Today I started repositioning capstans and whippen cushions on sample keys on the Duysen grand action I am redoing. The results are quite dramatic to be sure. After checking, rechecking, measuring, re-reading material, consulting with a couple guys off list, and then double checking again... I decided it was time to actually start the work. In short, the whippen cushion is now 9 mm forward of its origional position and it is longer by 5 mm. The capstan is moved 12 mm forward. I figured the angle for the capstan by marking a line on the key perpendicular to the whippen post when the key was at half dip. The difference in movement lengths (capstand and cushion) are due to the fact that the action spread has also been moved inwards about 3 mm to line the jack center and knuckle up correctly. Origionaly I had a whippen balance weight of around 11.4 grams composed of a key ratio of 0.6 , and a whippen radius weight of 19. The move of cushion and capstan results in a key ratio of 0.56 and a whippen radius weight of 17.1 resulting in a whippen balance weight of 9.6. The origional Up / Down weights were 69 and 39 respectively for key number 1 and with the origional assist spring tension (at quite strong) these were reduced to 48 / 29 respectively. Gone is that clunky heavy feeling completely. Fooling a bit around with the assist spring just for fun I could easily adjust touch weight without returning to a clunky feeling touch. The existing front weights are way under ceilings for a 9.0 whippen balance weight so I should have plenty of room for adjusting these both ways when I decide on a Balance Weight and start weighing off. The contact between the whippen and the capstan is now dead on the magic line and friction at this point is as low as I can get it with my present level of proficiency. This was great fun I have to tell you. In the next days I will be marking the points for the new cushions on all whippens, new capstan points and drilling. Then I have to wait for the parts to arrive. Grin... having a ball.. Have learned lots, expect to learn lots more before I am done with this one, and see extreme potential with all of this. -- Richard Brekne RPT, N.P.T.F. Bergen, Norway
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