For aligning plate to case, here's what I do: Make two "headless screws" by sawing the heads off of two #18 x 3" wood screws, and slot the ends with hacksaw or dremel. Before removing the plate, drill two 1/4" holes down through the plate and into the rim, near each end of the long bridge. (Caution - locate the holes slightly off from the midpoint between plate bolts to avoid drilling into the button screws on M&H grands) Re-drill the plate only to 5/16 diameter, and screw the headless screws into the rim until the the top of the screw is flush with the plate. For plate height, measure, or mark story sticks, from the top of the plate to the top of the rim at the front bass corner, front treble corner, and tail. Now the plate can be returned precisely to it's original position even after the old pinblock is out and the new one not yet fitted. For fitting a pinblock to the plate and to the rim/stretcher, Ed's system can't be beat. Although you didn't ask about it, there will be times when the original plate location will not do. If the piano has issues with strikepoint , action geometry / capstain line, bridge thickness, or string height, you should at least consider whether relocating the plate might be part of the solution. I find myself raising plates fairly often, but have not yet had to move one horizontally. Mike Spalding Ed Foote wrote: > Ph illip asks: > > Before removal, I generally mark a piano plate location using > wedges and taking several plate-to-rim measurements. I've often > wondered how much "play" a refitted plate will actually have since > it's held in with a few dozen screws and bolts. What preparation > and notations should be taken before removing a plate? > > If the block is to be fitted tightly into the case and > stretcher, with the plate in the original position, I drill four index > holes, same dia. as a #7 bridge pin,(two on each end) in the corners > of the plate, directly into the block. Then I lift the plate enough to > place a pair of cardboard templates on top of the block, fitted > exactly into the corners against the stretcher and sides. I tape > these two templates in place, reinstall the plate and drill holes > through the cardboard. Pull the plate, fit an oversized new block and > screw it to the plate. Drill through the holes again, into the new > block. > Remove new block, fit the cardboard templates over #7 pins > that have been installed in the holes and draw a pencil line where the > stretcher and sides are. Cut the block ends, taking the pencil line > with the kerf. You will be within .010" of a tight fit. The cut to > fit against the stretcher is made with a line drawn against a > straightedge laying against the cardboard's proximal edge. When > cutting that one, leave the pencil line. > For insurance, I also measure plate height at the pinblock ends > and I use a wedge between the tail of the plate and the case to make > certain there is not slight rotation of the plate. On many Steinways, > you will find a plate rise at the tail when the rim and nose bolts are > removed. I don't know if this is prestressed originally, plate warpage > (doubtful,since I don't think cast iron warps), or perhaps the case > has worked during the piano's lifetime. In event of a rise, I put a > wedge under the tail and record the rise, since when I reinstall the > block, I do it with it fastened to the plate, and if there is a rise > to the tail, I want to keep it that way. I put the 'rise' wedge back > in so that the block will remain at its original angle as it is bedded > down on the inner case and stretcher with West epoxy. Next day, I > remove the plate, install dowels thru the block into the inner rim, > and go on with the rest. > Hope that helps. > > > Ed Foote RPT > http://www.uk-piano.org/edfoote/index.html >
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