Chicago-Latrobe
Chicago-Latrobe 47721 135° Cobalt Jobber Drill Bit 21/64 in
A 21/64-inch cobalt jobber drill bit with a 135-degree split point for hard-metal drilling
- TypeDrill Bits
- MaterialHAWA
- Cobalt steel resists heat and wear
- 135-degree split point starts holes without wandering
- Jobber length reaches standard drilling depths
- 21/64 inch diameter matches fractional specifications
- Decimal equivalent .3281 ensures precise sizing
Chicago-Latrobe 47721 21/64 in Cobalt Drill Bit
This Chicago-Latrobe 47721 is a jobber-length drill bit made from cobalt steel for drilling hard metals. It has a 21/64 inch diameter with a decimal equivalent of 0.3281 inches. The 135-degree split point design helps reduce walking and starts holes cleanly. It suits mechanics and fabricators who need a durable bit for stainless steel or high-tensile alloys.
Check your chuck capacity
Verify that your drill chuck accepts a 21/64 inch shank diameter. Confirm the workpiece material matches cobalt capabilities such as stainless steel, cast iron or titanium. This bit has no coolant holes so external lubrication is required for deep holes. Ensure your drill delivers enough torque for the larger diameter without stalling.
Suits metalworkers drilling tough alloys.
This bit suits professionals drilling high-hardness metals where standard high-speed steel wears too fast. It is not for woodworkers or plastics fabricators because the aggressive split point can grab and tear softer materials. Buyers who need coolant-through capability for deep-hole production should look at a different design. Hobbyists doing occasional light work may find a standard bit more economical.
Highlights
- Cobalt steel resists heat and wear
- 135-degree split point starts holes without wandering
- Jobber length reaches standard drilling depths
- 21/64 inch diameter matches fractional specifications
- Decimal equivalent .3281 ensures precise sizing
Specifications
| Brand | CHICAGO-LATROBE |
|---|---|
| Type | Drill Bits |
| Material | HAWA |
Questions about this item
What comes in the box with the Chicago-Latrobe 47721 21/64 in cobalt drill bit and do I need to buy anything else to use it?
The box contains the single 135° split-point cobalt jobber bit; no extra accessories are included, so you only need a drill chuck that accepts a 0.3281 in shank.
The listing shows only the 21/64 in size — how do I know if this is the right diameter for my job?
Choose this bit when the hole must be exactly 21/64 in (0.3281 in); if your drawing or tap chart calls for a different fractional size, select that size instead.
What does the 135° split point actually do when the bit is in a drill press or hand drill?
The 135° split point centres itself on contact, cuts with less pressure, and works well in hard materials such as stainless steel or titanium alloys.
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