{"product_id":"hertel-66691528-screw-machine-drill-bit-letter-b-cobalt","title":"Hertel 66691528 Screw Machine Drill Bit Letter B Cobalt","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\u003cp\u003eThe HERTEL 66691528 is a screw machine length drill bit designed for high-production drilling in tough materials. Built from cobalt high-speed steel with a titanium nitride (TiN) coating, this bit delivers extended tool life and heat resistance in demanding shop and field applications. It measures 2.5 inches in overall length with a 1.375-inch flute length and a 0.2380-inch diameter, corresponding to Letter B sizing. The 135-degree split point reduces walking on contact and requires less thrust to start a hole, making it well-suited for harder workpiece materials. Web-thinned construction further lowers cutting resistance. It is sold and packaged as a single bit.\u003c\/p\u003e\u003cp\u003eThis drill bit is intended for metalworking applications where a short, rigid drill is preferred over jobber-length tooling. Screw machine length bits are commonly used in CNC lathes, turret lathes, drill presses, and automatic screw machines where tool overhang must be minimized to maintain precision and reduce deflection. The cobalt substrate and TiN coating make it appropriate for drilling stainless steel, alloy steel, cast iron, and other abrasion-resistant metals. The right-hand spiral flute and straight cylindrical shank allow direct mounting in standard drill chucks and collets without additional toolholding adapters.\u003c\/p\u003e\u003ch4\u003eKey Features\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eCobalt steel construction with TiN coating for extended wear life in hard and abrasive materials\u003c\/li\u003e\n\u003cli\u003e135-degree split point reduces thrust requirements and minimizes bit walking at entry\u003c\/li\u003e\n\u003cli\u003eWeb-thinned, parallel-web design lowers cutting resistance throughout the flute\u003c\/li\u003e\n\u003cli\u003eScrew machine length geometry increases rigidity and reduces deflection in close-tolerance drilling\u003c\/li\u003e\n\u003cli\u003eRight-hand spiral flute for standard chip evacuation in conventional drilling operations\u003c\/li\u003e\n\u003cli\u003eStraight cylindrical shank at 0.2380 inches fits standard drill chucks and collets directly\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eCompatibility\u003c\/h4\u003e\u003cp\u003eDesigned as an OEM-style replacement or standard tooling selection for use in drill presses, CNC lathes, turret lathes, and automatic screw machines accepting a straight cylindrical shank at 0.2380 inches diameter.\u003c\/p\u003e\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\u003cp\u003eInstallation is performed by machinists and toolroom technicians. De-energize and lock out all power to the machine before changing tooling, in accordance with OSHA lockout\/tagout procedures. Ensure the shank is fully seated and the chuck or collet is tightened to the machine specification before operation. Do not use this bit without coolant or cutting fluid when drilling hard alloys, as dry cutting will reduce coating life and may cause premature edge failure.\u003c\/p\u003e\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrill Bit Size\u003c\/strong\u003e: Letter B\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiameter (Decimal)\u003c\/strong\u003e: 0.2380 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOverall Length\u003c\/strong\u003e: 2.5 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlute Length\u003c\/strong\u003e: 1.375 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrill Point Angle\u003c\/strong\u003e: 135 degrees\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePoint Type\u003c\/strong\u003e: Split\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTool Material\u003c\/strong\u003e: Cobalt\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoating\/Finish\u003c\/strong\u003e: TiN (Titanium Nitride)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShank Type\u003c\/strong\u003e: Straight-Cylindrical\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShank Diameter\u003c\/strong\u003e: 0.2380 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCutting Direction\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlute Type\u003c\/strong\u003e: Spiral\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpiral Type\u003c\/strong\u003e: Regular\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeb Configuration\u003c\/strong\u003e: Parallel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeb Thinning\u003c\/strong\u003e: Web-Thinned\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrill Bit Grade\u003c\/strong\u003e: Heavy Duty\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: 0.1 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUNSPSC Code\u003c\/strong\u003e: 23241635\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eStandard Information\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: HERTEL\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 66691528\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"HERTEL","offers":[{"title":"Default Title","offer_id":51741288890674,"sku":"66691528","price":14.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/d9f4a3f8000dbde7d8b62832006bc2c0.jpg?v=1788830560","url":"https:\/\/voomisupply.com\/products\/hertel-66691528-screw-machine-drill-bit-letter-b-cobalt","provider":"Voomi Supply","version":"1.0","type":"link"}