<HTML>List, For a change of subject, I received this private e-mail from some unknow= n person.  It concerns the accelerating effect that heat had on the= notorious plastic elbows found in the darling Betsy Ross spinet.  = Believe it or not, I had a customer who really wanted one of those piano= s.  I searced for a long time for one and after a couple of years, = found one for him and earned very handsome fees for the reconditioning, = which included the replacement of all the plastic elbows, setup and inst= allation of a complete Dampp-Chaser system. People have their opinions about pianos which they consider not to even = be pianos and about Dampp-Chaser products too.  All I ever see in e= ither one is $$$. Bill Bremmer RPT Madison, Wisconsin << http://www.ptg.org/archive/pianotech.php/1999/v1997.n1793 ` Since someone was kind enough to archive piano info for me, I h= ave to tell you, you are right about Damp Chaser and other dehumidifiers damaging things. You probably know more than I about the effects of very low humidity on woods but for wood AND plastic or anything else, heat is the enemy. Virtually all chemical reactions, including oxidation of plastics, happen faster at higher temperatures and, conversely, slower at lower temps. 10-20 year aging tests are done in much less time, at higher temps because this relationship is pretty accurately known. Exclude oxygen to prevent oxidation... I often close a can of varnish etc. after flushing it with a snork of propane from an unlit torch, then momentarily invert it to seal the lid... Store your treasures in a cold dry nitrogen atmosphere in the dark (no UV) and they'll last a gazillion years (technical term). Roy >> Thanks for your comment.  I believe that a complete humidity contro= l system benefits all pianos, I have one in my own and depend on it to k= eep my piano in tune.  The customers I have with them have pianos w= hich do remarkably well.  However, I had noticed over the years tha= t many Betsy Ross spinets had a single, uncontrolled dehumidifier rod. &= nbsp;These pianos had those notorious plastic elbows.  Sometimes, p= eople left the dehumidifier plugged in at all times.  I can easily = see how this greatly accelerated the breakdown of the material in those = plastic elbows.  I'll never forget the piano which had elbows that = crumbled in the fingers like Christmas candy. Regards, Bill Bremmer RPT Madison, Wisconsin </HTML>