{"product_id":"precision-twist-drill-5997729-cobalt-jobber-drill-no-28","title":"Precision Twist Drill 5997729 Cobalt Jobber Drill No. 28","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe PRECISION TWIST DRILL 5997729 is a cobalt jobber-length drill bit sized to No. 28 wire gauge (9\/64 inch, 0.1406 inch decimal) designed for drilling steel and other hard workpiece materials. It features a 135-degree split point with web thinning for fast engagement and reduced walking on entry. The straw oxide finish provides light lubricity and corrosion resistance during cutting operations. At 2.875 inches overall length with a 1.75-inch flute, this is a standard jobber geometry suited for general-purpose drilling in production and maintenance environments. The straight cylindrical shank accepts standard drill chucks without any adapter.\u003c\/p\u003e\n\u003cp\u003eThis drill bit is intended for drilling steel, cast iron, nonferrous metals, and similar materials classified under workpiece material codes P, M, K, N, and S. It is well-suited for use in drill presses, hand drills, and CNC machining centers where a straight-shank jobber bit is specified. The heavy-duty cobalt construction makes it appropriate for harder steels and interrupted cuts where standard high-speed steel bits lose their edge prematurely. Machinists, maintenance technicians, pipefitters, and fabricators typically reach for this size when drilling pilot holes, clearance holes, or through-holes in structural steel components.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003eCobalt construction for extended tool life in hard and abrasive steels\u003c\/li\u003e\n  \u003cli\u003e135-degree split point with web thinning reduces thrust and prevents walking\u003c\/li\u003e\n  \u003cli\u003eStraw oxide finish provides light lubricity and surface protection\u003c\/li\u003e\n  \u003cli\u003eRegular spiral flute geometry at 12xD ratio for efficient chip evacuation\u003c\/li\u003e\n  \u003cli\u003eStraight cylindrical shank fits standard drill chucks without adapters\u003c\/li\u003e\n  \u003cli\u003eMeets ANSI and NAS 907 standards for consistent dimensional accuracy\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003ePart of the R10CO-R15CO-R18CO series. Designed as an OEM-style replacement or direct substitution for No. 28 wire-gauge jobber drill bits in any standard drill chuck accepting a 0.1406-inch straight shank.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eSecure the shank fully into the drill chuck and confirm the bit is centered before applying power. Use appropriate cutting fluid or coolant when drilling steel to extend bit life and maintain dimensional accuracy. Always wear eye protection and clamp the workpiece securely before drilling. Cobalt bits should not be run at excessively high RPM without lubrication, as heat buildup accelerates edge wear.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDrill Bit Size (Wire)\u003c\/strong\u003e: No. 28\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDrill Bit Size (Inch)\u003c\/strong\u003e: 9\/64 inch\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDrill Bit Size (Decimal Inch)\u003c\/strong\u003e: 0.1406 inch\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDrill Bit Material\u003c\/strong\u003e: Cobalt\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: Standard split point, web-thinned\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCoating\/Finish\u003c\/strong\u003e: Straw oxide\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlute Type\u003c\/strong\u003e: Regular spiral\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: 2.875 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlute Length\u003c\/strong\u003e: 1.75 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaximum Drilling Depth\u003c\/strong\u003e: 1.75 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShank Diameter\u003c\/strong\u003e: 0.1406 inch\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eShank Length\u003c\/strong\u003e: 1.125 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\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlute-to-Diameter Ratio\u003c\/strong\u003e: 12xD\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePrimary Workpiece Material\u003c\/strong\u003e: Steel (codes P, M, K, N, S)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTool Performance\u003c\/strong\u003e: General purpose, heavy duty\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCoolant Through\u003c\/strong\u003e: No\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDouble Margin\u003c\/strong\u003e: No\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSeries\u003c\/strong\u003e: R10CO-R15CO-R18CO\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eStandards\u003c\/strong\u003e: ANSI, NAS 907\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePackage Weight\u003c\/strong\u003e: 0.042 pounds\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePackage Quantity\u003c\/strong\u003e: 1\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: PRECISION TWIST DRILL\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 5997729\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"PRECISION TWIST DRILL","offers":[{"title":"Default Title","offer_id":51711038357810,"sku":"5997729","price":14.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/fd6336b34c1d0261f5eb3b4d3e77059f_b1e3e418-d8dd-4e63-85c7-91975d3bd216.jpg?v=1788473804","url":"https:\/\/voomisupply.com\/products\/precision-twist-drill-5997729-cobalt-jobber-drill-no-28","provider":"Voomi Supply","version":"1.0","type":"link"}