Bordo Cobalt Jobber Drill Refill Set
135° Split Point (crankshaft point)
Split point is self centering and the short distance from the drill axis to the outer corners results in faster penetration, reducing the need for end thrust. The 135º point should be used to cut harder steel materials especially in deep hole applications. In these situations it will produce thicker chips minimizing work hardening of the cavity. Faster penetration reduces abrasion and friction along the cutting edges. Cobalt HSS jobber drills are extremely hard and provide superior performance and increased tool life especially in stainless steel and high tensile steel.
DRILL BIT SURFACE TREATMENT
Bronze Finish (gold oxide). The metallic brown coloured low temperature temper treatment is normally only used on cobalt tools for identification purposes.
1.0-6.5mm x 0.5mm increments