Thanks for the numbers Gene. Well, you do have a bit of a high ratio... (low leverage as Jon puts it). Tho its not way up there by any means, except for note 88 which spikes much higher then the rest. Still you are about 6.1 it looks like, which is consistent with everything except the blow and dip. This got David Love scratching his head as well I see. Somethings amiss to be sure. A 6.1 Balance weight ratio that requires 41 mm blow and 10.5 mm dip to get minimum aftertouch. A few thoughts: -If you are going to increase your blow distance and keep the key dip the same... or even (preferably) allow for a shallower key dip setting if desirable, then you are going to have to increase leverage. (Which should be high enough already for that goal... but set that aside for the moment) -Your Front weights are reasonably light all the way. So you can increase them somewhat to compensate to maintain your desired BW. - Moving to a 17 mm knuckle would give you a good increase in leverage, I agree with John that moving the capstans further out is probably not a good idea.... tho I have run into as high as 0.6 KR (you wrote it the other way... and that would be 1.66) A larger knuckle, as Jon says, may also be a good idea if the ones you have are small and/or worn.... didnt catch if you are using new shanks here. This said... as both David and Jon echo, it looks like something isn't quite right. You seem sure of your measurements so, the next thing to check is your lines of centers. David mentioned this and I'd agree. You may have a geometry problem of some sort... Jon mentioned Bob Hohfs article and the possibility of changing the stack height... the spread you give seems reasonable, but you want to take a look at the jack angle at the rest position and capstan / whippen cushion intersect with their line of centers at half blow at least. To answer your direct question. It is my opinion that a blow distance of 41 mm is a bit to low. Gives you no room at all to change touch characteristics... especially with deep key dip already, and it will limit power more then I would want. What to do depends on whats causing the inconsistency mentioned by all three of us. If you like the touch as it is, and are only worried about the short blow / deep key dip (and I would definitely want to know the reason for that in this case myself) then I suppose you could live with things... but I'd be skeptical myself. That blow/key dip doesn't add up with a high action ratio. Interesting side point.... this kind of reveals a major type flaw in the idea of relying on simple distance ratio measurements to establish the ratio. Jons initial guess (as I interpreted it) took for granted a low ratio instead of the high ratio we are looking at.... tempting to do when you just hear the key-dip /blow numbers. Dale hopped on that with both feet... and he's stated several times he just measures key movement for hammer movement to get his action ratio. Seems on the surface of it to show what many of us have felt for a long time now. Stanwoods approach to measuring the ratio is a superior diagnostic tool for analyzing an action. Cheers RicB ******My samples were not all C's but they are all naturals, first and last in each section. - here it is: note# SW FW BW KR WW 1 10 30.1 41.5 .55 16.4 25 10 26.7 42.5 .52 16.4 27 9.3 23.8 39.5 .54 16.4 45 8.4 15.5 44 .54 16.4 47 8.7 16.6 42.5 .53 16.4 66 6.8 7.7 42.5 .54 16.4 68 6.5 6.5 41.5 .54 16.4 88 5.0 6.8 36.5 .53 16.4 Note that the WW value is the same because it is the average - the range was from 15.9 to 17.2
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