Cleveland C15931 Cobalt Jobber Drill Bit 11/64 in

Product Description

The CLEVELAND C15931 is a cobalt jobber length drill bit designed for demanding metal drilling applications. Built from M42 high-cobalt steel and finished with an oxide coating, this bit delivers the heat resistance and edge retention required when drilling superalloys, stainless steel, and other hard materials. The 135-degree split point reduces walking on contact and allows drilling without a center punch in most applications. With a 3-1/4 inch overall length and 11/64 inch diameter, this is a standard jobber form factor suited for use in drill presses, CNC machines, and hand-held power drills across maintenance, fabrication, and mechanical contracting work.

This drill bit is rated for superalloy and hard-material workpieces, making it a go-to choice for HVAC technicians, pipefitters, millwrights, and general trade professionals who regularly drill into hardened or exotic metals. The fast spiral flute promotes efficient chip evacuation during deep-hole drilling, and the straight-cylindrical shank seats securely in standard 3-jaw chucks. It conforms to ASME B94.11M standards and carries an NAS specification designation, meeting the dimensional and performance requirements expected of heavy-duty tooling in professional shop and field environments.

Key Features

• M42 cobalt steel construction for superior heat and wear resistance in hard-material drilling
• 135-degree split point reduces thrust force and eliminates walking without a center punch
• Oxide coating provides lubricity and additional corrosion resistance
• Fast spiral flute with web-thinned, tapered web geometry for efficient chip removal
• Straight-cylindrical shank fits standard 3-jaw drill chucks
• Meets ASME B94.11M and NAS specification requirements for heavy-duty jobber drills

Compatibility

Designed for drilling superalloys and other hard workpiece materials; compatible with any drill press, machining center, or handheld power drill accepting an 11/64 inch straight-cylindrical shank. Fits Series 3780 application requirements per manufacturer designation.

Installation Notes

Installation and use should be performed by qualified machinists, tool-and-die workers, or experienced trade professionals familiar with metal-cutting operations. Secure the shank fully in the chuck and verify concentricity before drilling. Use appropriate cutting fluid or coolant to extend bit life when drilling superalloys or stainless steel, as this bit does not support through-coolant. Disconnect and de-energize all equipment before changing bits, and follow applicable OSHA and shop safety protocols for rotating machinery.