Hertel 74131079 Cobalt Screw Machine Drill Bit Size 55

Product Description

The HERTEL 74131079 is a cobalt screw machine length drill bit designed for high-speed drilling in tough materials including stainless steel, hardened alloys, and heat-resistant metals. The bit measures 0.0520 inches in diameter (wire size 55) with an overall length of 1.625 inches and a flute length of 0.625 inches. The 135-degree split point reduces walking and requires no center punch on most surfaces. A web-thinned, parallel web configuration improves chip clearance and lowers thrust during entry. Right-hand cutting with a regular spiral flute makes this a standard choice for machinists and metalworkers drilling small-diameter holes in production and job shop environments.

This drill bit fits screw machine length applications where a shorter, stiffer tool is preferred over jobber length for improved rigidity and hole accuracy. The cobalt construction handles elevated cutting temperatures without losing hardness, making it well suited for stainless steel, titanium, and other work-hardening materials. It is used in CNC machining centers, drill presses, and hand-held power tools wherever a small-diameter, short-length bit is needed. The straight cylindrical shank seats in standard drill chucks without adapters. Sold individually with a minimum order quantity of 12 units.

Key Features

• Wire size 55, 0.0520-inch diameter for small-hole precision work
• 135-degree split point reduces thrust and eliminates walking without center punching
• Cobalt construction retains hardness at elevated cutting temperatures
• Web-thinned parallel web improves chip evacuation and lowers feed force
• Screw machine length (1.625 inches OAL) provides added rigidity over jobber length bits
• Right-hand cut, regular spiral flute, straight shank fits standard chucks

Compatibility

Designed for use in standard drill chucks accepting straight cylindrical shanks. Fits within the HERTEL HSCO135 series and suits drilling applications in the 0.0000 to 0.1000 inch diameter range.

Installation Notes

Installation is performed by machinists or metalworking tradespeople using a drill press, milling machine, or CNC machining center with a suitable chuck. Secure the shank fully in the chuck before operation and verify runout before drilling into finished workpieces. Cobalt bits can be run at higher surface speeds than standard HSS, but feed rates must be appropriate for the material to avoid tip breakage at this small diameter. Coolant or cutting oil is recommended where the setup permits, even though coolant-through is not available on this bit.