Chicago-latrobe 50863 Cobalt Screw Machine Drill Bit 0.199 in

Product Description

The CHICAGO-LATROBE 50863 is a cobalt screw machine length drill bit designed for heavy-duty metal drilling applications. Sized at 0.199 inches (Wire Size #8) in diameter, it features a 135-degree split point that reduces walking and allows for fast, clean starts without a center punch on most materials. The M42 cobalt steel construction gives it the heat resistance needed for sustained drilling in tough materials. At 2.25 inches overall length with a 1.1875-inch flute, this stub-length geometry provides rigidity and reduced deflection compared to jobber-length bits. Licensed tradespeople and machinists working in metal fabrication, maintenance, and repair rely on this format for precision hole work in confined setups.

This bit is built for drilling cast iron and steel, including harder alloy grades that would dull standard high-speed steel tooling quickly. The screw machine (stub) length format makes it well-suited for drill press work, CNC operations, turret setups, and hand-drill applications where a shorter bit column improves accuracy. The two-flute spiral design with web-thinned, parallel web geometry clears chips efficiently during through-hole and blind-hole drilling. Series 559 bits from CHICAGO-LATROBE are sized to ISO standards and carry a heavy-duty grade rating appropriate for production and repetitive drilling cycles.

Key Features

• M42 cobalt construction for heat resistance in hard metals including alloy steel and cast iron
• 135-degree split point reduces thrust and eliminates walking on entry
• Web-thinned parallel web lowers cutting resistance and improves chip clearance
• Screw machine (stub) length at 2.25 inches overall provides added rigidity and reduced deflection
• Straight-cylindrical shank fits standard three-jaw chucks and collet systems without modification
• Right-hand cut, two-flute spiral flute design compatible with standard drill press and hand-drill rotation

Compatibility

Designed for use in standard straight-shank drill chucks on drill presses, CNC turrets, hand drills, and similar machine tool spindles. Primary workpiece materials are cast iron and steel per manufacturer specification.

Installation Notes

Secure the bit fully in the chuck before use and verify there is no runout before beginning a cut. Always power down the machine and lock out energy before changing bits. Use appropriate cutting fluid or lubricant when drilling steel to extend tool life and improve hole quality. Wear eye protection and follow applicable shop safety protocols when operating drilling equipment.