Drill America
Drill America 7/8in 1/2in Reduced Shank Cobalt Silver and Deming Drill Bit pneumatic accessory
7/8-inch cobalt drill bit with a 1/2-inch reduced shank for heavy-duty drilling
- TypeDrill Accessories
- Cobalt steel resists heat in tough materials
- Reduced 1/2in shank fits standard chucks
- Bronze oxide finish adds corrosion protection
- 8750 decimal equivalent for precise hole sizing
Reduced Shank Cobalt Drill Bit
This 7/8 inch cobalt steel drill bit features a reduced shank that fits a standard 1/2 inch chuck. It is built for drilling tough materials where high-speed steel would wear quickly. The bronze oxide finish helps reduce friction and resist heat during heavy cutting. It suits mechanics and fabricators who need a single large-diameter bit without a specialised holder.
Practical Limits of Reduced Shank Bits
The reduced shank concentrates torque on a smaller neck, so excessive feed pressure can snap the bit or spin it in the chuck. Cobalt steel is brittle compared to high-speed steel and chips if the workpiece moves or the spindle runs out of true. Flute length limits hole depth to the effective cutting reach. The design is not intended for deep-hole production drilling or CNC rigidity.
Highlights
- Cobalt steel resists heat in tough materials
- Reduced 1/2in shank fits standard chucks
- Bronze oxide finish adds corrosion protection
- 8750 decimal equivalent for precise hole sizing
Specifications
| Brand | Drill America |
|---|---|
| Type | Drill Accessories |
Questions about this item
Should I choose the 7/8 inch cobalt bit with a 1/2 inch reduced shank for my 1/2 inch chuck?
Yes, the 1/2 inch reduced shank fits a standard 1/2 inch drill chuck while the 7/8 inch cutting diameter handles larger holes.
What does the .8750 decimal equivalent mean when drilling?
The .8750 figure is the exact cutting diameter in inches, so the bit produces a 7/8 inch hole in metal, wood or plastic.
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