I have no scientific research to bring to the table here but only observation. I believe inertia has a big effect on the feel of an action. More, perhaps, than we usually think of when setting one up. Fortunately the start-up key inertia has been overcome by the time the key engages the damper lever. Remember that inertia is the tendency of a body at rest to stay at rest, and the tendency of a body in motion to stay in motion. Once you get the key moving, that moving inertia helps to start the damper lever. In most well designed and regulated actions you don't notice the damper lever being lifted because the key's motion inertia helps to overcome the damper levers rest inertial. If you have key weight of 45 grams and damper weight of 25 grams at some point in the key travel you increase the load by over 50%. Only the inertia of the key overcoming the inertia of the damper lever could explain your not noticing this additional load. dave David M. Porritt dporritt@smu.edu -----Original Message----- From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On Behalf Of V T Sent: Friday, March 25, 2005 8:04 PM To: pianotech@ptg.org Subject: Under lever gram resistance Hello Dave, List, >What's the difference whether the effective weight of >the underlever is due to lead weights or spring >tension? That is a very interesting question. The main thing that comes to mind is inertia. The heavily leaded damper would in theory take longer to accelerate, and it would also add some heaviness to the key when playing fast/loud. How significant is this in practice...? Many of us subscribe to Stanwood's method of controlling weight within a narrow window, but I never hear much about the effect of the damper system. Has anybody on the list made some interesting discoveries about the inertia of the damper system? Vladan __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ pianotech list info: https://www.moypiano.com/resources/#archives
This PTG archive page provided courtesy of Moy Piano Service, LLC