Chicago-latrobe 46621 Cobalt Jobber Drill Bit 21/64 in

Product Description

The CHICAGO-LATROBE 46621 is a cobalt jobber-length drill bit designed for high-performance drilling in hard and abrasive materials. Built from M42 cobalt high-speed steel, this bit carries a gold oxide coating and features a 135-degree split point that reduces walking and cutting pressure at startup. The right-hand spiral flute geometry promotes efficient chip evacuation during through-hole drilling. At 4-5/8 inches overall length with a 3-5/16-inch flute, it fits standard jobber-length chucks and drill presses used in trade and industrial shops. The straight-cylindrical shank measures 0.3281 inches in diameter and seats securely in keyed or keyless chucks.

This bit is rated for drilling titanium and other difficult primary workpiece materials where standard HSS bits lose edge life quickly. The Series 550 heavy-duty designation and NAS 907 Type J and DIN 338 compliance make it appropriate for aerospace, mechanical, and general fabrication work where dimensional tolerance and consistent geometry are required. Trades including pipefitters, millwrights, sheet metal mechanics, and maintenance technicians rely on cobalt bits like this one when working through hardened fastener stock, stainless, or exotic alloys on the job or at the bench.

Key Features

• M42 cobalt steel construction for extended edge life in hard materials
• 135-degree split point reduces thrust and eliminates center-punch requirement on most materials
• Gold oxide finish provides lubricity and corrosion resistance during cutting
• Web-thinned, tapered web configuration reduces cutting resistance
• Regular spiral flute with right-hand cut for standard drill press and hand drill use
• Meets DIN 338 and NAS 907 Type J standards for dimensional accuracy

Compatibility

Designed as an OEM-style replacement or direct-use jobber drill bit for any application requiring a 21/64-inch diameter, straight-cylindrical shank bit compatible with standard three-jaw keyed or keyless chucks.

Installation Notes

This bit is installed by a qualified machinist, fabricator, or trade technician using a standard drill press, magnetic drill, or hand drill with appropriate chuck capacity. Secure the shank fully in the chuck before applying power and confirm the workpiece is clamped or fixtured before beginning the cut. Use cutting fluid when drilling titanium or stainless steel to preserve edge life and manage heat. Inspect the cutting edges before each use and replace any bit showing chipping or heat discoloration at the point.