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Adjusting WNG Rep Lever Height

  • 1.  Adjusting WNG Rep Lever Height

    Posted 01-20-2019 19:59
    Edited by Jim Ialeggio 01-20-2019 20:04
    On WNG wippens, I had been  having trouble adjusting rep lever height.  The problem being, that the way I adjust rep lever height on wooden actions, winking the jack, was just giving me too ambiguous a reading. When adjusting wooden wipps, after adjusting jack position, when winking the jack, an at rest hammer will drop as the jack is winked, and then return to the full at rest position when the jack is allowed to reset. With the WNG wipps, the hammer would not return to the previous at rest position. It was driving me nuts. Hammer lines were of course inconsistent. Where the hammer would come to rest was behaving oddly and randomly...usually an indication of a spring problem.

    So, what I realized was, that because the winking was giving me untrustworthy info, the regulating button on the rep lever was never completely coming to rest on the felt glued on the wippen body at reset. Instead, it was hanging up in mid air, not contacting the wippen body felt. It wasn't a spring issue or a spring tension issue, as I originally thought, and experimented with. Instead, I realized that this is symptomatic of the rep lever and jack tip not sharing the hammer weight in the proper equilibrium...ie rep lever height. My winking was giving me bogus information. Getting this adjustment right and consistent fixed the problem.  I made a video showing my technique, which I really like. I have not tried it on wooden actions yet, but will as soon as the opportunity presents itself.

    Its easier to see what I did than to explain it...embedded video attached.




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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 2.  RE: Adjusting WNG Rep Lever Height

    Posted 01-20-2019 20:59
    Jim -
    Nice video, but it would have been better if you would have demonstrated the non-wink / wink aspect of the problem.
    You say that it isn't a spring strength issue.  How did you experiment with that?  You must have been able to increase the spring to where it would hold the hammer without the jack.

    While at it, what was the rep-lever pinning friction?  hammer pinning?

    Your method seems effective but doesn't explain the cause.

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    David Skolnik [RPT]
    Hastings-on-Hudson NY
    914-231-7565
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  • 3.  RE: Adjusting WNG Rep Lever Height

    Posted 01-20-2019 22:11
    <the non-wink / wink aspect of the problem.

    This is interesting. Prior to coming up with this, I could not find the position where the wink would drop and reset to the exact original rest position. After I came up with this technique I could find it. The difference is, was, I think, that when I would wink with wood actions, I would look for an almost imperceptible wink. On these wips, the drop and reset must be more obvious than almost imperceptible. On the video I did wink an adjusted rep lever, and as you can see, the wink movement is more than almost imperceptible.

    I wondered if this would effect repetition. But it does not seem to...the reason being that the technique I showed, finds, empirically, the equilibrium point where bearing on the jack and lever is balanced. Any less movement in the wink, would have either the rep hanging in mid air again, or jack taking too much weight challenging jack full return to rest

    The springs do seem to behave oddly on these wips. Rep lever pinning out of the box is a strong 7g. I reduced pinning to 3-4g, as I don't buy the tight pinning argument on the rep lever. Hammers, I go for 4g these days,  4 max, some 3's, and a few 2gs, but mostly 4g. Increasing the spring strength to test by exaggeration did not change the wink reset behavior. I think it has to do with the design of the spring and the grub contact on the rep lever itself...it may be a high friction spring/grub interface, but I don't know.

    That said, this is the only thing that bugs, or I should say bugged me about these parts...and its a very fine point. The hard bushings, and the highly adjustable heel heights and positions are major big bang advantages, because I can nail my leverages right on the money every time, with stress free control. Repetition, for an Erard/herz style wip is good...not perfect but pretty good. But that's the case with any Erard/Herz wip.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 4.  RE: Adjusting WNG Rep Lever Height

    Posted 01-20-2019 22:31
    I should add to what I said about looking for an almost imperceptible movement in the hammer when winking wooden actions, that I am not sure looking for that minimal amount of hammer movement is correct. I'm not making a statement here, but rather raising a question.

    Frankly I have always found this adjustment to be ambiguous, even with wooden actions, but never looked at the other end of the rep lever to see what it was up to regarding rep lever height.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 5.  RE: Adjusting WNG Rep Lever Height

    Posted 01-21-2019 01:19
    This is why I have learned to really dislike the "new" PTG Pianotech. Obviously some of you have managed to view Jim's video. I cannot find it anywhere. 

    Surely we can do better than this. 

    ddf

    --
    Delwin D Fandrich
    Fandrich Piano Company, Inc.
    Piano Design and Manufacturing Consulting Services -- Worldwide
    6939 Foothill Ct SW -- Olympia, WA 98512 -- USA
    Phone 360.515.0119 -- Mobile 360.388.6525





  • 6.  RE: Adjusting WNG Rep Lever Height

    Posted 01-21-2019 08:04
    https://youtu.be/R984Ck3LxpE

    try this Del

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
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  • 7.  RE: Adjusting WNG Rep Lever Height

    Posted 01-20-2019 21:23
    Jim,
    I think it's a brilliant observation. Can't wait to play with that tomorrow.
    -chris

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    Just Looking through the Go-Bars
    chernobieffpiano.com
    grandpianoman@protonmail.com
    Knoxville, TN
    865-986-7720
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  • 8.  RE: Adjusting WNG Rep Lever Height

    Posted 01-20-2019 22:13
    I'm interested to see what you find, Chris.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 9.  RE: Adjusting WNG Rep Lever Height

    Posted 01-21-2019 00:17
    I have never used the W,N&G whips. But I wonder if some of the winking problem is due to friction between rep spring and rep lever groove and/or jack to spring interference where they touch. I know some NY reps had problems with setting rep levers via winking where the spring touched the jack that would cause some binding until the spring shape was changed to eliminate the binding.

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    Edward McMorrow
    Edmonds WA
    425-299-3431
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  • 10.  RE: Adjusting WNG Rep Lever Height

    Posted 01-21-2019 08:17
    Ed, I do see a fair amount of spring distortion, on the jack side of the spring on compression. I have not looked carefully at the dynamic behavior of vanilla wipps.

    However, to repeat what I said earlier, in the big picture, since the rest of the design is so friendly to achieving my leverage targets, and the hard bushings are such a relief, compared to reverse pinned or unstable felt bushings in new parts of all other wooden manufacturers, having this technique reduces the spring difference to a minor issue.

    Said another way, I don't buy wooden wipps anymore, because in other ways, compared to the composite parts, they are a major pain in the ass.  Actually, these days, when the old wipps are not dried out and ready to crack on the rail, I often rebuild wipps, especially if they are the excellent Chickering, really low spring friction design. I always use the shanks, though...always.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 11.  RE: Adjusting WNG Rep Lever Height

    Posted 01-21-2019 10:50
    Jim -
    Whether on list thread or a new one, I'd be curious to hear why you don't buy into the firmer-pinning theory re: rep levers.  Obviously, it can be overdone, but most current production has them around 2 gms.  Why would you think that to be preferable?

    Regarding the spring, the only problems I ever observed on the jack-end were either that the inserted tail was too long and actually contacted the back side of the 'observation-window', thus impeding the movement.  The other was an incorrectly bent tail that either exerted the wrong pressure or interfered with the slight sliding motion of the spring in the jack hole.
    I don't believe that spring friction has anything to do with the problem you're observing, though, in older, worn actions it can play a role.  One interesting comparison (again, having nothing to do with the topic problem) between WNG, Renner (with spring-screw adj), and NY has the Renner as the odd-man out, in that the point of contact between spring and rep lever moves distally (away from jack) as opposed to the WNG and non-screw-adjust, which has the contact point moving forward, towards jack.

    More to the point is the manifestation of the same symptoms in the early Renner USA parts, which I don't think I ever gained any good will for pointing out (but who remembers, or cares?).  At first I thought it had something to do with the lower friction of the spring contact but, with younger eyes, I zeroed in on a discrepancy between the profile of the arms of the rep lever and the radius described by the travel of the top of the jack, which was the smaller of the two.  As soon as jack displaced from its rest position, the top dropped below the level of the rep arms, losing all contact with knuckle, thus, no winky.  By the time it was regulated to display said wink, jack had trouble returning to position.

    Examining WNG parts as carefully as I can, I don't think this is the problem... only that the symptoms were similar.  Observing the video, I don't try for that degree of wink even using wood parts.  I mostly feel for the friction of the jack/knuckle contact and look for the slightest of displacements but your technique will certainly be a useful check.
    Thanks


    ------------------------------
    David Skolnik [RPT]
    Hastings-on-Hudson NY
    914-231-7565
    ------------------------------



  • 12.  RE: Adjusting WNG Rep Lever Height

    Posted 01-21-2019 20:05
    Edited by Jim Ialeggio 01-21-2019 20:36
    David,
    I get that you think my video wink showed is too much movement. I too thought that much wink movement would impede jack return under the knuckle. However, after I stared at this for some time, in real-time experimentation, I found no empirical evidence of the jack having an issue on the return, in actual dynamic play. That made me wonder about the my previous assumptions about what is actually happening in this jack tip/knuckle interface...It led me to question what the wink claims to be doing.

    It is always presented that the jack has to be able to slip under the knuckle at rest. However something about this visual model, and the wink, has never sat well in my mind...but I didn't pursue it.

    In thinking about this since my post yesterday, some things have begun to clarify, regarding the wink . Actually...now don't throw things in the direction of Shirley...but I think the wink is actually an entirely inappropriate test. It is testing whether a hammer will wink, but in dynamic play, there is no part of the stroke where a wink scenario actually occurs...I don't think.

    Lets take the jack/rep lever/knuckle interaction step-by-step through the stroke and repeated stroke;   In dynamic play..

    1- At rest, the jack and lever share weight, in some unknown proportion. My guess is that it is just enough so there is no free play, whatever proportion that is.
    2-The stroke starts... jack is the sole power vector, and thus the support vector, until letoff. Relationship of rep lever to jack of no consequence, as the jack is in complete control.
    3- At letoff, hammer escapes away from the jack and rep lever. No contact with the rep lever or jack. So, Relationship of rep lever to jack still of no consequence.
    4-Hammer rebounds from string in the initial stroke.  Rebound is somewhat tempered by the lever, but the check takes over complete control of the hammer and thus the rep lever almost instantly, even in fast repetition. There is no jack involvement or return here, as key in dip is holding jack in the escaped position. Relationship of rep lever to jack still of no consequence.
    5-Key released, simultaneously releasing the check. Jack resets, as the rep lever raises the hammer instantly out of check...rep lever is moving away from the jack, allowing plenty of clearance for the jack to reset. No opportunity for a mis-adjusted rep lever to impede jack return. Relationship of rep lever to jack still of no consequence.
    6-Next stroke or repetition starts, with jack sole power vector again. Relationship of rep lever to jack still of no consequence, because jack has complete control again.

    1-6 has just taken us through an entire cycle into the next stroke. At no point could the rep lever height/knuckle impede the jack reset.

    If the reset does not go into a repetition, but just lets the hammer rest until the next time it is needed, the rep lever is raising the knuckle away from the jack as it resets to rest. So, relationship of rep lever to jack still of no consequence.

    I see no point in this analysis that a mis-adjusted rep lever can impede jack reset, in dynamic play!

    My hypothesis is that rep lever height's function is only critical to avoid lost motion for the initial stroke. The rep lever has a practical function in repetition, but not in any position where jack return can be impeded by the knuckle. Even when testing for jack reset, which we do with the hammer at rest is meaningless. This, because in dynamic play, the jack never resets when the hammer is motionless in the rest position.

    Intuitively, I think this is the reason I went with finding the point of equilibrium between jack and lever the way I did. Equilibirium, empirically proven, means the interaction is as "ideal" a no-lost-motion position as is physically possible, given the parameters of that  complete as-built system.

    So, where does the wink come from??? Where in that stroke does any physical relationship of rep lever to jack tip occur that resembles the wink position???  My contention is nowhere. The wink position is proving that the parts can wink, but it is proving nothing else of practical utility.



    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 13.  RE: Adjusting WNG Rep Lever Height

    Posted 01-21-2019 21:28
    Edited by Jon Page 01-21-2019 21:29
    In Hi-speed video, the rep spring does not lift the hammer, it aids in pressing the rear of the key back down. The tension of the spring is regulated using the speed of the hammer's rise on check-in release. The 'wink' is to locate the rep lever height whereby the rear edge of the jack glances against the knuckle. If the friction of the hammer and rep lever centers is too low, the spring tension is lowered so as not to produce a jump in the hammer and the end of the rep lever impacting against the upstop screw.  Once higher friction is reestablished in the centers, the spring tension will increase and will support the weight of the hammer when the jack is tripped out.

    I'll bet that the rear of the rep lever stayed up because of the low spring tension, hence the traditional 'wink' was not adequate.  I don't think 1-3 gr friction on hammer and rep centers is adequate. I've proven it to myself and have repinned entire actions. Problems solved. Just because they are the latest wizz-bang parts doesn't mean that time honored parameters should be abandoned.

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    Regards,

    Jon Page
    mailto:jonpage@pianocapecod.com
    http://www.pianocapecod.com
    ------------------------------


  • 14.  RE: Adjusting WNG Rep Lever Height

    Posted 01-21-2019 21:40
    <I'll bet that the rear of the rep lever stayed up because of the low spring tension, hence the traditional 'wink' was not adequate.

    Nope. tested that by exaggeration, increasing the spring tension to ridiculous levels...no difference in the wink. I think its the spring design.

    Hammer friction mostly 4g, with a few outliers at 2g

    Rep friction at 7g+ tends to challenge soft blow check...its all a dance. I have used the  7g. In addition to challenging soft check, it increases the resistance at letoff, which, for me is a major major no-no. My idea of the mark of a really fine action feel starts with a crisp but gentle letoff. The high spring tension/high friction rep lever challenges two parameters for me which are two of my no compromise priorities.

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    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 15.  RE: Adjusting WNG Rep Lever Height

    Posted 01-22-2019 08:28
    Whatever the science, your method is very similar (if not functionally the same) as one that Chris Robinson demonstrated many years ago holding down the keys with one hand and lightly dropping the hammers down whilst observing the movement of the opposite end of the rep lever (where you are tapping) and making adjustment till no more movement is observed. He claimed this is done in the factory because it is faster and more accurate than winking.

    This is a "in a nutshell" description but the principle is identical (as I see it).

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
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  • 16.  RE: Adjusting WNG Rep Lever Height

    Posted 01-22-2019 12:33
    Interesting. Not identical tough, but very interesting.  In the procedure you describe, Peter, you are taking the jack completely out of the picture. In my thinking, with my technique, the jack was taking most of the weight...but maybe not. Have to play with this technique.

    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 17.  RE: Adjusting WNG Rep Lever Height

    Posted 01-22-2019 12:41
    Edited by John Rhodes 01-22-2019 13:58
    Peter, "...holding down the keys..."  This means holding down the key *tail*, right?
    That adjustment criteria would insure 100% of the hammer weight is born by the jack -- not shared with the rep lever.

    I like that criteria for new/factory parts, but for well-worn ("experienced") parts -- where the jack may have made a divot in the knuckle -- I'd follow with a check to be sure the jack will fully reset when "winked".

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    John Rhodes
    Vancouver WA
    360-721-0728
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  • 18.  RE: Adjusting WNG Rep Lever Height

    Posted 01-22-2019 14:42
    John,

    Yes, totally...the back of the keys. And yes, does not work well for worn parts, just new. Also, I would say primarily to find the worst ones very quickly and get them close. I am not going to say that it is a fine adjustment except with significant experience on the same parts daily. But the principle appears to be the same.

    Pwg

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    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------