Knabe cracked plate

[Nichols]

David,
    Without examining your particular piano, I can still suggest 
reinforcing bars, or struts. We've seen repaired plates fail right at the 
"end" of a layered strut. We kick ourselves for making the strut short, and 
fix it again. Once there's enough strut to reinforce a whole section of 
original plate strut, then the breakage stops. Sandwiching the plate is 
good, also. Making sure that the plate is evenly heated when welding seems 
to be important, also. So far, so good, with almost too many to count. Our 
"outside" welder does a lot of engine blocks, and knows his iron.

Good luck,
Guy Nichols


At 04:24 PM 9/23/2005 -0400, you wrote:
>Friends,
>Here's another question about my 1900 Knabe 6'4 grand. The plate is
>cracked. The cracks are in the two treble bars, and just above the
>pinblock. I am planning to take it to a welder whom I understand is the
>best qualified person to work on piano plates in the state of Ohio.
>However, I just read an article in the Journal (June '03) written by
>B.M. Patchett, et.al., discussing a plate from a mid-1800's Schiedmayer
>which was cracked in the same way as mine. The authors made a bunch of
>measurements and created a model of the stresses and came to the
>conclusion that the plate would fail again even with the best welds in
>the world.  They ended up adding steel reinforcing bars to the tops of
>the treble bars. Well, now I'm wondering if my Knabe is in the same
>boat. Any wisdom ??
>
>thanks.
>David B. Stang
>Columbus, Ohio
>
>
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