On Dec 2, 2010, at 5:39 AM, James Patrick Draine wrote: > Your description may be 100% accurate for all I know, but they did > indicate "it an't as easy as you think", I don't believe my description is anywhere near 100% accurate. It is very much abbreviated, but covers, I think, the basic principle: that the wool must be re-felted and made denser after it is drawn into the hole. This is done at least partly through wetting under pressure, the pressure provided by the sizing pins and the swelling of the fibers. Some may use heat. Some may do more than one sizing. Some may have a burnishing process. If anyone wants to share some of those details, I'd love to see them. In any case, my point was to contrast it with what a technician may do in the field, and to get people thinking about felt density as opposed to simply friction as the criterion for whether a bushing is up to spec or not. I believe density is more important than friction, and that friction is an indicator that should be looked at with skepticism. Regards, Fred Sturm fssturm at unm.edu http://www.youtube.com/fredsturm
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