{"product_id":"chicago-latrobe-54058-cobalt-drill-bit-letter-e-1-4-in","title":"Chicago-latrobe 54058 Cobalt Drill Bit Letter E 1\/4 in","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe CHICAGO-LATROBE 54058 is a cobalt jobber length drill bit in Letter E size, equivalent to 0.2500 inches in diameter. Built to Series 2550 standards and conforming to DIN 338 and NAS 907 Type J specifications, this bit is engineered for high-performance drilling in tough materials including stainless steel and hardened steels. The M42 cobalt construction is paired with a titanium nitride (TiN) coating for extended wear resistance. The 135-degree split point geometry reduces walking and lowers feed pressure at entry, making it well suited for production environments and maintenance shops where precision and tool life matter.\u003c\/p\u003e\n\u003cp\u003eThis bit is designed for drilling stainless steel and steel in demanding applications where standard high-speed steel tooling falls short. The regular spiral flute and right-hand cut make it compatible with standard drill presses, CNC machining centers, and hand-held power tools. Machinists, maintenance technicians, pipefitters, and fabricators working in industrial, commercial, and trade settings will find the 54058 appropriate for hole-making tasks where bit longevity and dimensional accuracy are priorities. The tapered web with web thinning further reduces cutting resistance in deep-hole and interrupted-cut scenarios.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003eM42 cobalt construction for superior heat and wear resistance in hard materials\u003c\/li\u003e\n  \u003cli\u003eTiN coating extends tool life and reduces friction at the cutting edge\u003c\/li\u003e\n  \u003cli\u003e135-degree split point minimizes walking and reduces required feed force\u003c\/li\u003e\n  \u003cli\u003eWeb-thinned, tapered web lowers cutting resistance in deep or interrupted cuts\u003c\/li\u003e\n  \u003cli\u003eStraight-cylindrical shank fits standard 3-jaw chucks without adapters\u003c\/li\u003e\n  \u003cli\u003eMeets DIN 338 and NAS 907 Type J standards for dimensional consistency\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned as an OEM-style replacement or direct-use jobber length drill bit for applications requiring a Letter E (0.2500 inch) diameter hole in stainless steel or steel workpieces. Fits any standard drill chuck accepting a 1\/4 inch straight-cylindrical shank.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eInstallation of this bit should be performed by machinists or qualified technicians familiar with proper chuck-mounting procedures and appropriate cutting speeds for cobalt tooling. Secure the shank fully in the chuck before applying power and verify chuck key is removed prior to starting the machine. Use cutting fluid or coolant appropriate for stainless steel when possible to preserve coating and edge life. Do not exceed the recommended surface footage for cobalt M42 tooling in hard materials, as excessive speed generates heat that shortens tool life.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDrill Bit Size (Letter)\u003c\/strong\u003e: E\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDrill Bit Size (Decimal Inch)\u003c\/strong\u003e: 0.2500 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial Grade\u003c\/strong\u003e: M42 Cobalt\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCoating\u003c\/strong\u003e: Titanium Nitride (TiN)\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\u003eFlute Type\u003c\/strong\u003e: Spiral, Regular\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNumber of Flutes\u003c\/strong\u003e: 2\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCutting Direction\u003c\/strong\u003e: Right Hand\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOverall Length\u003c\/strong\u003e: 4 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlute Length\u003c\/strong\u003e: 2.75 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShank Diameter\u003c\/strong\u003e: 0.2500 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShank Length\u003c\/strong\u003e: 1.2500 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShank Type\u003c\/strong\u003e: Straight-Cylindrical\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWeb Configuration\u003c\/strong\u003e: Tapered, Web-Thinned\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: 2550\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eStandards\u003c\/strong\u003e: DIN 338, NAS 907 Type J\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePrimary Workpiece Material\u003c\/strong\u003e: Stainless Steel, Steel\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCoolant Through\u003c\/strong\u003e: No\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDiameter Tolerance\u003c\/strong\u003e: -0.0007 to 0.0000 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGrade\u003c\/strong\u003e: Heavy Duty\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUNSPSC Code\u003c\/strong\u003e: 23241634\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: CHICAGO-LATROBE\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 54058\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"CHICAGO-LATROBE","offers":[{"title":"Default Title","offer_id":51728068542770,"sku":"54058","price":18.87,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/21a70335fac90a142b9fe5b2845ddace.jpg?v=1788687359","url":"https:\/\/voomisupply.com\/products\/chicago-latrobe-54058-cobalt-drill-bit-letter-e-1-4-in","provider":"Voomi Supply","version":"1.0","type":"link"}