This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment Oops... My email was delayed, due to an internet problem. My question = about grinding the capo had already been answered. However, what about = the magnetic hardening? This is usually done with higher tech alloys, = not gray cast iron. But can it be done with cast iron??? =20 Regarding the prospect of setting a steel rod in a groove ground in the = capo... What dia of rod? Also, is spring steel the best choice -- i.e. = like piano wire? Peace, Sarah ----- Original Message -----=20 From: Sarah Fox=20 To: Pianotech=20 Sent: Saturday, January 25, 2003 1:27 AM Subject: Re: Capo Hardening, was: Tuning problems under capo bar I've wondered about this myself. My Wissner's capo is very badly = grooved. I've shifted some of the strings slightly to eliminate their = "zinging," but the capo will obviously need reshaping. As far as I'm aware, different metals are hardened via different = methods. However, the fact remains that this usually involves heating = and cooling for various periods of time -- something that's hard to do = with something as large as a harp -- and difficult to do without = stressing the metal and risking a crack. I believe some ferrous alloys are hardened with magnetic fields, = perhaps with moderate heating. Perhaps this could be a useful = alternative? I have no idea how this is done, though. Alternatively, does anybody ever grind the original capo off and = overlay a hardened bar, fitted for height? It could be epoxied in place = for a tight mechanical contact. Of course this begs the question of = what happens when a capo is ground and filed and ground and filed and = ground and files -- until the downbearing is inadequate. Yes, I know = the plate can be lowered, the bridge can be built up, the aliquot plates = can be filed, etc., but does this ever present a problem, such that a = technician might decide to rebuild a capo? Peace, Sarah Fox=20 (Columbus, Ohio) ----- Original Message -----=20 From: Kevin E. Ramsey=20 To: Pianotech=20 Sent: Friday, January 24, 2003 8:27 PM Subject: Re: Capo Hardening, was: Tuning problems under capo bar Hello Ron. I there anything you can tell us about hardening the = capo. I've seen you write about that before. Is this something you do in = your shop? Do you do it to all pianos? Do you have a method of testing = the hardness of the capo? Am I asking questions that have already been = answered? Thanks.=20 Terry Farrell=20 Terry, I don't know about Ron, but I've thought about it, and I = don't see how you could harden the capo. I hope I'm wrong, but you hard, = or temper a metal by heating it until it glows for a certain amount of = time, and then you quench it in either oil or water. The plate is going = to act as a gigantic heat sink, not allowing the metal to get to the = proper temp, and you'd have trouble quenching it even if you did. When = you heat a metal and allow it to cool by itself, it's called annealing, = and it softens the metal. Others can tell me if I'm all wet, but that's = how I understand it.=20 Kevin E. Ramsey ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/db/c9/32/45/attachment.htm ---------------------- multipart/alternative attachment--
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