Crazed Finish On Music Box
By Craig Brougher
Nancy Fratti mentioned a box shipped to her with a one year old lacquer finish which had crazed during the shipment. This is more apt to happen to the two-part lacquer finishes, like as used on the bright finished pianos. I knew of a concert grand being shipped by truck. It was caught in a frigid snowstorm, continued to its destination, and when it arrived, it was crazed all over like safety glass. I have been to seminars about the problem, and we also learned to repair minor cracks, but for small boxes, I wouldn't recommend that finish.
I believe that one of the reasons finishers have had to go to these finishes is because of the outrageous costs of lacquer resins, like the type they still used in the 40's. When I started finishing, even in the 50's, the lacquers were excellent. By the 70's, they had been cheapened up considerably. They were softer and more plastic, and they continued to shrink over the years, eventually either grain checking or showing texture that hadn't been there 5 years ago.
It seems to me that chemists that work for paint companies don't really check on their products for general market use as carefully as they should. Their primary tests are usually made on pine or poplar (softwood) boards with fine grain structure (table leg stuff), perhaps 6" square, and they do not consider the vast differences in wood types, like mahogany versus white pine, nor the differences in method required to seal and coat them. That is why it takes a long time to find a combination of good products, and about the time you've found them, they are discontinued or changed without letting you know. A refinisher must always find out the hard way. I know of no paint company willing to admit to changes in their products. On the other hand, I don't know of any good refinishers who don't quickly realize that their lacquer has been changed on them.
Resins are the expensive part of a finish, and some companies shop for them by price, mainly. But as any lacquer formulator knows, different resins have vastly different hardness and elastic characteristics, aging qualities, buffing and finishing qualities, and different tendencies to trap the solvents in a five or ten year long-term test. A year or two doesn't really tell the company that much about a product designed to coat mahogany for 50 years or more, and they won't guarantee even the most obvious of formulation errors. So while they tell you that their environmental chamber ages a finish for 50 years and show you their finish after exposing it to the affects of humidity and temerature changes, all I can say is, "Don't they wish!"
Craig B.
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(Message sent Sat 2 Nov 1996, 15:29:03 GMT, from time zone GMT.) |
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