> Well, I was thinking the other day while plunking >out a tuning for a rather mediocre upright that it might be a good idea >to pre drill the hole with a smaller size drill first. That's the way I do it. The first pass is with 1/4", and the second with 17/64, or 6.8mm. That's for Delignit, since the final hole is only about .013" undersize. For a maple block, the hole is considerably smaller and can be drilled in one pass. If you still want to do a two pass drill in the maple, do the pilot at about 7/32". With a two pass system, the type of drill becomes unimportant because chip clearing and bit heating aren't nearly as critical on that first pass, and no problem at all on the second, since you're just doing a final ream to size. I use regular jobbers bits. It is more time consuming, but it's also more idiot resistant, and produces more uniform results - both of which appeal to me since I'm the idiot doing the work and taking the blame after the dust settles. Ron N
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