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Clearance and rake are rotated a lot on soft material drills - so that the rake is almost zero and the clearance is almost zero - that way the drill doesn't dig and the cut doesn't drive the drill in. This can be simulated with a stone - take the stone to a drill so that it's a right angles to the face and give it a few stokes along the line of the drill.
This will take the rake off at the tip and then stone the clearance off for a few strokes - that's the angle of the end of the drill that leaves the cutting edge clear of the shank.
Then use a high speed and no force to drill
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