> > Key Ratio taken Stanwood style is done with the key level. So distance > measuring along the top of the key instead of the way its usually done > (top front down to balance rail at the pin and up again to the capstan) > gives the same results as in the horizontal position all weight values are > vertical forces. Course this changes when you move the key, but thats the > same in anycase. If you measure distances the usual way, you may find a > slight difference... or not.. but you have to be sure your measurements > are very very accurate. 1/ 1.83 = 0.54~ btw. **** Will work on remeasuring the horizontal method - seems much easier. Never dreamed that 1/measured ratio would equal KR - makes sense now. A great cross check on work progress. > As long as the stack is aligned correctly over a straight line of capstans > all yielding the same KR, and the heals all the same distance from their > respective flange centers, there will be no difference in effective WW. > For any key with a 0.5 ratio, a distance of 10 mm movment at the front > will result in a 5 mm movement in the opposite direction at the capstan so > whippen travel will remain constant. ***** Right now, the only thing on the action that is paralell to the whippen rail is the hammer rail and maybe the back rail. Capstan line is different in bass and treble by 3mm in relation to the whippen rail - but the line is straight. Balance rail is also different. It makes sense that the constant KR - regardless of the overall key length - would yield a constant rise at the capstan but if the whippen heals are aligned to the whippen rail they will differ slightly in alignment with the capstans by 3mm across the action - changing WW. Am I reading too much into this? > Seems to me if you can find an acceptable way of increasing leverage then > you should do so to get into usual ball park figure for key dip and blow. > THEN re-address your BW by adding what looks to be moderate levels of key > leading. **** I believe that I will solve geometry by decreasing action spread by 2mm from 113 to 111 - this will give me adaquate blow distance. Then I will move the capstans back by 3mm - this will give back most of the leverage that will be lost by shortening spread and allow the whippen heals will completely cover the capstans. Thank you so much for your help and insights - I have learned a great deal. Gene > Cheers > RicB > > Hello Ric, > > Back with just a bit of data: > > Moving the whippen heals as close to the whippen flange as possible > (about 3mm) gave considerable more hammer travel for the 10.5mm key > dip that I did not change. Blow increased from 41 to 47mm. The > expense was an increase in balance weight from around 40 to around > 44. I changed the action spread just to see what would happen, > reducing it from 113mm to 112 mm and the effect was similar to the > above. The bonus was that the knuckle jack alignment improved. Put > back to 113 at end of day.Now the capstan whippen heal interface > puts the capstan at the extreme edge of the whippen heal - > especially in the treble. I had hoped to move the capstans closer to > the balance rail by 3mm but not with these whippen heals in this new > position.Put everything back like it was and the 41mm blow distance > returns. Basically this was nothing more than centering the whippen > heals on the capstans. > > It is curious to me that the measured key ratio and the weighted KR > of notes #1 and #88 are the same at 1.83 in mm and .54 in grams. > However, the key sticks differ in length by 10mm, and the key > capstans also taper bass to treble only not as much - more like 3mm. > Example: key front to balance rail #1 = 232 mm and #88 = 222mm Balance > rail to capstan #1 = 127mm and #88 = 121mm In either case > the weighted and measured ratios appear to compare but the key > length and taper of the capstan line are not obvious unless you > measure or try to decide how to position the whippen heal to the > capstan. A clear need for measuring. In addition, #1 has 3 leads and > #88 none - measuring cannot detect this. Another puzzle to solve is > positioning the whippen heal to the capstan. As the capstan line > tapers, should the whippen heal line also taper to match the > capstans? This would change the WW value?? Or keep the whippen > heals a fixed distance from the flange center pin?? This would > effect whippen travel?? Confused. Thanks for taking an interest. > Gene > > >
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