Hi Ron and Bob, I have seen what Bob is talking about. In fact, that has occurred on a block I am capping right now. I'd really like to see the process used to build those Multilam pinblocks because with SOME of them, when you cut off a thin layer so as to end up with the target thickness pinblock after capping, the sucker can spring into all sorts of curves. The one I am $%&#ing with now sprang into an arc with a radius of nine meters or so. When you laminate the cap on, the cap isn't going to flatten the thing much at all if you do the glue up flat. With that kind of a curve, even if you stand on the thing in the middle, it doesn't go flat - hey, even if I stand on the thing it doesn't go flat. With that kind of curve, even if I could draw it up to the plate, I would be concerned about cracking the plate or at least bowing the plate. Naw, too much curve to let me sleep at night. In these kind of cases, it seems the trick is to somehow calculate how much reverse curve to induce into the structure when bonding the cap to the block to end up with a flat block in a two lamination structure. By chance you got a formula for that Ron? Let me give you a hint: My first guess wasn't even close..... (I went overboard and actually reversed the troublesome curve!). Terry Farrell ----- Original Message ----- >> I've had a couple of problems with making and >> drilling composite blocks. Just one to bring up >> with this post. >> >> On the three composite blocks I have made thus far, >> (5/16 cap of delignit on multi-lam) I am getting a >> warping after we expoxy the two together. The plate >> web screws are able to straighten this out but, this >> isn't what I want. >> >> Does this have something to do with how we're resawing >> or planing the block down to thickness? We're not >> paying any special attention to how many laminations >> are remaining. I have heard that this isn't important >> and also the contrary. >> >> Bob Hull > > Hi Bob, > I've made a few more of these blocks, and can't say I've run > into anything I'd consider to be a problem in practice. > Commercially produced blocks aren't dead flat either, nor are > plate webbing areas, typically. As long as everything sucks up > tight with the screws, where's the problem? What are you > seeing that I'm not? > Ron N > -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20070805/80e34fb5/attachment.html
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