>It appears that the several of the plate suspension bolts >(square heads) are bottomed out (bolt head is flush against the >soundboard. I am guessing that I have two choices: >1: slightly countersink the suspension bolt heads into the soundboard >2: grind some metal off of the bolt heads. > >Larry Toto Hi Larry, You can countersink the soundboard or grind the bolts. Either would work fine. You could also replace the bolts with large flat head wood screws so you could "V" countersink under them and not chew up as much soundboard material if that's a concern. You could also replace the screws with dowels and not have to countersink at all, but you lose the easy adjustability as a trade off. Or you could dispense with the support bolts altogether and replace the hold down lags or screws with either Jim Coleman Jr's adjustable plate bolt system, or make your own with large socket head screws, lock nut and acorn nut. With either of these you can adjust plate height from above with the plate in. There are lots of workable options. I presume you have measured crown in all areas of the board that you can reach and verified that the low bearing readings aren't the result of a collapsed soundboard, in which case just adding bearing won't do you much good anyway. If you had positive crown everywhere you could measure before teardown, you're probably all right, but I'd recommend not adding a whole lot of bearing in any case on an old board. Add a little to the top end, keep it light overall, and even it out a bit. With the light bearing you indicated in the top half, if there was no crown, or negative crown anywhere on the board you could reach underneath with a string (not just along the longest rib), the soundboard is probably dead. Good luck, and let us know how it worked out. Ron N
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