On Feb 18, 2010, at 3:14 PM, David Ilvedson wrote: > 8:1 solution? > > David Ilvedson, RPT > Pacifica, CA 94044 With reference to what? What Steinway uses to dip a whole set? That solution is something on the order of 3-4% solids, which is 3:1 of what they had been using before to finish pianos, but then became 6:1 or so when they changed suppliers. That's what I am remembering. The problem is that ratios mean nothing unless you know the concentration of the original, and that may vary a lot. Which is one reason we tend to talk at cross purposes about the use of lacquer. I remember being told very specifically by Ron Coners that what they used was 3:1, and being rather shocked that they would use such a strong solution. What he meant was 3 parts thinner, 1 part lacquer, so another way you could express it is 25% solution (which some people might express as 4:1, or maybe as one in four). It turned out (I learned a couple years later) that they went to the finish room and dipped some out of the supply there. And that lacquer had probably been pre-thinned. Eric Schandall finally clarified that what they started with was about 12% solids (if my memory serves), I think by weight, if that makes an appreciable difference. And then maybe five years ago something changed in the finish room (maybe a different supplier), and they went dipping and found the results were "a wee bit strong," and they discovered the concentration had changed. Or so I remember hearing. My lacquer off the shelf is in the 20%+ range for solids content. So about 6:1 mix of that gives 3-4% solids. Maybe someone else has more precise information. Memory does blur a bit over the years. Regards, Fred Sturm University of New Mexico fssturm at unm.edu
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