Hi, Don - Interesting problem, one I've not yet encountered personally. If you use new wire, of 0.072" diameter, you'll be looking for a No. 1 die to cut the thread. (No. 2 would be 0.085" or 0.086" for the major diameter of the thread.) The closest you'll find for off-the-shelf dies would be 1-64 thread, which is the standard coarse-thread. (Standard fine-thread is 1-72.) I wouldn't worry about exactly replicating the original "Chickering Standard Thread", since the dampers don't really have to be interchangeable with one another. In any case, you'll probably want to renew the threaded hole in the damper flange. To do this, put a drop of glue into the hole, preferably epoxy or slow-set CA. Coat your new threaded wire with Teflon spray or mold release and press or screw (depending on the fit) into position. It should be inserted a little farther into the flange than the finally-regulated position, to ensure room to regulate later. Turn the damper wire in the flange once or twice just as the glue is setting up and you'll have a strong and just-right thread in the wood. Best of luck to you, Don. Best regards, - Tom McNeil, RPT - Vermont Piano Restorations
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