Phil Bondi and I dove into an 1890s WNG action from a 6' 4" Knabe today to try and straighten out some basic action geometry. We haven't got all the kinks worked out yet, but we seem to be getting there. With only a large capstan move and removal of a couple leads, we went from an action ratio of over 6.0 down to 4.9. DWs went from 60+ to 50 and less (I know, too light) and BW in the 36 to 40g range. We have a lot of work to do yet, but it seems the capstan move described below has gotten us into the right ball park anyway. Most notable was a very large capstan move that we will likely keep (unless someone so kindly informs us of a potential problem the change might induce). The photo below shows the original capstan in the background. The forward key had its capstan moved 10mm forward and 11mm lower. The middle key had its capstan moved 13mm forward and 12mm lower. The second photo shows the modified wippen heel. These lower positions put the capstan right on the magic line at half blow. The capstan/wippen heel interface went from a traveling, grinding, sliding affair and a note with 17g friction to a perfectly interfacing union with no apparent sliding and a note with 9g friction. We were amazed at the improvement in friction and interface movement. This strikes me as a rather drastic capstan move. Has anyone else run across an action that needed such a large capstan move? As our action ratio is down to 4.9 and key ratio is down around 4.8 with the 10mm forward capstan migration, we may move it back just a few millimeters. But still it seems large. Is there some hidden pitfall I'm not seeing? Comments? Terry Farrell -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20060717/28582c8c/attachment-0001.html -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/jpeg Size: 46994 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/20060717/28582c8c/attachment-0002.jpe -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/jpeg Size: 42405 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/20060717/28582c8c/attachment-0003.jpe
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