At 5:36 pm -0800 14/2/07, Jurgen Goering wrote: >John, I am aware of the velum sold by BG. and others in Germany. >Regardless of what the dealers may say, it is too thick and too >stiff for Blüthner back actions and other action applications in >vintage instruments. The sellers are, by and large, not piano >restorers and do not speak from experience. 0.3 and 0.7 mm velum is >fine for harpsichord rosettes. For the purposes we are talking >about, the velum should be no thicker than 0.15 mm, otherwise the >damper underlevers tend to float just a little. I have this >information from an experienced tech in Germany who has written an >article on replacing the Blüthner back action velum hinges. Jürgen, I have now collected and dismantled the Blüthner damper action. Here is a picture of one of the bodies. I will report in more detail later, but the vellum (dry) on this action is almost exactly 0.5mm thick. I will measure the slots when I have removed the hinges and everything is dry. I would agree that such a vellum might be too thick for the hinges on early squares etc. but for grand damper bodies it is fine. JD -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20070217/4590fb07/attachment-0001.html -------------- next part -------------- A non-text attachment was scrubbed... Name: P3FFC4791.png Type: image/png Size: 73472 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/20070217/4590fb07/attachment-0001.png
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