Hertel 74131921 Cobalt Drill Bit Letter S 0.3480 in

Product Description

The HERTEL 74131921 is a cobalt screw machine length drill bit designed for high-performance drilling in tough materials. Built to letter size S, the bit cuts a 0.3480-inch diameter hole and features a 135-degree split point that reduces walking and allows for faster penetration without a center punch. A TiAlN coating increases surface hardness and heat resistance, extending tool life in demanding production and maintenance environments. The shorter-than-standard screw machine length provides added rigidity, making this bit a practical choice for use in drill presses, lathes, and CNC machines where chatter and deflection need to be minimized.

This bit is suited for drilling steel, stainless steel, cast iron, and other hard ferrous and non-ferrous metals in both production shop and field maintenance settings. The straight cylindrical shank fits standard drill chucks without adapters. The right-hand spiral flute efficiently evacuates chips during through-hole and blind-hole drilling. Machinists, tool-and-die workers, and maintenance mechanics working in industrial or commercial environments are the typical end users for this type of tooling.

Key Features

• Letter S size cutting diameter of 0.3480 inches for precise hole sizing
• 135-degree split point reduces thrust and eliminates walk on entry
• TiAlN coating improves heat resistance and extends tool life in hard materials
• Cobalt construction maintains hardness at elevated cutting temperatures
• Web-thinned parallel web reduces cutting resistance and improves chip flow
• Screw machine length overall provides extra rigidity versus jobber-length bits

Compatibility

Designed as an OEM-style replacement or direct-use screw machine drill bit compatible with any standard drill chuck accepting a straight cylindrical shank in the 0.3000 to 0.3500 inch diameter range.

Installation Notes

This bit is installed and replaced by machinists or maintenance mechanics using standard drill chuck tooling. Ensure the machine spindle is fully stopped and locked out before changing bits. Verify chuck jaw condition and confirm the shank is fully seated and tightened before operation. Follow applicable shop safety standards and machine manufacturer guidelines for feed rate and cutting speed when drilling hard metals with cobalt tooling.