> 1st pass, drill hole @ 1/4" using a fixture I made which holds a 1/4" drill > bushing right up close and personal > to the block to stabilize the initial hole and make up for the inaccuracy of my > press. I transfer punch and center drill mine for the same reason. > 2nd pass with a slightly shy "I" bit (.271) which has a non-cutting 1/4" pilot > ground on the 1st 1/2" > of the tip to center the 2nd pass. The ground down section is not really necessary. The second pass will center nicely in the pilot hole automatically. I suspect, in fact, that an old worn out sloppy press like my own aids this self centering, if anything. Then again, have you tried test drilling some Delignit scrap in a single pass with this step drill? >I dust the pins with rosin before driving. Likewise. > Holes are nice and consistent as proved by consistent torques (130in/lb) on .282 > mic'd pins. > > Here's the weird part. I mic the pins and am mostly only using the pins that are > either .282, or slightly light > at about .281 or .2805. When I drive both the .282 and the light pins the light > pins consistently torque at > about 20-25 lbs more than the .282 pins. What pins are you using, that you get that much variation? > This makes absolutely no sense to me. > > Any ideas why this is happening? None whatsoever, but I'd happily smile and take it as if I'd done something to earn it. I used to drill the second pass in Delignit with a 6.8mm (0.268"), and before that, a 1/4" single pass in the maple multilam. Since I started using the 9mm Delignit capped maple multilam composite, I get higher final torque with the 6.8mm second pass than I did with Delignit. The bit mic's the same, so it's not wearing down smaller, otherwise I don't know why that is. Ron N
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