Also, recall that the ribs are of variable radius so clamping them into a preformed caul for glued just helps insure that the radius is maintained. Probably not that big a deal in terms of outcome. Still the melamine pattern would have to be made for each board which isn't practical unless you are doing the same board over and over. Also, it's messy. With squeeze out and the vacuum bag you'd conceivably have glue smearing around at the glue line. With the press method the squeeze out is accessible even while clamped. I suppose you could do it the way you suggest but I'm not sure what the benefit would be. David Love www.davidlovepianos.com -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Greg Newell Sent: Sunday, June 13, 2010 8:54 PM To: pianotech at ptg.org Subject: Re: [pianotech] Fire hose failure! David, Not sure what you mean by the last sentence. If you've made the ribs radiused in a caul what further need do you have for a caul? At that point your just attaching ribs to the board and with the melamine cut in a negative rib pattern trying to prevent them from sliding around while the bag draws down the vacuum. The ribs already have the radius needed and the board will conform to them. I'm assuming built up ribs not cut ribs. Greg Newell Greg's Piano Forté www.gregspianoforte.com 216-226-3791 (office) 216-470-8634 (mobile) -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of David Love Sent: Sunday, June 13, 2010 1:39 AM To: pianotech at ptg.org Subject: Re: [pianotech] Fire hose failure! I suppose if you were making the same board over and over again but since I'm not it's a lot of additional work. Also, one thing that happens is that the ribs are pressed down onto the panel and into a caul matching the radius of the ribs (even though the ribs are crowned) which is harder to manage with a vacuum press. David Love www.davidlovepianos.com -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Greg Newell Sent: Saturday, June 12, 2010 9:46 PM To: pianotech at ptg.org Subject: Re: [pianotech] Fire hose failure! You sure about that? If you use a template made of that melamine stuff to locate the ribs and tape the board to the melamine it works quite well. Cut slots into the melamine and the ribs sit in the cut slots and are then sandwiched to the soundboard locating them well and preventing their movement while the bag vacuum clamps it all together. I'm assuming ribs that aren't flat. Works quite well actually. Greg Newell Greg's Piano Forté www.gregspianoforte.com 216-226-3791 (office) 216-470-8634 (mobile) -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of David Love Sent: Saturday, June 12, 2010 9:30 PM To: pianotech at ptg.org Subject: Re: [pianotech] Fire hose failure! Doesn't work for ribbing. David Love www.davidlovepianos.com -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Greg Newell Sent: Saturday, June 12, 2010 2:58 PM To: pianotech at ptg.org Subject: Re: [pianotech] Fire hose failure! A large vacuum bag. Greg Newell Greg's Piano Forté www.gregspianoforte.com 216-226-3791 (office) 216-470-8634 (mobile) -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of David Love Sent: Friday, June 11, 2010 11:15 PM To: pianotech at ptg.org Subject: [pianotech] Fire hose failure! Ribbing a board today I discovered that my pneumatic clamps (firehoses) had all sprung leaks to the extent that my compressor wouldn't keep quite enough air pressure (argh). So, while I did fashion a remedy for the short term I'm shopping to replace the fire hose material with something a bit more air-o-dynamic. Any suggestions? David Love www.davidlovepianos.com
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