Cleveland C16633 Jobber Drill Bit Size 21 Cobalt 135deg

Product Description

The CLEVELAND C16633 is a jobber-length twist drill bit designed for demanding metal drilling applications. Built from M42 cobalt high-speed steel and finished with a titanium nitride (TiN) coating, it delivers extended tool life and improved heat resistance compared to standard HSS bits. The 135-degree split point starts on contact without center-punching and reduces walking on hard or uneven surfaces. A parabolic flute geometry improves chip evacuation in deep-hole drilling. The overall length is 3.5 inches with a straight-cylindrical shank at 0.159 inches in diameter. This bit is installed by machinists, tool-and-die trades, pipefitters, and HVAC-plumbing fabricators working with stainless, hardened steel, and other tough alloys.

The C16633 cuts a 0.159-inch diameter hole, corresponding to wire gauge size 21. The parabolic flute and web-thinned, tapered web construction reduce thrust and make this bit well suited for production drilling in ferrous metals, stainless steel, and high-nickel alloys where standard cobalt bits tend to overheat or wear prematurely. It is packaged as a single unit and is a common choice for maintenance shops, fabrication floors, and field service technicians who need a reliable heavy-duty bit without buying a full set.

Key Features

• M42 cobalt steel construction for heavy-duty drilling in hard and abrasive metals
• Titanium nitride (TiN) coating extends tool life and reduces friction heat
• 135-degree split point for self-centering start and reduced drill walking
• Parabolic flute geometry for efficient chip evacuation in deep holes
• Web-thinned, tapered web reduces cutting thrust
• Straight-cylindrical shank compatible with standard drill chucks
• Meets ASME B94.11M and DIN 338 standards

Compatibility

Designed as an OEM-style replacement or direct-procurement jobber drill bit for standard three-jaw drill chucks accepting a 0.159-inch straight-cylindrical shank, consistent with Series 2075T heavy-duty cobalt jobber-length bits.

Installation Notes

Secure the straight-cylindrical shank firmly in a keyed or keyless drill chuck before operation, and verify chuck runout is within acceptable tolerance to protect bit geometry. Power down and de-energize the drill press or hand drill before changing bits. Use appropriate cutting fluid when drilling stainless steel or high-nickel alloys to manage heat buildup. Follow applicable shop safety standards and wear eye protection during all drilling operations.