Chicago-Latrobe
Chicago-Latrobe 47727 27/64 in 135 Degree Cobalt Drill Bit
Cobalt jobber-length drill bit with 135-degree split point for hard-metal drilling
- TypeDrill Bits
- MaterialHAWA
- 135-degree split point starts on contact without walking
- Cobalt steel resists heat and wear in hard metals
- 27/64 inch fractional size matches common tap charts
- Jobber length gives standard reach for general drilling
- Straw bronze finish reduces friction and aids chip flow
Chicago-Latrobe 47727 Cobalt Jobber Bit
The Chicago-Latrobe 47727 is a jobber length drill bit made from cobalt steel with a 135 degree split point. It has a fractional size of 27/64 inch and a decimal equivalent of .4219. The bit features a straw bronze finish and no coolant holes. It is designed for heavy-duty drilling tasks.
Suited for hard materials and precision starts
This bit suits machinists and maintenance technicians who need a self-centering split point for drilling stainless steel or other tough alloys. The cobalt construction resists heat during extended use. Buyers who require a coolant-through design for deep-hole chip evacuation should look at alternative tooling. Those needing a different fractional diameter must select another size.
135 degree split point geometry
The 135 degree split point is the specification that determines suitability. It reduces walking on hard surfaces and lowers thrust requirements compared to standard points. This geometry is essential for effective drilling in work-hardening materials. Confirm the point angle matches the application before purchase.
Highlights
- 135-degree split point starts on contact without walking
- Cobalt steel resists heat and wear in hard metals
- 27/64 inch fractional size matches common tap charts
- Jobber length gives standard reach for general drilling
- Straw bronze finish reduces friction and aids chip flow
Specifications
| Brand | CHICAGO-LATROBE |
|---|---|
| Type | Drill Bits |
| Material | HAWA |
Questions about this item
Does the 27/64 in cobalt drill bit come alone or in a set, and do I need a separate chuck?
The 47727 is a single jobber-length bit with a 135-degree split point; it fits any standard 1/2 in or larger drill chuck, so no extra chuck is required.
When should I choose the 27/64 in size instead of a smaller or larger fractional bit?
Choose the 27/64 in (0.4219 decimal) when the hole must match that exact fractional diameter for bolt clearance, tap sizing, or reaming operations in tough metals.
How does the 135-degree split point perform once the bit is in a hand drill or press?
The 135-degree split point self-centres on contact, reduces thrust, and cuts cleanly through hard steel and stainless without walking, even without coolant.
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