John Formsma asked: "My first separated vertical pinblock repair job is coming up soon. I think know the basic concept of what to do. Is it: drop tension slightly, drill, position bolts/washers/nuts, glue, clamp by tightening bolts, let glue dry, tune? Need advice on some specifics. Is there a specific type of drill bit that is good for this? Or would any correctly sized metal bit that's long enough to go through the piano work? (I'm woefully ignorant of drill bit types, although I know to go slowly during metal drilling and use something as a lubricant.) Start drilling on the cast iron side? What diameter bolts work best? Seems like I remember either 5/16" or 3/8" will do the job. Tilt the piano during drilling? Anything else I've missed? I'm excited about getting to do a new procedure! ;-) Thanks in advance. ------------------------------------------- John, I'd say the first thing is check to see where the pitch is. Generally, the pitch is low and bolting it up will give you a pitch raise.<G> I like to use the bolts that will fit the pre-existing plate lag screw holes. I use an electrician's long bit of the appropriate size. Drill from the front, (through the plate hole), with a big honkin' slow speed drill. BTW, remove the action and cover everything you can, before you start the drilling process. Remove ONE plate bolt and drill. Insert the appropriate Carriage Bolt, from the back and put plate washer on and nut. Snug it up. do the next one...etc. Once that is done....If you want to add an extra bolt in a bad area, making sure you will have tuning pin/hammer clearances, (DAMHIKT!), drill with appropriate sized Jobber bit and then through the pinblock with the electrician's bit. (DO NOT use an oil for drilling!!! Cast iron doesn't need it! AND, you don't want it going in the wrong places!<G>) Insert Carriage bolt/washer/nut..snug. Now is the time to vacuum all the chips out of the cracked/separated area. Or, use a compressor to blow the stuff out. Next, droool some cold hide glue or epoxy into the separation. Install Bar Clamps in between the bolts. Snug up on the bolts and the clamps like you were torquing an engine head. I like to check the pitch of A=440 as I do this, so's I don't get the pitch too high. Go the major grunt on the bolts and clamps, cleaning up any squeeze-out as you go. It's really easier than it sounds. If you are using Cold Hide Glue, a small bucket of water/rags is a good thing for cleanup. If Epoxy, I usually just let it set and then trim with a big honkin' chisel after it sets. Either way, the adhesive de jour will penetrate around the pins andd things will be a lot snugger..expect it.<G> Hack saw off the protruding bolts and grind smooth so that you don't get hung up on them while tuning. No need to tilt! Have fun!<G> Regards, Joe P.S. I put this on The Real Pianotech List!! (but the question was asked on the hokey one.<G> Joe Garrett, R.P.T. Captain of the Tool Police Squares R I
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