Chicago-Latrobe
Chicago-Latrobe 54117 135° Cobalt Jobber Drill Bit R .3390 TiN
Cobalt jobber-length drill bit with 135° split point and TiN coating drills hard metals at .3390 inch diameter
- TypeDrill Bits
- 135° split point reduces walking on hard steel
- Cobalt alloy holds edge longer in high-heat drilling
- TiN coating lowers friction and extends bit life
- Jobber length fits standard chucks for versatile use
- Decimal size .3390 matches letter R for precise holes
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.
Highlights
- 135° split point reduces walking on hard steel
- Cobalt alloy holds edge longer in high-heat drilling
- TiN coating lowers friction and extends bit life
- Jobber length fits standard chucks for versatile use
- Decimal size .3390 matches letter R for precise holes
Specifications
| Brand | CHICAGO-LATROBE |
|---|---|
| Type | Drill Bits |
Questions about this item
What does the 135-degree split point do in a real machine?
The 135-degree split point is designed to start holes accurately without wandering, especially in harder materials where a standard point might slip.
How does the TiN coating affect drilling performance?
The titanium nitride coating increases surface hardness and reduces friction, helping the bit run cooler and last longer when cutting tough alloys.
What does the .3390 decimal equivalent tell me about fit?
The .3390-inch diameter corresponds to letter size R, so it fits standard drill chucks and matches tap drill charts for that specific fractional size.
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