Scott Nelson wrote: > What was interesting was under favorable lighting conditions, you could > see the horizontal lams statring to split apart and lift at many of the > bridge pins, almost as if the pins were leveraging the cap apart where > it was weak. I used to think that the laminated structure would be > stronger, but apparently the material was yielding in this case. Laminated stuff is prone to that. It's not that difficult to damage the top lamination. The advantage is that the damage doesn't propagate further into the structure, like it will with solid wood. The more impregnated the layers are with glue, the less prone to damage the outer layer is. An example is Baltic Birch plywood. It's wonderful stuff, hard and stable, terrific to work with. But it's not held together with a lot of glue, and the face veneers chip and splinter easily. > Could this be an example of the Delignit bridge capping material you > were referring to? No. The Delignit stuff is 90° cross plied, and very stripy looking. Those laminated caps in the new pianos look to me to be a parallel, or near parallel, lamination. I don't know if they're making it themselves, or if there is a supplier out there in the world somewhere that makes it for them. I know the Permali folks will make high density low angle laminates from Beech, but the stuff I've seen in pianos looks more like maple. >If so, it would seem that your use of veneer or > thinner plies with epoxy saturation would indeed be more structurally sound. It seems to be, which was the plan. Ron N
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