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Drill America cobalt aircraft extension drill bit size 6 12in overall length 2-1/2 flute length .2040 decimal equivalent heavy duty

Drill America

Drill America Cobalt Aircraft Extension Drill Bit #6 12in

SKU CH-AF5R-QX8V6

A 12 inch cobalt aircraft extension drill bit with a heavy-duty split point for precision drilling

  • Product typeDrill Accessories
  • Extended reach for deep holes with 12 inch overall length
  • Cobalt steel resists heat and wear during heavy-duty drilling
  • Split-point tip starts on contact without walking
  • Decimal size .2040 matches #6 specification for precise fit

Cobalt Aircraft Extension Drill Bit #6 12in

This cobalt steel drill bit is built for heavy-duty drilling tasks requiring extended reach. Its split-point design helps reduce walking and improves starting accuracy on metal surfaces. The 12-inch overall length suits aircraft maintenance and deep-hole applications where standard bits cannot reach. It is intended for professional mechanics and fabricators working with tough alloys.

Heat resistance and cutting efficiency

Cobalt steel construction maintains hardness at higher temperatures generated during prolonged drilling. The split-point geometry reduces thrust force, lowering power draw and vibration during operation. Efficient chip evacuation through the flutes minimises friction and heat buildup in the hole. These characteristics support consistent performance in demanding metalworking environments.

How it compares

Measured against everything we stock in Bits, Hole Saws & Accessory Kits, at today’s prices. Recalculated every night.

Price $9.99
Cheaper than about 88% of the 5,493 comparable items (median $27.99).

Specifications

Product
Brand nameDrill America
Product typeDrill Accessories

Questions about this item

How do I fit the 12in aircraft extension bit into my drill chuck?

Insert the straight shank fully into the chuck and tighten all three jaws evenly; the common mistake is clamping only on the flute area, which lets the bit walk under load.

When should I replace the #6 cobalt split-point bit?

Replace it once the split point rounds over or the 2-1/2in flute length wears shorter, because a dull cobalt tip work-hardens the hole and cannot be reliably resharpened.

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