I have had plates succesfully welded and they have held for as long as I have since seen the pianos. One has been holding for 30 or so years. As you will be rebuilding the paino, all you have to make sure of is that there is no stress on the plate after it is reinstalled. The plate has to be laying flush with the framework and the nosebolts cannot be causing up pressure or down pressure. eg. trying to improve downbearing by stressing the plate. You should place the level of the plate to have enough downbearing at the lowest point of the bridges and if you find there is too much downbearing in certian areas, shim up the strings where they touch the plate and cover the shims with felt, or if it is at Steinway type, shim up the aliquots. For shimmimg I have used cardboard (.025" or so) and glued several layers together and squeezed them in a large vice, the pressure of the vice usually compresses the cardboard by about 20%, then in the places that are too thick, I sand down the cardboard until I get the desired thickness using a hammer reshaping paddle. Hope this helps, Ray Hopland RPT
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