There was some list discussion about sound board presses recently. I got the first image of my vacuum sound board laminating press prepared for the web site yesterday. The image below shows the press, with a test strip of sound board panel and one rib being pressed. http://overspianos.com.au/vacpress.jpg I haven't written a text page for the image yet. The press is 6' x 8' (1800mm x 2400 mm). The vacuum pump is a Becker 3ph 2 hp unit. A cutaway of the pump can be seen at; http://www.becker-international.com/en_z010.html It can pump 28 cfm when unrestricted and the vacuum can be adjusted from 1.5 psi to 12 psi. (12 psi will yield a hold-down pressure of around 0.75 tons/square foot - or 0.8 atmospheres). We use the minimum 1.5 psi vacuum for gluing the panel to the ribs. The vacuum diaphragm is a fibreglass reinforced vinyl, fitted to a lightweight RHS frame which can be lifted on and off the table with ease. The vacuum is delivered from the pump to the the table using the RHS frame as a vacuum plenum. A series of holes on the inner edge of the RHS allow the air to be evacuated from around the perimeter of the table. Apart from its use as a sound board assembly table, the press is also very useful for gluing veneer to panels. We will also use it for the manufacture of the laminated sound board panels which we are using for our own piano. By the way, the poser in the image is my Rottweiler 'Harry'. He likes to fossick around the workshop chewing the odd sound board off-cut. Best, Ron O. -- Ron, I also meant to comment on this and got this out of the archives as well. At some point you mentioned, either on this list or to me personally, that you were still undecided about whether to use solid boards or laminated boards in your pianos and that you were going to do some further experimentation. Since you mention the vacuum press for making laminated soundboards can I assume you've decided that laminated soundboards are superior to solid boards for giving the results that you want? Phil Ford
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