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12 heavy notes

  • 1.  12 heavy notes

    Posted 07-05-2018 20:55


    I am seeking help solving a problem.  The piano is a 1988 Baldwin L.  I did some action work; new hammers, shanks, replaced the key bushings and regulated.  It was all pretty straight forward.

    Before I did any work I measured all the down weights and up weights.  Most of the down weights were between 58 and 61 and up weights were in the normal range.  Although I thought it was a little bit heavy  the client liked the way the action played and did not want to change that. 

    With the work that has been done so far the down weights and up weights are almost exactly the same, except on 12 notes.  There are 12 notes that have down weights between 68 and 70 grams.  They are mostly in the low bass but also 2 in the low tenor.

    I cannot find any friction problem or any reason for these 12 notes to be different, and play so much heavier than the others.  The key bushings are free, they are not rubbing on their neighbors.  Key pins and capstans were polished and then I applied teflon powder.  Knuckles and whippens heels also burnished with teflon power.

    I'm supposed to return it Monday, but I can't bring it back with 12 notes so radically different from the others.

    I've trying to figure this out and so far have not been successful.


    David Weiss

  • 2.  RE: 12 heavy notes

    Posted 07-05-2018 21:06
    Are the hammer wieghts matched to the old hammers. Heavier bass hammers will do this.

    Jim Ialeggio
    Shirley, MA
    978 425-9026

  • 3.  RE: 12 heavy notes

    Posted 07-05-2018 21:18
    Process of elimination, if you have the old hammers  for that 12 note section, pop one of the new ones off and dry fit an old one and re weigh, also  check the pinning on the new shanks just coz they're new don't mean its right! Also what's the humidity right now in VA?

    Martin Snow
    Boston MA

  • 4.  RE: 12 heavy notes

    Posted 07-06-2018 05:33
    Jim the hammer weights are almost exactly the same or even slightly lower.  

    Martin:  Process of elimination.  I asked myself what has changed?  What has changed is new hammers and shanks, new key bushings, and regulation.  The regulation was straight forward with no  radical changes, so that is not the cause.  The new hammers have the same or slightly lower weight, that is not the cause.  The new shanks are not heavier than the old ones, the knuckle size and diameter is also the same.

    The wippens have not changed.  The pinning of hammer flanges is perfect.

    To my thinking the key bushings are the only thing left in the equation.  But the fit of the new bushings is excellent.  All of the new key bushing felt has been burnished with Teflon powder and the key pins polished and sprayed with Teflon spray.

    Here's an example of a quick experiment I did at 3 am since I was awake thinking about this.  Note C1 had a down weight of 61 grams with the old parts.  With the new parts the down weight is 70, but the new hammer is .3 grams lighter than the old one.

  • 5.  RE: 12 heavy notes

    Posted 07-06-2018 11:41
    A shot in the dark. Have you examined the concaving of the whippen cushion? Some years ago I experimented with Teflon on the capstan/whippen cushion contact point. Simply adding Teflon didn't decrease the amount of friction much, if at all. What I did find was that bolstering the whippen cushion decreased down weight dramatically. A deeply concaved whippen cushion may not show up as a high friction point but the misaligned balance/capstan/whippen flange line is enough to cause the action to go into action dampening, i.e. as the key is depressed the leverage ratio decreases, i.e. for every given moment of the downward key movement the wippen increasingly moves less and less. That may give you a heavy feel.

  • 6.  RE: 12 heavy notes

    Posted 07-06-2018 11:56

    I've used VS Profelt for this on the wippen cushions, and yes, it does help lower the DW a bit.



  • 7.  RE: 12 heavy notes

    Posted 07-06-2018 11:59
    As someone previously suggested, I would next check the balance rail mortices.  This source of friction can make a big difference to the feel of the key but is so often overlooked.


    Christopher D. Purdy R.P.T.
    Registered Piano Technician
    School of Music, Ohio University
    Rm. 311, Robt. Glidden Hall
    Athens, OH  45701
    Office (740) 593-4230
    Cell    (740) 590-3842
    fax      (740) 593-1429

  • 8.  RE: 12 heavy notes

    Posted 07-07-2018 09:16

    Also check the balance rail hole at the bottom of the key.  You should be able to slightly lift the key and it should fall down easily.

  • 9.  RE: 12 heavy notes

    Posted 07-06-2018 05:55
    Lots of speculation, but no usable data. What were the up and down weights before and after of the keys of concern? With the scant information provided, we can't even tell whether it is a friction issue or a balance weight issue.

    Terry Farrell
    Farrell Piano Service, Inc.
    Brandon, Florida

  • 10.  RE: 12 heavy notes

    Posted 07-06-2018 08:18

    As Terry has pointed out, more information is needed, like up-weight numbers to go with some of those down-weight numbers. When, in an earlier post you said that the DW on some notes was around 70 grams and the UW was"normal", if by normal you mean 20 grams or so, then you have a serious friction problem on those notes! If, on the other hand, by "normal" you mean UW numbers that indicate friction is NOT out of the usual range (e. g, DW 70, UW 45, for 12.5 gr. of friction), then it starts to look like some key leads might be missing from those keys.


    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA

  • 11.  RE: 12 heavy notes

    Posted 07-06-2018 09:09
    Edited by Karl Roeder 07-06-2018 09:19
    Mr. Weiss,

    Have you looked carefully at the clearance between the hammers? The Baldwin L doesn't have a lot of room for the hammers to travel to the strings without interfering with one another. The problem is worst in exactly the areas you are seeing the problem in. I recently ran into this on a set of Hamburg Steinway hammers that "grew" a bit after 7 or 8 years in the everglades. I had to trim some felt on the sides at the bottom of the hammers.  I've attached some photos to try and be more clear.

    Karl Roeder
    Pompano Beach FL

  • 12.  RE: 12 heavy notes

    Posted 07-06-2018 09:27
    Can you provide the following on some of the offending and non offending notes?  Downweight alone is insufficient to assess.


    David Love RPT
    415 407 8320

  • 13.  RE: 12 heavy notes

    Posted 07-06-2018 09:49
    Second cup of coffee made me think. When I replace key bushings sometimes an errant drop of water or glue can end up in the balance hole of the key. The balance hole then gets re-sized and end up much tighter than before. That can cause a dramatic increase in down weight. You would also note a co-responding decrease in up weight despite the heavier touch number.

    Karl Roeder
    Pompano Beach FL

  • 14.  RE: 12 heavy notes

    Posted 07-06-2018 12:19

    What Karl said is precisely what I was thinking. Also, though the hole might not be "tight", the thickness of the bottom plate, plus a tightened hole (binding at the TOP of the hole rather than the bottom of it) will be "springing" the pin.

    The first time I encountered this it took me quite a while to figure out what was going on. Tapered tool from the top was the solution.

    This may not be it, but look carefully. You should be able to feel a weird increase in required touch in the bottom 3rd of key travel. Or actually see the pin moving. (That was how I found out).

    Hope you find the solution.


    Peter Grey
    Stratham NH

  • 15.  RE: 12 heavy notes

    Posted 07-06-2018 10:04
    This may be obvious but I’ve had occasional friction issues with knuckles rubbing against their neighbors. And also back checks. Like Karl suggested with hammers, I’d eliminate parts interference first. If downweight is 70 some and upweight is “normal” so about 20-25, than that’s way too much friction. Or am I missing something?


    Sent from my phone, forgive typos!

  • 16.  RE: 12 heavy notes

    Posted 07-06-2018 17:37
    Thanks for all of the replies.  I did not have a chance to get to the shop today.  I'll be there tomorrow to check my numbers and run through some of the suggestions.

    I did take a quick look at my sheet of down weights and up weights and friction everywhere is between 8 and 12 grams, so that is not the main culprit.  I also looked at my chart of hammer weights and it corroborated what I had said earlier, the weight of the new hammers matched the old ones very closely.  I was also very careful after replacing the key bushings  to make sure all of the balance rail holes were free. Also I have already checked very carefully for any rubbing parts and did not see any.

    Still, I never trust my self completely, so I will re-examine all of this tomorrow with the suggestions from the list in mind.

    David Weiss
    Charlottesville VA

  • 17.  RE: 12 heavy notes

    Posted 07-06-2018 20:47
    On those 12 notes, if the UW is also above the others, there is a lack of lead in the front of the key. If the friction is the same, lead deficiency.


    Jon Page

  • 18.  RE: 12 heavy notes

    Posted 07-07-2018 17:22

    Comment from Jon Page:  "On those 12 notes, if the UW is also above the others, there is a lack of lead in the front of the key. If the friction is the same, lead deficiency."

    That is the conclusion I finally came to.  My measurements reveal that there is not a friction problem, but the heavier notes do have UW above the others.  Additionally there is very little leading in the keys.  This makes me think I should add lead to the 12 heavy keys. 

    When I started the project I did not take DW and UW measurements of all 88 keys.  I only took measurements of all the C notes.  That was a mistake, I'll call it a lesson learned.  At the completion of the project I measured DW and UW of all the keys and at that point saw the 12 notes that were too heavy.  I now believe that was the situation before I did any work.  However since I did not measure all of the notes I was not aware of that.

    Thanks for all of the input.

    David Weiss

    David Weiss
    Charlottesville VA

  • 19.  RE: 12 heavy notes

    Posted 07-07-2018 16:19
    what type of glue and how much did you use for the keybushing felt ? if for some reason you used pvce glue it can ooze out and it gets very rubber like . the balance pin hole on the key may also be swollen just enough. it also may not be a bad idea to check all of the action centers of a whippen using a gram gauge as well as the damper lift timing of the dozen notes. early lift can give heavy feel

    James Kelly
    Pawleys Island SC

  • 20.  RE: 12 heavy notes

    Posted 07-07-2018 19:47
    I used hot hide glue for the key bushings.  I've looked at them very carefully and they are fine.

    David Weiss
    Charlottesville VA