Chicago-Latrobe 54117 135° Cobalt Jobber Drill Bit R .3390 TiN

Chicago-Latrobe 54117 Cobalt Jobber Drill Bit R

The Chicago-Latrobe 54117 is a new heavy-duty jobber length drill bit made from cobalt steel with a titanium nitride coating. It features a 135-degree split point designed for self-centering and reduced thrust. The bit handles letter size R with a decimal equivalent of .3390 for precise hole making.

Machinists drilling hardened steel

This bit suits machinists and maintenance technicians who need a durable cutter for tough alloys where a standard point would walk or wear quickly. The cobalt substrate and TiN finish resist heat and abrasion in demanding materials. Buyers who only drill wood, plastic or soft aluminium will not benefit from the added cost and hardness of this construction.

135-degree split point geometry

The 135-degree split point is the specification that decides if this bit matches the application because it centres without a pilot hole and lowers the feed pressure required in hard metals. A different point angle would not provide the same self-centering action or chip evacuation in these conditions. No other specification overrides this geometry for the intended difficult drilling tasks.