Chicago-Latrobe
Chicago-Latrobe 40586 135 Degree NAS-Type Aircraft Extension Drill 7/16 in
A 135-degree split-point aircraft extension drill bit in high-speed steel with black-oxide finish for 7/16 inch holes up to 1-3/4 inch depth
- TypeDrill Bits
- MaterialHAWA
- 135-degree split point starts holes cleanly without wandering
- High-speed steel with black oxide resists wear and corrosion
- 28-degree helix clears chips efficiently for deeper drilling
- 7/16 inch fractional size fits standard aerospace fasteners
- 4xD length reaches confined work areas on aircraft structures
Chicago-Latrobe 40586 Aircraft Extension Drill
This Chicago-Latrobe 40586 is a high-speed steel drill bit built for aircraft extension tasks. It features a 135-degree split point and black oxide finish for accurate starts and durability. The fractional inch bit measures 7/16 in with a maximum drilling depth of 1 3/4 in. It suits maintenance and fabrication jobs requiring extended reach.
For precision drilling in aviation and metalwork
Machinists and mechanics needing a 4xD reach with a self-centering point will find this bit suitable. The 28-degree helix angle supports efficient chip evacuation in deep holes. Buyers requiring carbide tips, coolant-through capability, or different point angles should look at other tooling options.
135-degree split point geometry
The 135-degree split point reduces walking and lowers thrust requirements when drilling high-performance alloys. This geometry is the primary factor determining suitability for hard materials and deep-hole accuracy. Verify the 7/16 in diameter and 1 3/4 in depth match your application requirements before purchase.
Highlights
- 135-degree split point starts holes cleanly without wandering
- High-speed steel with black oxide resists wear and corrosion
- 28-degree helix clears chips efficiently for deeper drilling
- 7/16 inch fractional size fits standard aerospace fasteners
- 4xD length reaches confined work areas on aircraft structures
Specifications
| Brand | CHICAGO-LATROBE |
|---|---|
| Type | Drill Bits |
| Material | HAWA |
Questions about this item
How deep can the 40586 drill bit bore before it hits its limit?
The bit is rated for a maximum drilling depth of 1 3/4 in, which is its 4xD design limit under sustained use.
Will the black-oxide high-speed steel bit run hot or draw excessive power during all-day drilling?
The 135-degree split point and HAWA-grade steel are engineered to reduce cutting force, keeping heat and power draw lower during extended operation.
What shank size must my drill chuck accept for this 7/16 in aircraft extension bit?
The bit uses a standard 7/16 in fractional shank, so your chuck must open to at least that diameter to hold it securely.
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