Rich, I've always use a "rule of thumb", that if the pinblock is 1 1/4", I use 2 1/4" tuning pins. It leaves the tuning pins just shy of the bottom of the pin block, (that is if the web is not excessively thick). As I do not drill all the way through my pinblocks, but simply "dimple" them, like we do for upright hammers. This dimple is to relieve the hydrolic pressure of the Pin Driving fluid. As I firmly believe that a completely sealed pinblock will last longer, this is how I do it. (99% of the pinblocks I've had to replace were drilled all the way through.) Best Regards, Joe Garrett, RPT, (Oregon) Been There, Didn't Like It, So I'm Here To Stay! [G}
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