On Thu, 5 Sep 1996, Ted Simmons wrote: >>Patrick Poulson wrote: >> >>This recipe seems to be 2/3rds of a solution recommended by one of my >>clients for reformulating finishes, something along the lines of one >>of the Formsby products. I believe the missing ingredient is one part >>vinegar. Patrick Poulson, RPT > >This formula sounds interesting. Is the proportion 1/3 amount of each >ingredient or is there some other proportion? I've used denatured >alcohol by itself to successfully dissolve old finishes. I wonder what >boiled linseed oil and vinegar would do to improve using just denatured >alcohol. I'm asking because I'm about to strip a piano for >refinishing. > >Ted Simmons Ted, You got lucky. Alcohol works only on shellac finishes. Shellac as a final finish was used on maybe 20% of pianos during the years 1895-1925, more often on uprights than grands. What "works" depends entirely on the original finish, and there is no point in discussing what solvent or "restorer" to use without first determining the finish to be restored or stripped. To test a finish, choose a spot in a no-critical location (such as an unexposed area behind the fallboard) apply a dab of alcohol. and rub it with your finger for a minute-- if shellac, it will become "tacky" or downright sticky. Alcohol has no effect at all on a varnish finish, and most old finishes are varnish. If a shellac finish is "virgin" (no wax or oil applied by owners), it can be easilly restored by spraying it with alcohol (denatured ethyl also called shellac thinner) just enough to thoroughly wet the surface without dripping. Then, DO NOT TOUCH the surface at all, just let it dry, and it will be clear and glossy. If necessary, repeat the spraying, or spray more before it dries, keeping it wet longer with no drips. Only after completely dry, you may consider rubbing it with fine steel wool or powdered abrasive to give it a satin appearance. Sometimes, results are spectacular, bringing out the bright grain of the wood, for only the cost of a gallon of alcohol and very little work. Bill Bailer \\\ William Bailer wbailer@cris.com \\\ Rochester, NY, USA phone: 716-473-9556 \\\ Interests: acoustics, JSBach, anthropology, piano technology
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