>You are, as usual correct. Not me, the reference material. It's in one of the books I go to when I want information more reliable than consensus of opinion - my own included. >But, one of the premises of tempering or >annealing is: heat/cool, heat/cool, heat/cool, etc. This process, (so I've >been told), is dependent on the cooling process and the amount of heat. >Slightly heating steel over and over will tend to anneal, (soften), and can >cause the strength to deteriorate. I don't know if 95 degrees would be >enough to do this, but without a consistant cooling medium, I think that it >might. But it isn't cycled. The current remains on. If the string is being electrically heated, it's kept at at least as constant a temperature as a piano in someone's home, and a considerably more stabile temperature than the average church or school piano. Even if the temperature were cycled (like that church or school piano), the high temperature ranges are far below those necessary to affect the wire temper. Going back to the same book, I find that fully hardened steel consists largely of martensite. Reheating it to between about 300° and 750°F, a softer and tougher structure known as troostite is formed. Reheating to from 750° to 1290° forms a structure known as sorbite, which has somewhat less strength than troostite, but much greater ductility. All of this stuff happens some ways above 95°F. Of course, there may be effects I don't know anything about that will kill the idea, but as you said - time will tell. Maybe. >On this mechanism/piano, I think that only time will tell. Yes, if even then. >As for me, I don't percieve this as a threat to my livelyhood, but rather >consider it an oddity of our industry's on-going R&D, albeit, a little >wacky, IMHO.<G> >Joe Garrett, RPT, (Oregon) No, no threat, but surely not a waste of time and money either. There's something to be learned here. Ron N
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