BSimon1234@AOL.COM wrote: > Has anyone out there gone hi-tech and used kevlar or boron or carbon fiber > patches on the sides of keys broken at the balance rail hole? > > If so, I would like to hear about your experiences. ----------------------------------------- I've tried it a couple of time with carbon fiber. The procedure is fairly simple. Glue the key back together as normal. Mostly the broken keys I've encountered have the hole for the balance pin way off-center. So the re-inforcing material goes on the thin side. Spread epoxy on the side of the key -- my repairs are all done in the shop where curing time is not usually an issue and where we use WEST System epoxy -- and lay 1" carbon fiber tape across the crack. Align the tape to the top of the key body -- do not overlap the button. Any excess that overlaps the bottom can be trimmed off after the epoxy has cured. I used strips about 6" long. The repair worked nicely, if a bit messy and unsightly. I'm sure the repaired keys were quite strong. In the end, I couldn't convince myself that this worked all that much better than my old standard, 1/32" (or even better, 1.0 mm) maple veneer. So, I've gone back to sistering the broken area with strips of maple veneer trimmed to fit the full height of the key and sanded nicely after everything has dried. This repair looks good and is also exceptionally strong. To the best of my knowledge none have ever re-broken. Usually, even though the buttons will be cut pretty thin on one side, I leave them alone. That is, I do not normally extend the maple veneer up to cover the side of the button. If the button is that badly mangled it gets replaced. And if it is replaced the new button will be trimmed to fit the full width of the key body. That is, the width of the key body including the new maple veneer strip. Hope this all makes sense... Regards, Del
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