Totally unscientific, but I had occasion to try VS on a hammer-pinning center from a Steinway action I was 'de-verting' for a friend who just needed the action free enough to have an idea of what the piano sounded like. I was using naptha and aggressively working parts (dismounted from the frame...in-place did not seem to work). Once dry, some seemed to have been worked a bit too aggressively, and were loose. I applied some VS to the pinned assembly, but it was still too loose when dried, which is what Fred explains below. I unpinned and reapplied VS (sparingly) and left center unpinned. When dried, I had to refit pin in (almost) normal manner, and it worked very nicely. Don't know about longevity. Next time I might try sizing with a pin one or two sizes under. David Skolnik Hastings on Hudson, NY At 08:52 PM 12/16/2008, you wrote: >On Dec 16, 2008, at 2:52 PM, Chris Solliday wrote: > >>Alcohol and water depends on the amount of water, more is more >>aggressive, but in any case my findings were that VS Profelt is >>more aggressive in general as a sizing solution. > >There is a pretty obvious reason for this: VS Profelt has a very >high ratio of water in its contents. I believe it is in excess of >75% water. It's pretty rare that we use an alcohol and water mix >that is 1:3 alcohol to waterl. More common is the opposite, 3:1 >alcohol to water. So if you want to compare, it would be a good idea >to use a few mixes of alcohol and water to compare to VSP. Maybe >3:1, 2:1, 1:1, 1:2, and 1:3. Or just 3:1, 1:1 and 1:3. I think that >would give a pretty fair comparison. (That is, the 3:1 water to >alcohol would be a fairly even match, the others would be >instructive as alternative strengths). >About the notion concerning action centers, I don't think a high >water ratio there would swell the felt to take up space, like in key >bushings, for the simple reason that it is a system that requires a >lot more compression and a tighter final fit. If you add a higher >proportion of water, it causes more knitting of fibers, hence more >"shrinkage," resulting in a looser fit. The "shrinkage" is actually >felting, locking the fibers together more tightly. When you apply >the stuff, the action centers seize up (applying more compression). >When the water evaporates, the more compressed fibers leave space >between them and the pin. >It works for key bushings because there is lots of extra space to be >filled in to start with, and you actually want a somewhat loose fit >(compared to action centers). > >Regards, >Fred Sturm >University of New Mexico ><mailto:fssturm at unm.edu>fssturm at unm.edu > > > >No virus found in this incoming message. >Checked by AVG. >Version: 7.5.552 / Virus Database: 270.9.18/1851 - Release Date: >12/16/2008 8:53 AM -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/caut_ptg.org/attachments/20081217/327b9da4/attachment.html>
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