> /Ron O wrote: / > /> I pulled one original board which > > clearly had lots of crown when it was installed, but the inner was > > made flat. The glue joint was good around the outer edge but the > > inner edge was only just making contact or just off the rim./ > // > Sound to me like somebody needs to learn how to either spread glue, or > more likely clamp a glue joint thoroughly! I'd say. > I've started to use a method that Ron N shared with me. I cut strips of > scrap plywood the shape and width of the inner > rim/belly-rail/fish/cut-offs/etc., place them on top of the soundboard > and use those pieces as clamping blocks. I think use of such blocks, > along with numerous clamps, insures a pretty darn good glue joint - oh, > and good glue surfaces and good glue and the proper amount of glue and > anything else I have neglected to mention. > > Terry Farrell That one was from Shawn Hoar. I've always been a fan of clamping cauls for more even pressure with fewer clamps, so when he mentioned this in one of his tools and methods classes, I thought it was a good idea and stole it. Realistically, with modern glues like Titebond, that's a fairly non-critical joint. As long as it has enough glue to squeeze out under clamp pressure, fill irregularities, and not buzz, it just has to keep the negative bearing from pulling the collapsed board off the rim in later life. And since a well designed board isn't likely to collapse, a joint quality you'd build into a chair and hope to sit on is more critical. Going back to the thread, It never ceases to amaze me that people will accept as natural and desirable the immediately and permanently destructive panel compression levels produced in compression crowning, while worrying about putting undue strain on the board by gluing it to a plane surface around it's perimeter. It's a non issue, for the most part. Ron N
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