Chicago-Latrobe
Chicago-Latrobe 11154 #30 135 Degree NAS Aircraft Extension Drill
A #30 high-speed steel aircraft extension drill with a 135-degree split point and black oxide finish for deep-hole drilling
- Precise hole starts with 135-degree split point
- #30 wire gauge suits aircraft extension drilling
- 1-5/8 in max depth handles deep holes
- High-speed steel with black oxide resists wear
- 28-degree helix improves chip evacuation
Chicago-Latrobe 11154 #30 Aircraft Extension Drill
This Chicago-Latrobe 11154 drill bit is a #30 size extension drill designed for aircraft applications. It suits maintenance technicians and metalworkers who need extended reach in confined structural areas. The high-speed steel construction with black oxide finish provides durability for repetitive drilling tasks in demanding environments.
135-degree split point with 28-degree helix angle
The 135-degree split point reduces walking and lowers thrust requirements when starting holes in hard materials. A 28-degree helix angle manages chip evacuation in deep holes up to 1 5/8 inches maximum drilling depth. The 4xD length-to-diameter ratio defines the practical reach limit for this wire-gauge tool in typical aviation alloys.
Straightforward chuck installation
The straight shank fits standard drill chucks without adapters or specialised tooling. Extension length increases run-out risk, so operators should use steady pressure and proper alignment to prevent bit breakage. Black oxide coating can wear under high-speed misuse, reducing lubricity and increasing heat buildup during prolonged cycles.
Highlights
- Precise hole starts with 135-degree split point
- #30 wire gauge suits aircraft extension drilling
- 1-5/8 in max depth handles deep holes
- High-speed steel with black oxide resists wear
- 28-degree helix improves chip evacuation
Specifications
| Brand | CHICAGO-LATROBE |
|---|
Questions about this item
What does the #30 size mean for this aircraft extension drill?
The #30 wire gauge size indicates a specific diameter suited for precision drilling in aviation applications.
How does the 135-degree split point perform in a drill press or hand drill?
The 135-degree split point is designed to start on contact and reduce walking in tough materials like stainless steel or titanium.
What does the 28-degree specification refer to on this high-speed steel bit?
The 28-degree figure relates to the helix angle, which affects chip evacuation and cutting efficiency in deep-hole drilling.
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