Hertel 74131103 Cobalt Screw Machine Drill Bit Size 58

Product Description

The HERTEL 74131103 is a cobalt screw machine length drill bit designed for high-speed drilling in tough materials including stainless steel, alloy steel, and other hard metals. Built to the HSCO135 series standard, it features a 135-degree split point that reduces walking on contact and requires no center punch in most applications. The bit measures 1.375 inches overall length with a 0.5 inch flute length, making it compact and rigid for short-reach drilling operations. The straight cylindrical shank fits standard drill chucks. Web thinning with a parallel web configuration reduces thrust and improves chip evacuation. Machinists, toolroom technicians, and maintenance mechanics are the typical end users for this type of bit.

This bit is sized at wire gauge 58, equivalent to 0.0420 inch decimal diameter. It is suited for precision drilling in CNC machining centers, drill presses, and hand-held power tools where a short, stiff drill is preferred over jobber-length alternatives. The screw machine length format reduces deflection and improves hole location accuracy in close-tolerance work. Typical applications include tapping prep holes, clearance holes in sheet metal and structural components, and fixture work in fabrication or maintenance environments.

Key Features

• Cobalt construction provides heat resistance and durability in hard and abrasive materials
• 135-degree split point reduces thrust and eliminates walking without a center punch
• Screw machine length at 1.375 inches overall increases rigidity and reduces deflection versus jobber-length bits
• Web-thinned parallel web design lowers cutting resistance and improves chip flow
• Right-hand cutting, regular spiral flute pattern for standard clockwise drill operation
• Straight cylindrical shank fits standard 3-jaw chucks and collet holders

Compatibility

Designed as a direct-fit replacement for wire gauge size 58 screw machine length drill bits in standard straight-shank chuck configurations. Verify spindle speed and feed rate compatibility with the workpiece material before use.

Installation Notes

Installation of this bit is performed by machinists and maintenance technicians using a keyed or keyless drill chuck sized for a straight shank. Ensure the drill press or machining center is powered down and locked out before changing tooling. Secure the shank fully in the chuck to the full depth of the jaws to prevent slippage during operation. Do not exceed the recommended spindle speed for the workpiece material and bit diameter.