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JRJohnson
 
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Default Angle on bottom of special drill bit

Guys, I am making a drill bit that is 1 1/4" in diameter. This bit is for
drilling end grain wood on a wood lathe. That is, the drill bit will not
turn, but the wood does. Essentially the cutter is a piece of 5/8" wide
planer blade that is brazed to the end of a 1 1/4" tube. The trailing side
of the planer blade is ground away so the leading edge is in contact with
the wood. I want the drill bit to advance 1/8" per revolution. What is the
clearance angle I need too achieve this. That is, what angle should the
bottom of the cutter make with the axis of the bit? Incidentally, an air
tube ending just above the cutter takes the shaving out the top of the bit,
very similar to a rifle drill.

Gotta be someone on this group who can tell me the answer.

TIA,
James Johnson