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Drill America

Drill America 31/64in Cobalt Reduced Shank Drill Bit x 3/8 Shank pneumatic accessory

SKU CH-7WKM-X3BDX

A 31/64 inch cobalt drill bit with a reduced 3/8 inch shank for drilling hard metals

  • TypeDrill Accessories
  • 31/64 inch cobalt steel resists heat and wear
  • Reduced 3/8 shank fits standard drill chucks
  • Bronze oxide finish lowers friction during drilling
  • 4-3/8 flute length clears chips from deep holes

31/64in Cobalt Reduced Shank Drill Bit

This 31/64 inch cobalt drill bit features a reduced shank that fits a 3/8 inch chuck. It is built from cobalt steel with bronze oxide surface-treated flutes for drilling hard metals. The decimal equivalent is .4844 inch with a flute length of 4-3/8 inch and overall length of 5-7/8 inch.

Reduced Shank Limits Chuck Compatibility

The reduced shank design allows use in 3/8 inch chucks but cannot be secured in smaller chucks. Cobalt steel resists heat yet remains brittle under heavy side loads or interrupted cuts. The fixed 31/64 inch diameter prevents drilling larger or smaller holes without changing bits. Bronze oxide coating wears over time and does not replace cutting fluid.

Highlights

  • 31/64 inch cobalt steel resists heat and wear
  • Reduced 3/8 shank fits standard drill chucks
  • Bronze oxide finish lowers friction during drilling
  • 4-3/8 flute length clears chips from deep holes

Specifications

BrandDrill America
TypeDrill Accessories

Questions about this item

Should I choose the 31/64 inch cobalt bit or a different size for my 3/8 inch chuck?

This bit has a 31/64 inch cutting diameter and a reduced 3/8 inch shank designed to fit your chuck, so choose this size when you need that exact hole diameter.

What does the .4844 decimal equivalent mean for drilling accuracy in my machine?

The .4844 decimal equivalent is the precise diameter of the cobalt steel bit, ensuring the hole matches the specification when the drill runs true in your pneumatic tool.

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