Richard, Newton, etc, >Further I would ask what drilling speed of which drill bit >type is most suitable for Dilignit type blocks. Polished >bits, jobber bits, high spiral, low spiral and what speeds. This can be made as difficult, critical, expensive, and complicated as you care to make it. Heck, with a little work and creativity, you can probably even prove beyond a doubt that Man was never meant to be able to do something as impossibly demanding as drilling a suitable hole in a Delignit block. Might get you a statue in the park, or at least honorable mention in the Curmudgeons' Quarterly. Or, you could duck nearly all the potential problems up front by abandoning the assumption that the hole absolutely has to be drilled in one perfect pass, and go with the low tech, no fault, Uncle Wookie's idiot resistant block poking procedure. Double drill. The first pass is with a generic, anytypethatwillreachfromthechucktotheblock 1/4" or so drill bit. The rotational and feed speeds are determined by the following criteria: Does it smoke? Is the bit still turning? If the bit doesn't turn, your feed speed is too high. If it smokes, your rotational speed is too high. Any of the nearly infinite combinations of rotational speed and feed rates that makes a hole without smoking is dead-on the performance requirements. You're not fitting to the pin here, you're just making a hole. In tuners' terms, it's the finished hole's equivalent of a pitch raise - a pre-hole, or proto hole if you will. Any damage, trauma, passing offense, or hurt feelings the block incurs in the process will be reamed out with the second pass. It will get over it. The second pass is a tad more technically demanding in that you must actually HIT the previously drilled hole with the finish sized bit. This is rather important. Other than that, you can use a bit from the same anytypethatwillreachfromthechucktotheblock House of Bits product that you used to make the pre-hole. You can even use the same rotational speed, maybe slowing the feed speed a tad (another technical designation, a bit more than a smidgen) just for the appearance that it's difficult work and you're paying attention accordingly (in case someone's watching). There's a lot lower chance of smoke on the second pass, since the flutes of the drill aren't all clogged with chips, and the bit runs much cooler as a consequence. Done this way, it's very difficult to screw up drilling a Delignit block. It takes imagination, single minded dedication, and in extreme cases, a committee. I use 6.8mm for the final pass, or 17/64" if It's going someplace where the climate control is in the realm of mythology. >I have long lusted for a mortising tool thinking it could be >used for a number of things, like unbushing keys? > > Newton You'd take a mortising tool when you could have a biscuit joiner? Ron N
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