Chicago-latrobe 49021 Screw Machine Drill Bit 10mm Cobalt

Product Description

The CHICAGO-LATROBE 49021 is a screw machine length cobalt drill bit designed for high-production drilling in tough ferrous metals. Built from M42 cobalt high-speed steel with a straw oxide finish, this bit handles heat and wear in demanding shop environments. The 135-degree split point geometry reduces walking and lowers thrust force at entry, making it suitable for hand-feed and machine-feed applications. At 10.00 mm (0.3937 inches) in diameter with an overall length of 3.633 inches, the stub-length body delivers increased rigidity and reduced deflection compared to jobber-length alternatives. Two regular spiral flutes provide efficient chip evacuation. This is a right-hand cutting, straight shank bit built to DIN 1897 standards.

The 49021 is suited for drilling tool steel, alloyed steel, carbon steel, and cast iron in production machining, maintenance, and fabrication settings. Its screw machine (stub) length makes it a practical choice for drill press work, CNC machining centers, turret lathes, and manual mill operations where rigidity and hole accuracy are priorities. The heavy-duty grade and M42 material grade make it appropriate for interrupted cuts and work-hardening materials that would prematurely dull standard HSS bits. Maximum drilling depth is 1.378 inches, consistent with the stub-length flute design.

Key Features

• M42 cobalt high-speed steel construction for extended tool life in hard and abrasive metals
• 135-degree split point reduces thrust and eliminates center punch requirement on most materials
• Straw oxide coating provides mild lubricity and heat resistance
• Stub screw machine length increases rigidity and minimizes deflection in through-hole applications
• Two regular spiral flutes for reliable chip clearance
• Conforms to DIN 1897 specification for consistent geometry and interchangeability

Compatibility

Primary workpiece materials include tool steel, alloyed steel, carbon steel, and cast iron. The straight cylindrical shank (0.3937 inches diameter) fits standard drill chucks and collet holders sized for 10.00 mm shanks. Part of the Chicago-Latrobe Series 559 stub drill line covering the 9.50 mm to 11.00 mm diameter range.

Installation Notes

Installation and use should be performed by machinists or qualified tradespeople familiar with drill press, lathe, or milling machine operation. Secure the shank fully in a properly sized chuck or collet before operation and verify runout is within acceptable limits. Always power down and lock out the machine before changing bits. Do not exceed the recommended maximum drilling depth of 1.378 inches for this stub-length geometry without retracting to clear chips.