David - It sounds to me like you were using some shellac that was past its shelf life. I have never heard of it "letting go" of any surface that was reasonably clean, nor have I EVER heard of lacquer having any compatibility problems with shellac whatsoever. However, when shellac gets old it will never set up, remain kind of rubbery, and crinkle easily, and I could see it possibly shedding a top coat placed on it. Finishers have been putting lacquer on shellac for many decades. I did on a regular basis back in my nitrocellulose days with never a hint of a problem. Also, I have been putting it under lacquer on plates, both in the clear form and with powder suspended in it, for over 20 years and never had the experience you did. I continue to service many of these instruments and would know if there was a delamination. I will ask the refinisher's forum I subscribe to if they may be able to shed some light on your problem. Mark Potter bases-loaded@juno.com On Sat, 07 Jul 2001 21:20:05 -0000 "David Stanwood" <dstanwood@hotmail.com> writes: > > WARNING! > > Years ago I used shellac as a sealer for plates and after a few > years the > finish started to crackle and in some cases peel off in sheets. I > found the > solution in a product call Silicone Stop Sealer which was made by > Mohawk. I > have two gallons left... but I called the factory and they put me > through to > a chemist who told me that it is half shellac and half lacquer. > > The way I use it is to spray on as an undercoat then when it is > quite dry I > spray Utilac gold in a spray can... this alas is discontinued as > well. Then > I mix about 1/3 orange shellac with the silicone stop seal and > overspray the > gold starting with a very thin coat then spraying until the right > golden hue > is had... > > I love the look, warmth, and feel, especially in tungsten light.... > > I treat the Steinway action rails the same way and it looks almost > like > polished brass.....but without the eventual tarnish. > > Shellac reacts with metal and I had some bad experience mixing > shellac with > the powder but I think some experimentation with lacquer/shellac is > worth > while... > > David Stanwood > > >From: "Erwinpiano" <Erwinpiano@email.msn.com> > >Reply-To: pianotech@ptg.org > >To: <pianotech@ptg.org> > >Subject: Fw: shellac sealer on plate yes yes yesYES > >Date: Wed, 4 Jul 2001 07:20:08 -0700 > > > >Very interesting post Mark Potter. Once again it may have taken me > another > >decade to think of that all by myself but I catch on quick after a > long > >time! > > Thanks > > > > DAle Erwin > > > > > >----- Original Message ----- > >From: bases-loaded@juno.com > >To: pianotech@ptg.org > >Sent: Wednesday, July 04, 2001 4:10 AM > >Subject: Re: shellac sealer on plate yes yes yesYES > > > > > >On Tue, 03 Jul 2001 21:43:09 -0700 "Diane Hofstetter" > ><dianepianotuner@hotmail.com> writes: > > Dale, > > > > Me too, I offer up my gratitude to all who suggested shellac! > > After two coats of spray shellac, sanding in between all coats, > and a > >coat of gold enamel, the fish-eyes are gone and tomorrow I can put > the top > >clear coat on. Whew! > > > > Diane > > > > > > Hi Diane - > > > > I'm glad it worked out for you so well! Yet another alternative > for you > >would be to mix bronze powder right in with the shellac and use > that as > >your finish, or at least as a primer/sealer coat that already has a > bronze > >color. I have done it many times with good results every time. > Use the > >palest color of shellac you can find, though, as a dark shellac > will yield > >a darker gold color when mixed with the powder. > > > > Shellac is a finisher's right hand man. > > > > Mark Potter > > bases-loaded@juno.com > > > > > > _________________________________________________________________ > Get your FREE download of MSN Explorer at http://explorer.msn.com > >
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