Drill America
Drill America 1-1/8in Reduced Shank Cobalt Silver and Deming Drill Bit
A cobalt steel drill bit with a reduced 1/2 inch shank and 1.1250 inch cutting diameter for large-hole drilling in tough metals
- TypeDrill Accessories
- 1-1/8in diameter drills large holes
- Cobalt steel resists heat in hard metals
- Bronze oxide finish reduces friction and wear
- 1/2in reduced shank fits standard chucks
1-1/8in Cobalt Drill Bit with Reduced Shank
This cobalt steel drill bit features a 1/2in reduced shank that fits standard drill chucks while delivering a 1-1/8in cutting diameter. The bronze oxide surface treatment reduces friction and resists corrosion during heavy-duty metal drilling. Decimal equivalent is 1.1250 for precise hole sizing. Designed for machinists and maintenance professionals who need large-diameter holes in tough alloys.
Heat dissipation and power characteristics
Cobalt steel construction maintains hardness at elevated temperatures generated when drilling stainless steel and high-strength materials. The surface-treated flutes improve chip evacuation, lowering cutting resistance and motor load during extended operations. Reduced shank design minimises vibration transfer to the drill motor, helping control noise levels in workshop environments. Overall length of 6in and flute length of 3in provide reach without excessive deflection.
Highlights
- 1-1/8in diameter drills large holes
- Cobalt steel resists heat in hard metals
- Bronze oxide finish reduces friction and wear
- 1/2in reduced shank fits standard chucks
Specifications
| Brand | Drill America |
|---|---|
| Type | Drill Accessories |
Questions about this item
How do I install the 1/2in reduced shank on this 1-1/8in cobalt drill bit?
Insert the reduced shank fully into a 1/2in chuck and tighten securely; the step often missed is not seating the shank completely, which can cause run-out on the 1.1250in cutting diameter.
What maintenance will this cobalt silver and deming drill bit need later?
Resharpen the cobalt steel cutting edges when they dull; the bronze oxide surface treatment on the 3in flutes helps chip evacuation but wears off with heavy use.
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