Cleveland C70154 Jobber Drill Bit Size 21 Cobalt

Product Description

The CLEVELAND C70154 is a cobalt jobber-length drill bit in wire gauge size 21 (0.1590 inches), designed for heavy-duty drilling in metalworking applications. Manufactured from M42 cobalt high-speed steel with a gold oxide coating, this bit handles elevated heat and wear better than standard HSS tooling. The 135-degree split point starts on contact without a center punch and reduces walking on smooth surfaces. Overall length is 3.25 inches with a 2.125-inch spiral flute and a straight cylindrical shank. Right-hand cut with a regular spiral and tapered web configuration, this bit is built for production and maintenance drilling where tool life and hole quality matter.

The C70154 is suited for drilling aluminum and other non-ferrous metals, as well as mild steel and stainless applications where cobalt tooling is specified. The gold oxide finish reduces friction and helps extend tool life in repetitive drilling cycles. At wire size 21 with a 0.1590-inch diameter, this bit fits common tapping and clearance hole applications in sheet metal, structural work, and mechanical assembly. It meets NAS 907 Type J standards, making it appropriate for aerospace and precision industrial environments. Sold individually, it works in standard drill chucks and drill press setups.

Key Features

• M42 cobalt steel construction handles heat and abrasion in demanding drilling applications
• 135-degree split point reduces thrust and eliminates center-punch requirement on most surfaces
• Gold oxide coating lowers friction and extends tool life in repetitive use
• Web-thinned, tapered web configuration improves chip evacuation and cutting efficiency
• Meets NAS 907 Type J specification for aerospace and precision industrial use
• Right-hand cut, regular spiral flute with straight cylindrical shank fits standard chucks

Compatibility

Designed as an OEM-style replacement and standard-use cobalt jobber drill bit for metalworking applications requiring wire gauge size 21 (0.1590 inches) diameter and NAS 907 Type J compliance.

Installation Notes

Drill bits of this type are installed by machinists, maintenance technicians, and sheet metal workers using standard keyed or keyless drill chucks. Secure the shank fully in the chuck before use and verify chuck runout is within acceptable limits to maintain hole tolerance. Use appropriate cutting fluid for the workpiece material to maximize tool life. Inspect the cutting edges before each use and replace if chipping or dulling is observed.