Cleveland C70129 Jobber Drill Bit 11mm Cobalt 135 Deg

Product Description

The CLEVELAND C70129 is a heavy-duty jobber length drill bit engineered for high-performance metal drilling in industrial and trade applications. Built from M42 cobalt high-speed steel, it delivers superior heat and wear resistance compared to standard HSS bits. The 135-degree split point reduces walking and cutting pressure at startup, eliminating the need for a center punch on most surfaces. A gold oxide coating provides additional lubricity and surface protection. At 5.59 inches overall length with a 3.70-inch spiral flute, this bit fits standard drill chucks and is suited for production drilling environments where precision and tool life matter.

The C70129 is intended for right-hand, spiral-flute drilling operations in aluminum and other non-ferrous and ferrous metals. The straight-cylindrical shank with a 0.4331-inch diameter seats securely in keyed or keyless chucks. Conforming to NAS 907 Type J standards, this bit is appropriate for aerospace, fabrication, MRO, and general machining applications where dimensional accuracy and consistent hole quality are required. The tapered web with web-thinning reduces thrust load and improves chip evacuation on through-holes.

Key Features

• M42 cobalt steel construction for extended tool life in abrasive and tough materials
• 135-degree split point reduces thrust and eliminates walking without center punching
• Gold oxide coating improves lubricity and resists heat buildup during drilling
• Web-thinned, tapered web reduces cutting force and improves chip flow
• Straight-cylindrical shank fits standard drill chucks without adapters
• Meets NAS 907 Type J specification for dimensional and performance compliance

Compatibility

Designed as an OEM-grade jobber length drill bit conforming to NAS 907 Type J standards, suitable for use in standard keyed or keyless drill chucks accepting a 0.4331-inch straight shank. Primary workpiece material is aluminum; also applicable to other metals within the 0.4000 to 0.5000 inch drill size range.

Installation Notes

Installation is performed by machinist or maintenance trades using a standard drill press, hand drill, or CNC spindle. Ensure the chuck and spindle are fully stopped before inserting or removing the bit. Apply appropriate cutting fluid for the workpiece material to extend tool life and improve surface finish. Inspect the cutting edges before each use and replace if chipping or wear is observed.