Hi Calin - First, I agree with Carl that sometimes "finishing can bring out weird problems". If ever there was a universal truth, that's one of 'em! However, one can't help but think there is actually a definable reason for such anomalies, and I have heard AND experienced more problems with lids than any other case part. My thinking is that 1) polishing is MUCH more likely to occur on the most visible and most accessible cabinet parts, and the lid is the likely candidate for having been contaminated with polishes that work their way thru a crazed finish into the wood pores and aren't always completely removed in the stripping process. The older polishes contained silicone, a substance that is an arch enemy of nitrocellulose lacquer. This seems to be particularly problematic on the older 'ribbon mahogany', with its open pore structure in the black 'ribbons'. It is very difficult to completely remove residues from these ribbons, and silicone is non-soluble and very difficult to extricate. A standard practice of sealing the stripped, sanded wood with shellac is a practice that can practically eliminate problems with subsequent coats. Alternatively, "sili-check" and other similar additives can be added to the lacquer to eliminate this problem, but some film strength integrity is compromised. 2) Another possible cause of your problem, and I am just guessing, of course, is that it is far too common that big horizontal pieces receive coats that are WAY too thick, just because there is no possiblity of getting runs and sags. Spraying vertical surfaces requires a much more prudent amount of material be applied, and not surprisingly one encounters fewer problems with dry times on these pieces. Lacquer can keep a soft 'belly' for a very long time when applied too thick, and that MAY be part of your problem. Taking pot shots in the dark..... Mark Potter bases-loaded@juno.com On Tue, 19 Aug 2003 19:09:04 +0300 "Calin Tantareanu" <dnu@fx.ro> writes: > Hello all! > > We have started spraying the small part of the lid of a Hamburg > Steinway O > (can be seen on my website http://calintantareanu.tripod.com/piano/ > ) on > Sunday and the nitrocellulose lacquer (colored black) isn't dry even > today, > in some places. Why is this happening? > The same lacquer sprayed on other parts of the same piano (music > desk etc.) > dried > properly. > I should mention that this is the first coat, on the sanded veneer, > and that > the piano was previously finished in black shellac (I think). > > Thanks for your help! > > > > Calin Tantareanu > ---------------------------------------------------- > http://calintantareanu.tripod.com > ---------------------------------------------------- > > > > > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives > >
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