Chicago-Latrobe 46486 135° Cobalt Jobber Drill Bit 9 mm

9 mm Cobalt Jobber Drill Bit

This 9 mm cobalt jobber drill bit is designed for drilling into hard metals such as stainless steel and high-strength alloys. The 135-degree split point reduces walking and starts holes accurately without a centre punch. It suits professional mechanics, metal fabricators and maintenance technicians who need reliable performance in tough materials.

Upgrade from standard high-speed steel bits

Standard high-speed steel bits wear quickly in abrasive or work-hardening metals, leading to frequent changes and poor hole quality. Switching to this cobalt bit is worth it when drilling stainless steel, titanium or hardened steel where heat resistance and edge retention matter. The straw-bronze surface indicates the cobalt alloy composition that maintains hardness at higher temperatures.

Sustained drilling in hard metals

Under continuous use the cobalt substrate resists softening better than conventional steel, keeping the cutting edges sharp for longer. The split-point geometry reduces thrust force, which lowers heat build-up during extended drilling cycles. With no coolant holes the bit relies on external lubrication or peck drilling to manage chips and temperature in deep holes.