Phil wrote a very good post about felt: > And in a previous post I was trying to convey the idea that the >makeup of the felt itself is important .... Also the point I was making, which is why we have been studying the compression properties of (different types of) felt independently of piano hammers. We can't hope to understand the effects of hammer-making operations until we know a bunch about the felt material they're made from. > Can you imagine anyone in the world being willing or able to supply such a >thing in 2004? Forget it. In 1904, probably. But we've made 100 years of >'progress' since then. Well I can actually imagine it in 2004. There is clearly a market, albeit a niche one, and an available product that could fill that need would probably sell. I think the problem is missing knowledge: (a) we don't really know what properties of felt are desirable for hammer-making; (b) we can't quantify those properties; (c) we don't have ranges or desirable targets for those properties; (d) we don't know how the raw material (wool type) relates to the finished felt product properties; (e) we don't know the relationship between the processes used in felt manufacture and the mechanical properties of the finished product. In other words, lots of don't-knows, and consequently much speculation. We've come some of the way to answering (b), and have hints about (a), that after several months of experimentation. By the way, a traditional way to full felt was rolling it up in a cloth and and roping it onto the back of your horse all day....pressure from trampling, heat and liquid from other obvious sources, all the essential components. Stephen -- Dr Stephen Birkett Associate Professor Department of Systems Design Engineering University of Waterloo Waterloo, Ontario Canada N2L 3G1 E3 Room 3158 tel: 519-888-4567 Ext. 3792 fax: 519-746-4791 PianoTech Lab Room E3-3160 Ext. 7115 mailto: sbirkett[at]real.uwaterloo.ca http://real.uwaterloo.ca/~sbirkett
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