Dave Slight Report post Posted October 28, 2020 1 hour ago, sospiri said: Not even a tiny bit more longitudinal shrinkage? So is it mostly in the belly and back, causing the ribs to bulge? Does it vary a lot in old instruments? In general, wood shrinks such a small percentage along it’s length that it can be discounted as a factor here. The back and belly both shrink across the width, the ribs don’t shrink. From this stress, the ribs will start to bulge (they are effectively forced into a longer and narrower shape) near the end blocks, eventually popping the seams open. You will then find that you can’t push the ribs back into position to glue them. Over time, the disparity increases. The ribs will eventually exceed the margins of the belly and back, requiring them to be shortened, along with the linings, in order to restore the correct amount of overhang. Larger instruments suffer from this much more, so if you want to see it for yourself, an old cello is often a good candidate. Look either side of the tail block. In extreme cases, the stress can start to crack the ribs at the edge of the block. Quote Share this post Link to post Share on other sites
