At 12:55 PM 4/2/96 -0700, you wrote: >In search of opinions! 1880 Bechstein 7' Grand. The highest treble plate >strut has a small crack from the top of the strut to 1/3 of the way towards >the bottom of the strut. > Plate welding is very difficult, especially on very old cast iron. It can be done, but to do it properly the entire plate should be preheated (cast welders should know how hot) usually in a huge oven designed for this purpose; then welded; then slowly cooled( again, cast welders should know how long) That is the best way. It can be very costly, and requires that the entire plate be resurfaced and then repainted. Other sollutions: Grind out a porion of the strut and weld in a piece of steel bar or plate, being careful not to over heat the plate ( short welds ) with lots of peaning of the weld while it is cooling. This helps reduce the formation of martensite (crysalization of the cast near the weld.) It is best not to weld across the top of the strut, just down the sides of the joint with the new steel. The new steel bar would be best shaped like a very wide 'V' tapering out towards the front and again towards the back of the piano or strut. This makes it so that there is no sharp angle for the crack to start at again. Best of luck. You'll need it. Mike Swendsen RPT Calgary, Alberta
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