Excellent observation! Paul In a message dated 2/14/2011 8:09:48 P.M. Central Standard Time, davidlovepianos at comcast.net writes: Well, even if it’s not a completely hollow core if the interior of the wool fiber tends to absorb liquids due to the orientation of the cells or grain structure (whatever that is) it does raise the question as to whether, first of all, the lacquer gets into the interior of the outer sleeve and second if it does will soaking the wool in a thinner be able to extract the lacquer from the interior. It’s easy to imagine that the lacquer my both get absorbed into the interior of the outer tube and also coat the exterior of the tube. Soaking the hammers in thinner for purposes of extraction might well float the lacquer off the exterior of the fibers but might do less well extracting it from the interior. That would concur with some people’s experience (as Dell said he experienced) that soaking might improves things somewhat but it’s not quite like starting over with a fresh, unadulterated piece of felt. David Love www.davidlovepianos.com From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of Fred Sturm Sent: Monday, February 14, 2011 5:43 PM To: caut at ptg.org Subject: Re: [CAUT] Rinsing lacquer from hammers >From wiki: "Wool fiber exteriors are hydrophobic (repel water) and the interior of the wool fiber is _hygroscopic_ (http://en.wikipedia.org/wiki/Hygroscopic) (attracts water)" if that makes things clearer. And a schematic diagram from a web search shows no hollow core. On Feb 14, 2011, at 6:22 PM, Fred Sturm wrote: On Feb 13, 2011, at 8:40 AM, Dale Erwin wrote: I'm curious. I learned from Jack Brand (during the Weickert felt trials) at Wurzen felt that wool fibers are hollow, which is why they can hold so much moisture. ie rugs, sweaters etc This statement caught my eye, and has made me wonder. Are wool fibers, in fact, hollow? I sort of doubt it, but I don't know. Does anyone actually know for certain? My take on wool absorbing water is not that there is a "hollow spot inside to hold it," but that the wool fibers themselves (that is, the material itself of the fibers, the proteins I suppose) "attract" and "absorb" the water (quotes because I'm sure there are scientific terms for these things that I don't happen to know). Kind of like the protein in gelatin, or in hide glue. In any case, the individual fibers do swell in the presence of water - I am pretty certain of that. In swelling, they spread out their little scales so that those will tend to interlock with the scales of other fibers, all of them being pressed more tightly together because the space between them is taken up by all of them swelling, if they are constrained in some way (as in center bushing felt, for instance, constrained between the pin and the wood). This is a part of the felting process. Do they swell with lacquer, or the various solvents associated with it? I don't think so. In any case, drenching hammers in lacquer thinner, acetone, or alcohol doesn't seem to make them expand, or leave them larger than before. Water does make them expand and they end up larger than before. So I don't think we know whether the solids in lacquer penetrate the wool fibers when we dope hammers. I have always pictured it as coating the fibers. And have wished that someone would do electron micrography on lacquered hammers so we could see. Regards, Fred Sturm _fssturm at unm.edu_ (mailto:fssturm at unm.edu) _http://www.youtube.com/fredsturm_ (http://www.youtube.com/fredsturm) Regards, Fred Sturm _fssturm at unm.edu_ (mailto:fssturm at unm.edu) _http://www.youtube.com/fredsturm_ (http://www.youtube.com/fredsturm) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/caut.php/attachments/20110214/c41dcf1b/attachment-0001.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/unknown Size: 116506 bytes Desc: not available URL: <http://ptg.org/pipermail/caut.php/attachments/20110214/c41dcf1b/attachment-0001.bin>
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