Hertel 42154 Cobalt Jobber Drill 5/16 Inch 135 Degree

Product Description

The HERTEL 42154 is a cobalt jobber-length drill bit designed for cutting through stainless steel, hardened materials, and other tough alloys that wear down standard high-speed steel tooling. Built from M35 cobalt steel, it runs a 5/16-inch diameter with a 135-degree split point that self-centers on contact, reducing the need for a center punch and minimizing walking on hard surfaces. The right-hand spiral flute geometry promotes chip evacuation during through-hole drilling. This is a heavy-duty production tool suited for machinists, maintenance technicians, fabricators, and trade professionals who drill into corrosion-resistant or work-hardened base metals regularly.

This drill bit is built for use on stainless steel and hardened materials in both shop and field environments. Its 3-3/16-inch flute length handles standard jobber-depth holes, and the straight cylindrical shank seats in any standard drill chuck or drill press spindle. The 4-1/2-inch overall length fits benchtop drill presses, hand drills, and CNC drilling operations. The straw oxide finish provides a visual indicator of heat treatment without adding a slick coating that could mask wear. Typical applications include metal fabrication, HVAC equipment manufacturing, plumbing rough-in through metal studs, and electrical panel work requiring clean holes in stainless enclosures.

Key Features

• M35 cobalt steel construction for drilling stainless steel and hardened materials
• 135-degree split point self-centers and reduces thrust force on hard surfaces
• Right-hand regular spiral flute promotes efficient chip clearing
• 3-3/16-inch flute length with 5xD flute-to-diameter ratio for jobber-depth holes
• Straight cylindrical shank fits standard drill chucks and drill press spindles
• Straw oxide finish is coolant-free rated — no through-coolant required

Compatibility

Designed as a jobber-length replacement drill bit for use in standard 3-jaw drill chucks and drill press spindles accepting a straight cylindrical shank. Optimized for drilling stainless steel and hardened materials.

Installation Notes

This drill bit is installed by trade professionals and machinists in drill presses, hand drills, or CNC equipment with a compatible chuck. Secure the straight shank firmly in the chuck before operation and verify that drill speed is appropriate for the workpiece material and bit diameter — cobalt bits in stainless steel typically require slower RPM and steady feed pressure to prevent work hardening. Always wear appropriate eye protection and secure the workpiece before drilling. Inspect the cutting edges before each use and replace the bit if chipping or dulling is visible.