YES!!!!! Use "Duravar" from M.L. Campbell. This is a bowling alley, 2-part varnish, VERY hard! I believe that I have successfully recrowned a board by 1) Screwing a 2x10" plank to the back of a piano, in a climate controlled finishing room with the humidity as low as possible, with a tracing on the plank of the bridge curve ( mylar pattern ) 2) Drilled holes in the plank to correspond with the intersection of rib to bridge line on other side of soundboard. 3)Throughly screwed down soundboard to rim from front with retaining strips, etc. 4)Tapped threaded inserts into plank holes ( cheap, from hardware store ) 5) Made saddle blocks to ride, protect ribs . 6)Screwed 10" long, 3/8"diameter bolts through plank to press on spoundboard from back,on saddle blocks, along bridge line, until I just started to hear splintering. 6) Mixed up some Duravar, and thinned 60% with lacquer thinner ( guesstimate ). 7) Sprayed on soundboard, front and back, to soak into board. My theory was that, by adding some material to the board, I could compensate for compressed spruce fibers, and regain crown. I went back with several coats, thinned progressively less. 8) Let it all cure for a couple of months while doing something else. This stuff permits loads of formaldehyde while curing, so you want a separate shed to do it in! 9) Take off brace, and string. I just did this to a non-descript 1922 Krakauer upright, and it REALLY sounds better than the Steinway uprights, same size, at University!!! I believe this is due to regained crown, as well as the severe hardness of this stuff passing string vibrations across the face of the board like lightening! I also thinly coated the bridges with West's epoxy, wafted over by heat gun ( before doing board ). This piano is in a church with very unstable climate. It sounds amazingly nice, and they love it! I also intend to put a thin polyethylene sheet across the back, covered with speaker cloth, and foam weatherstrip under lid edges, etc., to keep air from circulating within. TIP: To avoid buying $500 explosion proof exhaust fan for your finishing shop (that sucks in bugs and dirt from everywhere else) go get alittle poratable building, 10'x 12' or larger, and build a wind tunnel on the back of it, into which 3 cheap, window "box fans" can be stuck in a row, to push air INTO the shop, through furnace filters. On the other side, have screen window. This is how I made mine, with Sears dehumidifier draining outside, and all very shutterable for humidity control. Electrical conduit on ceiling with loops of cord connect to screw eyes in piano panel pieces ( almost every panel has a place to screw them in!)can hang up all panels like this, spray both sides, let hang to cure. TOTALLY DUSTPROOF!!!!!( Almost fun! ) Gordon Stelter --- Ron Nossaman <RNossaman@cox.net> wrote: > > >Has anyone you know of experimented with a > different, impervious material > >for soundboards or a sealing technique that would > take a lot of the > >humidity factor out of pitch stability? > > > >Alan Barnard > > > For one: > http://www.speech.kth.se/music/5_lectures/conklin/newmaterials.html > > But then there's the rust... > > Just putting ribs on both top and bottom of a > conventional board, solid or > laminated, should make a substantial difference. > > Ron N > __________________________________________________ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com
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