolpaths on sub-spindles?\u003c\/p\u003e\n\u003cspan style=\"color: #47479f;\"\u003e\u003cspan style=\"display: inline-block; background-color: rgb(255, 255, 255); padding: 8px 20px; border-radius: 4px; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;\"\u003e\u003cb\u003e \u003ca href=\"https:\/\/cnchome-beyond.com\/search?q=CNMG1204\" target=\"_blank\" rel=\"noopener\"\u003eSwitch to the Mirror S20R-SCKNL12 (Left Hand) Tool Bar → \u003c\/a\u003e\u003c\/b\u003e\u003c\/span\u003e\u003c\/span\u003e\n\u003c\/div\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e2. Product Core Advantages\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eLow-Profile S-Type Screw Clamping:\u003c\/strong\u003e Locks the negative insert securely through its center hole. Eliminates bulky external clamps, ensuring zero chip nesting and flawless evacuation inside narrow bores.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUltra-Rigid 20mm Solid Alloy Core:\u003c\/strong\u003e Hardened to HRC 42-45 to actively absorb mechanical harmonics, completely eliminating tool deflection during heavy internal cutting passes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHeavy-Load 75° Lead Angle:\u003c\/strong\u003e Balances mechanical cutting forces efficiently, relieving radial pressure to prevent micro-chatter lines during heavy-duty internal roughing cycles.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDouble-Sided 4-Edge Cost Reduction:\u003c\/strong\u003e Custom engineered for negative 80° diamond CNMG 1204 inserts, delivering 4 working cutting edges per insert to cut your workshop's consumable costs by up to 50%.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndustrial Black Oxide Barrier:\u003c\/strong\u003e Treated with a high-temperature chemical oxidation coat to resist severe abrasive chip friction and protect precision insert pocket indexing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e3. Technical Specification Parameters \u0026amp; Model Comparison\u003c\/h2\u003e\n\u003cdiv style=\"overflow-x: auto; margin-bottom: 20px;\"\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; min-width: 500px; font-size: 14px;\"\u003e\n\u003cthead\u003e\n\u003ctr style=\"background-color: #47479f; color: #ffffff;\"\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003eTechnical Blueprint Field\u003c\/th\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003eMetric Blueprint Value (S20R-SCKNR12)\u003c\/th\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003eImperial Inch Equivalent Model Reference\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eClamping Shank Diameter (φ d)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e\u003cstrong\u003e20 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e0.7874 inches (Fits standard 20mm CNC round boring sleeves or 3\/4-inch turret bushings)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eOverall Tool Length (L)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e\u003cstrong\u003e200 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e7.8740 inches total tool length (R-Type industrial extended deep reach series)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eMinimum Machining Bore (φ Dmin)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e\u003cstrong\u003e25 mm\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e0.9842 inches entry clearance circle line for structural safety\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eCompatible Indexable Insert Sizing\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e\u003cstrong\u003eCNMG 120404 \/ CNMG 120408 \/ CNMG 120412\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eCNMG 431 \/ CNMG 432 \/ CNMG 433 (Double-sided negative standard)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eMatching Fasteners \u0026amp; Spares Included\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eHardened Shim, Shim Screw, Center Insert Lock Screw \u0026amp; Torx Wrench\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eStandard globally interchangeable S-type hardware assembly\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003ch3 style=\"color: #333; font-size: 16px; margin-top: 20px;\"\u003eIndustrial Cutting Feed \u0026amp; Speed Data Recommendation Table\u003c\/h3\u003e\n\u003cdiv style=\"overflow-x: auto; margin-bottom: 25px;\"\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; min-width: 500px; font-size: 14px;\"\u003e\n\u003cthead\u003e\n\u003ctr style=\"background-color: #eef0f7; color: #47479f;\"\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003eISO Workpiece Material Group\u003c\/th\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003eCutting Speed (Vc) Range\u003c\/th\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003eRecommended Feed Rate (fn)\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eMedium Carbon Steel (P-Class \/ AISI 1045)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e140 - 220 m\/min\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e0.15 - 0.35 mm\/rev\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eAlloy Steel \/ Die Mold Steel (P-Class \/ 42CrMo)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e110 - 180 m\/min\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e0.12 - 0.30 mm\/rev\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eAustenitic Stainless Steels (M-Class \/ SS304)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e80 - 140 m\/min\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e0.10 - 0.22 mm\/rev\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold;\"\u003eNodular \/ Gray Cast Iron (K-Class \/ GG20)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e100 - 170 m\/min\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003e0.15 - 0.38 mm\/rev\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e4. Product Application Scenarios\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e75-Degree Heavy Internal Roughing:\u003c\/strong\u003e The 75-degree lead angle optimizes chip thickness and protects the insert corner radius, allowing massive material removal rates in steel forgings.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSevere Interrupted Boring Cycles:\u003c\/strong\u003e The rigid 20mm alloy core combined with flat negative pocket seating easily absorbs heavy impact loads when boring across cross-holes or multi-splined inner diameters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExtended deep-reach boring profiling:\u003c\/strong\u003e 200mm extended length allows deep cavity longitudinal boring inside large cylinder liners and structural mechanical blocks without chatter lines.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e5. Equipment Tooling Compatibility Matrix\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e20mm \/ 3\/4-inch CNC Turrets:\u003c\/strong\u003e Fits smoothly into standard metric 20mm boring block stations or standard imperial 3\/4-inch round split-sleeve reduction block sets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eISO Standard Size-12 Negative Inserts:\u003c\/strong\u003e Precision-machined pocket seat perfectly anchors all standard 80° diamond negative inserts designated by global codes **CNMG 1204--**.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e6. BEYOND Premium Carbide Grade Selection Guide\u003c\/h2\u003e\n\u003cdiv style=\"overflow-x: auto; margin-bottom: 25px;\"\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; min-width: 500px; font-size: 14px;\"\u003e\n\u003cthead\u003e\n\u003ctr style=\"background-color: #47479f; color: #ffffff;\"\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003eBEYOND Cutting Insert Grade\u003c\/th\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003eCoating Micro-Structure Matrix\u003c\/th\u003e\n\u003cth style=\"padding: 10px; border: 1px solid #dddddd; text-align: left;\"\u003ePrimary Application Strengths\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold; color: #47479f;\"\u003eBYM11 (CVD Grade)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eThick Double-Layer Al2O3 + TiCN Thermal Barrier\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eEngineered for high-speed, high-temperature continuous dry roughing of hard carbon steels, tool alloys, and cast irons. Highly wear-resistant.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold; color: #47479f;\"\u003eBYS25 (PVD Grade)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eSub-Micron Multi-Layered Nano-TiAlN Coating Shield\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eSuperb edge toughness. Best optimized for severe interrupted cuts, tough stainless steel series (SS304\/316), and superalloys.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd; font-weight: bold; color: #47479f;\"\u003eBYK15 (Uncoated Polished)\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eMirror-Finished Sharp Micro-Grain Solid Carbide Matrix\u003c\/td\u003e\n\u003ctd style=\"padding: 10px; border: 1px solid #dddddd;\"\u003eZero Built-Up Edge (BUE) formation. Specially developed for high-speed, precision mirror boring of aluminum, brass, and plastics.\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e7. Why Choose BEYOND CNC Machine Tools?\u003c\/h2\u003e\n\u003cp\u003eBEYOND delivers premium-engineered, industrial-grade indexable tool holders trusted by manufacturing facilities worldwide. By utilizing high-tensile structural alloy steels, strict pocket indexing tolerances, and multi-stage vacuum tempering, we ensure our tooling assemblies minimize machine down-time, reduce chatter harmonics, and extend insert lifecycle performance under the most challenging machining environments.\u003c\/p\u003e\n\u003ch3 style=\"color: #333; font-size: 16px; margin-top: 20px;\"\u003eGlobal Machinist Operational Reviews\u003c\/h3\u003e\n\u003cdiv style=\"display: block; margin-bottom: 25px;\"\u003e\n\u003cdiv style=\"border: 1px solid #e0e0e0; padding: 15px; border-radius: 6px; background-color: #ffffff; margin-bottom: 12px;\"\u003e\n\u003cdiv style=\"color: #ffcc00; font-size: 16px; margin-bottom: 5px;\"\u003e★★★★★\u003c\/div\u003e\n\u003cp style=\"margin: 0 0 8px 0; font-size: 13px; font-weight: bold;\"\u003eMarcus D. — United States\u003c\/p\u003e\n\u003cp style=\"margin: 0; font-size: 13px; color: #555;\"\u003e\"The S20R-SCKNR12 functions perfectly in our 3\/4 CNC turret block. Running heavy roughing passes with negative CNMG 1204 inserts on this 20mm bar is incredibly stable. The 75-degree approach angle splits the cutting pressure brilliantly.\"\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e0e0e0; padding: 15px; border-radius: 6px; background-color: #ffffff; margin-bottom: 12px;\"\u003e\n\u003cdiv style=\"color: #ffcc00; font-size: 16px; margin-bottom: 5px;\"\u003e★★★★★\u003c\/div\u003e\n\u003cp style=\"margin: 0 0 8px 0; font-size: 13px; font-weight: bold;\"\u003eJürgen S. — Germany\u003c\/p\u003e\n\u003cp style=\"margin: 0; font-size: 13px; color: #555;\"\u003e\"Phänomenale Steifigkeit. We run this for massive internal roughing cycles on carbon forgings. Because it uses the S-type screw method for CNMG negative inserts, there is no top clamp to block the bore path. Chips spiral right out of the channel.\"\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e0e0e0; padding: 15px; border-radius: 6px; background-color: #ffffff; margin-bottom: 12px;\"\u003e\n\u003cdiv style=\"color: #ffcc00; font-size: 16px; margin-bottom: 5px;\"\u003e★★★★★\u003c\/div\u003e\n\u003cp style=\"margin: 0 0 8px 0; font-size: 13px; font-weight: bold;\"\u003eKenji T. — Japan\u003c\/p\u003e\n\u003cp style=\"margin: 0; font-size: 13px; color: #555;\"\u003e\"Pocket geometry is incredibly precise for negative inserts. Being able to run heavy-duty double-sided CNMG 1204 inserts with 4 cutting edges on a standard 20mm internal bar saves our shop a massive amount of money.\"\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e0e0e0; padding: 15px; border-radius: 6px; background-color: #ffffff; margin-bottom: 12px;\"\u003e\n\u003cdiv style=\"color: #ffcc00; font-size: 16px; margin-bottom: 5px;\"\u003e★★★★☆\u003c\/div\u003e\n\u003cp style=\"margin: 0 0 8px 0; font-size: 13px; font-weight: bold;\"\u003eMatteo V. — Italy\u003c\/p\u003e\n\u003cp style=\"margin: 0; font-size: 13px; color: #555;\"\u003e\"Great dampening properties on interrupted cuts for tough alloy blocks. The 75-degree lead prevents sudden insert corner fractures perfectly. High-quality hard plating on the pocket body.\"\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"border: 1px solid #e0e0e0; padding: 15px; border-radius: 6px; background-color: #ffffff;\"\u003e\n\u003cdiv style=\"color: #ffcc00; font-size: 16px; margin-bottom: 5px;\"\u003e★★★★★\u003c\/div\u003e\n\u003cp style=\"margin: 0 0 8px 0; font-size: 13px; font-weight: bold;\"\u003eOliver P. — United Kingdom\u003c\/p\u003e\n\u003cp style=\"margin: 0; font-size: 13px; color: #555;\"\u003e\"Top tier industrial tool holder. Shipped complete with hardened seat shims and wrenches. Holds indexing repeatability perfectly after rotating worn CNMG edges.\"\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e8. AI-Style Engineering Support Engine (FAQ)\u003c\/h2\u003e\n\u003cdiv style=\"margin-bottom: 15px; padding: 12px; background-color: #f9f9f9; border-radius: 4px;\"\u003e\n\u003cp style=\"margin: 0 0 5px 0; font-weight: bold; color: #47479f;\"\u003eQ1: Why choose an S-type screw-clamped boring bar for heavy negative CNMG inserts instead of a top clamp?\u003c\/p\u003e\n\u003cp style=\"margin: 0; color: #444;\"\u003eA1: Inside tighter bores (25mm-45mm), traditional top clamp mechanisms stick up too far, catching long stringy chips and causing catastrophic tool packing or insert breakage. The S-type center screw locks the thick negative CNMG insert firmly from within its bore hole, maintaining a completely flush head profile for maximum chip evacuation room.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-bottom: 15px; padding: 12px; background-color: #f9f9f9; border-radius: 4px;\"\u003e\n\u003cp style=\"margin: 0 0 5px 0; font-weight: bold; color: #47479f;\"\u003eQ2: What is the absolute minimum bore entry boundary for this S20R-SCKNR12 tool holder?\u003c\/p\u003e\n\u003cp style=\"margin: 0; color: #444;\"\u003eA2: The absolute minimum machining bore diameter (φ Dmin) is 25.0mm (0.984 inches). Running this tool holder inside any bore smaller than 25mm will cause the steel clearance flank beneath the pocket to scrape heavily against the workpiece wall, ruining your dimensional accuracy.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-bottom: 15px; padding: 12px; background-color: #f9f9f9; border-radius: 4px;\"\u003e\n\u003cp style=\"margin: 0 0 5px 0; font-weight: bold; color: #47479f;\"\u003eQ3: What role does the \"K\" approach angle play regarding cutting performance and tool life?\u003c\/p\u003e\n\u003cp style=\"margin: 0; color: #444;\"\u003eA3: The \"K\" signifies a 75° approach lead angle. Unlike a 95° bar which pushes forces radially, the 75° orientation spreads the cutting pressure across a longer section of the insert edge, maximizing strength and protecting the tip during high-feed roughing or heavily interrupted cuts.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003ch2 style=\"color: #47479f; font-size: 20px; border-bottom: 2px solid #47479F; padding-bottom: 5px; margin-top: 30px;\"\u003e9. Technical Maintenance \u0026amp; Troubleshooting Guidelines\u003c\/h2\u003e\n\u003cdiv style=\"margin-top: 15px;\"\u003e\n\u003cdiv style=\"background-color: #f0f2f5; padding: 15px; border-radius: 4px; margin-bottom: 12px;\"\u003e\n\u003ch4 style=\"margin: 0 0 8px 0; color: #333; font-size: 14px; border-left: 3px solid #47479F; padding-left: 8px;\"\u003eEquivalent Industry Models\u003c\/h4\u003e\n\u003cp style=\"margin: 0; font-size: 12px; color: #555;\"\u003eInterchangeable globally with standard international metric \u003cstrong\u003eS20R-SCKNR12\u003c\/strong\u003e internal boring tool holder assemblies. For American imperial lathe turrets, this 20mm metric steel bar functions smoothly within standard 3\/4-inch round split bushings or block adapters, utilizing standard ANSI negative indexable insert designations **CNMG 431** or **CNMG 432**.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background-color: #f0f2f5; padding: 15px; border-radius: 4px; margin-bottom: 12px;\"\u003e\n\u003ch4 style=\"margin: 0 0 8px 0; color: #333; font-size: 14px; border-left: 3px solid #47479F; padding-left: 8px;\"\u003eTroubleshooting Tips\u003c\/h4\u003e\n\u003cp style=\"margin: 0; font-size: 12px; color: #555;\"\u003e\u003cstrong\u003eMicro-Vibration \/ Surface Finish Lines:\u003c\/strong\u003e Ensure the center height of the boring bar tip is aligned precisely with the lathe spindle centerline (±0.1mm). Incorrect centerline height changes the active cutting clearance angle, accelerating nose wear.\u003cbr\u003e\u003cstrong\u003eScrew Binding Prevention:\u003c\/strong\u003e Due to localized thermal expansion during continuous cycles, clean the pocket and apply standard anti-seize paste compound to the Torx hardware threads regularly.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background-color: #f0f2f5; padding: 15px; border-radius: 4px;\"\u003e\n\u003ch4 style=\"margin: 0 0 8px 0; color: #333; font-size: 14px; border-left: 3px solid #47479F; padding-left: 8px;\"\u003eWorkpiece Material Matrix\u003c\/h4\u003e\n\u003cp style=\"margin: 0; font-size: 12px; color: #555;\"\u003eFully optimized across standard industrial engineering alloy group codes: \u003cstrong\u003eP\u003c\/strong\u003e (Carbon, Low-Alloy \u0026amp; Pre-hardened Mold Steels), \u003cstrong\u003eM\u003c\/strong\u003e (Austenitic, Ferritic \u0026amp; Duplex Stainless Grades), \u003cstrong\u003eK\u003c\/strong\u003e (High-Tensile Grey, Nodular \u0026amp; Ductile Cast Irons), \u003cstrong\u003eN\u003c\/strong\u003e (Aluminum Casting Blanks, Copper Alloys \u0026amp; Non-ferrous Polymers), and \u003cstrong\u003eS\u003c\/strong\u003e (Titanium Alloys, Inconel \u0026amp; Heat-Resistant Superalloys).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"BEYOND","offers":[{"title":"Default Title","offer_id":43590819872940,"sku":"S20R-SCKNR12","price":21.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0592\/7328\/1708\/files\/BEYOND_S20R-SCKNR12_indexable_screw-clamped_right-hand_internal_boring_bar_with_20mm_steel_shank_200mm_length_and_75-degree_approach_angle_for_negative_CNMG_120404_carbide_inserts.jpg?v=1781160986","url":"https:\/\/cnchome-beyond.com\/products\/beyond-s20r-scknr12-boring-bar-tool-holder","provider":"CNCHome-Beyond","version":"1.0","type":"link"}