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Pablo
 
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Default drilling 'actual' sized holes with HSS drill bits

An old toolmaker's method is to pre-drill .010" - .015" undersize then rub
the sharp corners off the outer edges of the finish drill before drilling at
a reduced speed, high feed rate & a little oil. I have used this method for
many years mostly for fitting dowell pins. I have never needed a reamer to
do this.

Paul Cordell, Nth. Qld. Australia.