At 8:48 pm -0500 22/8/07, William R. Monroe wrote: >How long do you find you need to leave the dampers clamped for this >"winged profile" to hold? Have you ever had problems with the >dampers not retaining the profile? It depends on the temperature and the air circulation, but I might leave the strip in the screw clamp for two or three hours and then transfer it to the simpler clamp <http://pianomaker.co.uk/damper_pictures/dampers_1.jpg> after applying the backing cloth and leave it there another few hours. This second clamp is a simple board of mahogany with a straightened clock-spring set into it, and for most pianos, which don't require the bump at the top shown in the illustration, I just use a single top lath and 10 Pony clamps. It's all pretty primitive but it works. As to the felt's retaining the profile, so long as the PVA glue has passed the rubbery stage, the profile will first open op just a bit and then hold. If you underdo the clamping and the felt begins to flatten out, you just clamp it for a bit longer. The thing to avoid is leaving it in the clamp until the glue is thoroughly set, because then you get too pronounced a V. I'll be doing the dampers on a Bechstein Model C grand this week and will take some more pictures. JD
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