>Ron, I'll have to check the thread size. I don't know right now. Yes, you >understand correctly that I didn't have threads in the plate to work with. >Do I need to tap in some new ones? > >Thanks for your response. >Ray Hi Ray, You'll need something to hold the agraffe in the plate. The plate was tapped originally and it worked quite well, so that seems like a reasonable enough method to stick with. I'm trying to determine what you have left to work with to see if we can come up with a happy ending for you. Steinway uses a 1/4" x 36tpi stud in their agraffes. If you drilled out enough of the original to get a 7/23 stud in the hole, there's still a chance that what's left of the original agraffe stud can be picked out of the hole and leave enough thread for a replacement of the proper size to work without any emergency measures. That's the "O happy day" scenario, which would naturally be the preference. If your replacement agraffe has a 1/4" stud, then life gets a little more complicated. There are a couple of potential problems with tapping new threads at this point. If your replacement agraffe stud was 7/32, then there is room for threads, but you don't want to just run a tap down the hole at random and risk (almost guarantee) cutting out the original threads and shooting yourself in the foot. Better to pick around the top of the hole with a sharp awl or some such, to see if you can find cast iron threads under brass. If so, you may be able to chase the brass out of the thread enough with the awl, hammer taps, and some muttering to give you a starting thread for a tap of the correct size to follow the original threads down and clean them out without ruining them. If you had a 1/4" stud agraffe, it's going to get uglier. Since the replacement agraffe was a force fit in your drilled hole, you may be very lucky and still have some thread left in the walls of the hole. I'd suggest the awl trick here too, followed by a 1/4x36 tap. Then I'd probably Protek the threads of the agraffe as a release agent, and JBWeld (metal reinforced epoxy) the agraffe in the hole. Hopefully, you've got just enough thread left in the plate to engage the threads of the agraffe shank and provide an anchoring key for the JBWeld. If you don't have enough thread left to be able to tighten the agraffe a bit, then there isn't enough left for this to work and you're on to the next option. Worst case: The plate hole is too big to be of any help in providing residual threads. Then I'd suggest you tap the hole at 5/16", Cut matching threads in a short length of 5/16" brass rod (thread first, then cut to length <G>), chuck it in a drill press, put a drill bit in your drill press vise, and center drill the threaded brass rod all the way through the center with about a 3/16" drill (feeding the rod down onto the drill bit and sneaking up on it in a couple of steps). Screw the insert into the plate, coated with JBWeld, to slightly below flush with the spot faced plate surface (agraffe seat). Come back the next day and drill and tap the hole in the insert to 1/4x36 for the new agraffe. From this point on, proceed as if nothing unusual had happened. The repair will be invisible from above, and as strong as anyone could hope for. Schaff used to carry 9/32x36 stud agraffes, but they no longer do. APSCO, I'm told, was (as of a year or so ago) making 9/32x34 as direct replacements for the old Mason&Hamlin agraffes. I don't know if Schaff intends to continue with this, but I hope so. Personally, I'd do the brass insert in the plate so all the agraffes are still the same size, rather than having an odd oversized one in there to surprise the future rebuilder. I hope this all makes sense. If not, let me know and I'll give it another shot. Ron N
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