Working again with note #40, I moved the knuckle way out to 18 mm and then back to 17 mm. I moved the wippen rail out 1.5 mm for an action spread of 115 mm - that made the jack/knuckle-core alignment very good. I was able to remove more lead from the key. Here's what I have now: Action Ratio: 5.7 FW: 16.1g (0.54 of Stanwood's maximum FW of 30.0g for note #40) KR: 5.2 DW: 50g UW: 32g BW: 41g SW: 9.1g F: 9.0g Knuckle-Core distance: 17 mm Action Spread: 115 mm It appears all will regulate very nicely. I didn't measure blow and dip accurately at the time of this post. Couple questions though. Action ratio is in the "normal" ballpark, although perhaps not optimal for this action? FW is way low for key #40, however, I have something in the range of a "good" amount of lead - see picture below: DW is nice - right where one would want it. UW is high - but is that bad? Does the key ever return too fast for a pianist? But why is it so high? I know that you don't get something for no price. Doesn't that suggest that the action is suffering somewhere else? BW is high. So? As another person asked: What does BW mean to or do to a pianist? What does it matter? What does it mean (I know the definition) from a practical standpoint? David Love - what makes you say that you like a 37g BW - is it because 37g BW "feels good" to you - or that you can't "feel" BW, but rather when you have a BW of 37 the other parameters usually are near their optimum? SW is right where David Love suggested - I extrapolated by simply following the Stanwood Smart Chart curve from his SW recommendations on notes #20 and #1. A 9.1g SW is just a hair below the exact middle of Stanwood's SW curves - so this is a medium SW. It seems to me I am getting closer to where I want to be. Good leading (key inertia), hammer weight and Down Weight. Seem like the only thing concerning me is my high Up Weight and Balance Weight. Are these a real concern? Why/how would the action perform better if I were able to get BW down to 37g (or there abouts) and reduce UW to 25g or so - all, or course, without changing leading, SW and DW? Seems to me the only way to potentially do that would be changing the action ratio - but how - capstan, wip rail, knuckle? And I still have the nagging question about key lead on this action: Why do I have such a very low FW, yet a "normal" amount of lead? This also has me scratching my head and worrying that something is horribly amiss elsewhere - again, the little bit I think I know about action balancing is that everything is a compromise - you don't get anything for free - the only way to pay Peter is to take from Paul. Man, when does it end? :-0 Thanks for all the input. Terry Farrell ----- Original Message ----- I meant a 9 gram hammer weight. Strike weight would be plus the shank. At note 1 I am generally in the 9 - 9.5 grams hammer weight. Add 1.8 grams to get the strike weight on average with a Renner shank. Your 10 gram hammer producing a 11.9 SW at note 16 is easily a full gram higher than I would normally go. SNIP David Love Original Action Parameters: Action Ratio: 5.67 FW: 36.25 (0.966 of Stanwood's maximum FWs) KR: 5.1 DW: 50g UW: 27g BW: 38.5g F: 11.5g SW: 11.9g Blow: 48mm (1-7/8") Dip: 9.85mm (0.39") -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20070707/c3cd2f00/attachment-0001.html -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: image/jpeg Size: 32864 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/20070707/c3cd2f00/attachment-0001.jpe
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