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J&C Fischer Grand Action

  • 1.  J&C Fischer Grand Action

    Member
    Posted 02-28-2012 15:25

    I would like some help with a grand piano that is currently so far out that it is not functioning. This is my first foray into such a total disaster and I would appreciate some feedback.

     

    When the instrument was first inspected, all of the hammers were blocking. A past technician had told the owners that they had expanding action brackets, and the symptoms were very similar. This is not the case as the piano is a 1925 J&C Fischer Grand. The let off was adjusted to get the piano to play so that it could be tuned. I am now in the process of determining what the real problem is and how to fix it.

     

    Attached is a spreadsheet with the measurements that I have taken from the piano. (I duplicated it below because I can't tell if it really attached.) The first thing that seems to be a problem is that the hammers may be to long for this piano. They look original, but may not be. They show strings grooves that start quite far down the shoulder to the front or key side of the hammer and stop either at the strike point or just past it. This is what would be expected from a hammer that is hitting the string before the shank has reached 90 degrees. (The hammers are hung at 90 degrees to the shank.)

     

    Another red flag is that the capstans are screwed down into the keys almost to the point of burying the adjustment holes. (A side note is that the brass plating has worn through and they need to be replaced, so if they need to be moved at the same time that is a possibility.) They currently hit the whippen felt toward the back (away from the keys) and not the center.

     

    When checking the relationship of the capstans to the whippen, it was measured that the capstan is 5-6 mm below the line formed from the pivot point of the key and the center pin of the whippen with the key at 5 mm of dip.

     

    Other measurements are included on the chart. I have tried to include all that I have found so far and have access to the piano for more. I have also formed some ideas of what may need to be done, but because of the multiple issues, I would like to get some outside ideas before getting to far along. (The situation with the piano is that there is plenty of time to get it to work properly, but not much money for a lot of parts, if that makes a difference in approach.)

     

    Thank you for your help.


    J&C Fischer Grand 150197 1925

    All measurements in MM











    String Height 187.325 188.913 182.563 185.738 185.738 184.15
    Hammer Flange Height 142.875 142.875 142.875 142.875 142.875 142.875
    Let Off 3.175 3.175 3.175 3.175 3.175 3.175
    Bore Distance 41.275 42.863 36.513 39.688 39.688 38.1







    Actual Bore Distance 53.975 52.387 46.037 46.037 47.625 47.625
    Difference -12.7 -9.524 -9.524 -6.349 -7.937 -9.525







    Action Spread Bass Treble




    116 118










    Knuckle Flange pin to center of wood Diameter of knuckle

    17

    10








    Magic line Capstain distance below line from key pivot point to wippen center pin at 5mm of key dip

    5-6 MM





    -------------------------------------------
    Rex Roseman
    Akron OH
    330-289-2948
    -------------------------------------------


  • 2.  RE:J&C Fischer Grand Action

    Registered Piano Technician
    Posted 02-28-2012 16:28
    Rex,
     I'm on the fly so I just glanced at your post and didn't study your measurements ---  but a few observations-suggestions.
    First --  just because it ain't a newer Young Chang doesn't mean the brackets couldn't fail.
    Some time ago I had a small German grand of no special distinction , built in the 1940's with crumbling distorted brackets.  Getting the replacement brackets and making them work was a saga in itself !
      That being said I would move the whippen rail (If possible) to center the cushions over the capstans.
    Sometimes there are no spacers to block the rail in position and when the screws get loose the rail will move.
    I's a quick and unscientific suggestion , but a recent asian grand (I think pearl river ) was essentially unplayable when this happened and everything more or less fell into place when I visually repositioned the rail as described.
     Just a quick take,
     Tom Driscoll

    -------------------------------------------
    Thomas Driscoll
    Marlboro MA
    508-485-0369
    -------------------------------------------








  • 3.  RE:J&C Fischer Grand Action

    Registered Piano Technician
    Posted 02-28-2012 17:23
    Many of those pianos had pot metal bracket which failed.  I owned a J & C Fischer from the '30s that had the problem.  Somebody used to sell replacements--there were two sizes.  Maybe someone put the wrong size in the piano.

    -------------------------------------------
    Barbara Richmond, RPT
    near Peoria, Illinois


    -------------------------------------------








  • 4.  RE:J&C Fischer Grand Action

    Posted 02-28-2012 17:17
    Rex,

    There are times when one has to do what needs to be done to make an older piano just to function.
    Throw out the specs. All the persons that were around when this piano are long and gone.

    Because of your first "foray", you will have to improvise. Make one key/note work with acceptability, and then you will know what to do with the rest. As to profitability, well, that's another ballpark. Meaning, do you want to learn want must be done on older pianos, or do you only want to make a profit, or is there a compromise somewhere in between. I'm betting flat knuckles, poor drop and let-off at the very least.

    Been there too many times myself. Best of luck.

    Keith McGavern, RPT
    Shawnee, Oklahoma, USA
    tune-repair@allegiance.tv



  • 5.  RE:J&C Fischer Grand Action

    Registered Piano Technician
    Posted 02-28-2012 17:43

    Rex

    What you're not giving is the hammer blow distance. The hammers might be original, but with the capstans buried, I wonder if the back rail felt might have been replaced. When that's too thick, it relates to all the other problems.
    -------------------------------------------
    Willem "Wim" Blees, RPT
    Mililani, HI 96789
    -------------------------------------------








  • 6.  RE:J&C Fischer Grand Action

    Posted 02-28-2012 18:49
    Good point, Wim.

    Hammer distance from the strings would be definitely in relationship to flat knuckles. Back rail felt ... interesting perspective.

    Mahalo,

    Keith McGavern, RPT
    Shawnee, Oklahoma, USA
    tune-repair@allegiance.tv



  • 7.  RE:J&C Fischer Grand Action

    Member
    Posted 04-11-2012 11:57
    This is an update for those of you who remember the discussion about this piano. It was made workable by decreasing the blow distance and increasing the key dip past "acceptable" standards. (1 5/8" and 15 mm) The black key dip was set just so they didn't bury between the whites.

    What I am looking for now are new action bracket options. The only replacements that I have found were from Schaff (1076 Aeolian Action Brackets). Does anyone know of another possible source? The Schaff ones may work, but will take some grinding of the mounting surfaces to match the various rails.

    I have also started looking into action geometry programs and replacement parts.

    Thank you again for all your advice. This project is still moving ahead due to your help.

    -------------------------------------------
    Rex Roseman
    Akron OH
    330-289-2948
    -------------------------------------------



  • 8.  RE:J&C Fischer Grand Action

    Registered Piano Technician
    Posted 04-11-2012 17:26
    Rex,
    Look into WNG's action bracket replacement procedures. Talk to or send an email to Nina, she can probably point you to the proper pdfs etc at their site. There is a 4 day class on this procedure which is offered several times a year. I attended the class in Haverhill MA this past November.
    Patrick Draine

    -------------------------------------------
    Patrick Draine
    Billerica MA
    978-663-9690
    -------------------------------------------



  • 9.  RE:J&C Fischer Grand Action

    Posted 04-12-2012 22:41
    The key dip is 15 mm ( and that would mean that the sharp height is at least 16mm)?
    I'm sorry, that is neither "workable", nor can it be considered "past acceptable standards".

    The term for that is unplayable.

    I would ask other techs in your area to look at the action, maybe even make it the subject of a chapter technical.  Surely something can be done to get the regulation into the ballpark.
    best of luck.

    -------------------------------------------
    Jurgen Goering
    -------------------------------------------








  • 10.  RE:J&C Fischer Grand Action

    Posted 02-29-2012 01:11

    I have a question:

    I don't understand the difference between "Bore Distance" and "Actual Bore Distance" - can you explain?

    Also, I am surely not the only one who is disoriented by your use of thousandths of a mm in your data.  Of course you didn't measure that (one one-thousandths of a a mm = four one-hundred-thousandths of an inch!).  You can safely round up or down to the nearest .5 mm, this is plenty precise for this kind of work, and much less confusing.


    -------------------------------------------
    Jurgen Goering
    Piano Forte Supply
    Nanaimo BC
    250-754-2440
    -------------------------------------------








  • 11.  RE:J&C Fischer Grand Action

    Registered Piano Technician
    Posted 02-29-2012 10:20
    Hi All,

    I am kind of new to this stuff, so I could be missing something. But I think I understand Rex's measurements and will attempt to give my take on them.

    I believe that what he is calling "Bore Distance" is actually the theoretical or ideal bore distance based on the formula: TBD = SH - LD - HCH, where...

    TBD = Theoretical Bore Distance
    SH = String Height
    LD = Letoff Distance
    HCH = Hammer Flange Center Pin Height

    What he is calling "Actual Bore Distance" is the actual bore distance that he has measured on the sample hammers.

    Assuming that these are the original hammers, and that they were bored correctly, something has caused the hammer rail to rise as much as 1.3 cm from its original position. Consequently, no matter how they are regulated, they are going to strike the strings before the shanks are able to rise to a horizontal position. In order to give this action a reasonable blow distance, the capstans have been turned down until they nearly bury into the keys.

    Apparently whatever happened to this action also affected the position of the wippen rail. The extreme spread figures tell me that someone has moved the wippen rail back (away from the pianist) so that the capstans at least make contact with the wippen cushions, albeit at the backs of the cushions.

    It looks to me as though Rex has a real challenge here. Based on my limited knowledge, I have my doubts that this action can be made to work. Something is very, very wrong here. I can't help wondering if Barbara's suggestion is correct, that someone switched out the action brackets with the wrong ones.

    Roger

    -------------------------------------------
    Roger Domeny, RPT
    Domeny's Piano Service
    Colton, CA
    www.domenyspianoservice.com
    roger@domenyspianoservice.com
    (909) 824-2561
    -------------------------------------------








  • 12.  RE:J&C Fischer Grand Action

    Posted 02-29-2012 16:40
    Alright, looking at it that way the numbers do add up.  However, let-off is adjusted by the button  and has no bearing on bore distance.  It is entirely independent of where you drill the hammer, it does not flow into the determination of bore distance  and vice versa.

    Raising the hammer rail will not change the bore as you suggest.

    The hammers are bored too long, and no regulation will change that.  I doubt that the hammers are original. 

    ..and I am still curious about how to measure  to the nearest .001 mm...   :)

    -------------------------------------------
    Jurgen Goering
    Piano Forte Supply
    Nanaimo BC
    250-754-2440
    -------------------------------------------








  • 13.  RE: J&C Fischer Grand Action

    Registered Piano Technician
    Posted 03-01-2012 11:42
    Rex, I thought someone would have replied by now, so hope this is still relevant to you. Per your measurements, the actual hammer bore length is too long. See below for dims taken at the first tenor hammer: MM Inches 182.563 Keybed to string height. 7.19 142.875 Keybed to ham center. 5.63 39.688 Calculated ham bore 1.56 46.037 Actual ham bore 6.349 Excess bore length 0.25 Your string height dimension is low compared to a Steinway (typically 190mm or 7.5" for all but the D), yet the dimension taken to the hammer center is close if not right on to a typical standard Steinway (at aprox.143mm or 5.625")". Were the hammers bored properly to 39.688 mm or 1.56" they would have "squared to the strings" and the string marks would have been centered to the hammer crown rather than under-centered favoring the front face of the crown. Is it possible that the hammers were replaced with an off-the-shelf bore length? Your let-off calculations have nothing to do with the above routine, tho' you must have had some reason to include them. In addition, the correct bore should allow you to raise the capstans in setting a workable blow distance. And this then would adjust the magic line closer to where it should be theoretically (though doubtful ideal). As to the capstan-whip heel interface, this relates to touch and some regulation parameters, and is a setup-alignment-geometry issue that will need to be analyzed separately after the hammer issue has been corrected. The whippen rail may be able to be moved rearward to "optimize" touch. Moving capstans is a last resort. The spread numbers look long, typical numbers looking more like 112 to 113mm, but may be right for that action. Moving the whip rail to the rear of the action a bit will tend to center the capstan to whip heel, will lengthen the spread a tad while lowering the magic line proportionally, and reduce downweight. In addition the hammer (assuming we begin with proper blow) will then rise some (as it "walks" up the rep lever incline) requiring the capstans to be turned down a bit to compensate. The whip move also impacts jack-to-knuckle interface, as well as let-off buttons and a host of regulation details. But it is doable and recommended in many situations. But one step at a time. Fix the hammers first. Hope this helps. NG On Tue, Feb 28, 2012 at 1:25 PM, Rex Roseman wrote: > > > > > I would like some help with a grand piano that is currently so far out > that it is not functioning. This is my first foray into such a total > disaster and I would appreciate some feedback. > > > > When the instrument was first inspected, all of the hammers were blocking. > A past technician had told the owners that they had expanding action > brackets, and the symptoms were very similar. This is not the case as the > piano is a 1925 J&C Fischer Grand. The let off was adjusted to get the > piano to play so that it could be tuned. I am now in the process of > determining what the real problem is and how to fix it. > > > > Attached is a spreadsheet with the measurements that I have taken from the > piano. (I duplicated it below because I can't tell if it really attached.) > The first thing that seems to be a problem is that the hammers may be to > long for this piano. They look original, but may not be. They show strings > grooves that start quite far down the shoulder to the front or key side of > the hammer and stop either at the strike point or just past it. This is > what would be expected from a hammer that is hitting the string before the > shank has reached 90 degrees. (The hammers are hung at 90 degrees to the > shank.) > > > > Another red flag is that the capstans are screwed down into the keys > almost to the point of burying the adjustment holes. (A side note is that > the brass plating has worn through and they need to be replaced, so if they > need to be moved at the same time that is a possibility.) They currently > hit the whippen felt toward the back (away from the keys) and not the > center. > > > > When checking the relationship of the capstans to the whippen, it was > measured that the capstan is 5-6 mm below the line formed from the pivot > point of the key and the center pin of the whippen with the key at 5 mm of > dip. > > > > Other measurements are included on the chart. I have tried to include all > that I have found so far and have access to the piano for more. I have also > formed some ideas of what may need to be done, but because of the multiple > issues, I would like to get some outside ideas before getting to far along. > (The situation with the piano is that there is plenty of time to get it to > work properly, but not much money for a lot of parts, if that makes a > difference in approach.) > > > > Thank you for your help. > > J&C Fischer Grand 150197 1925 > > All measurements in MM > > > > > > > > > > String Height; 187.325; 188.913 > 182.563 185.738 185.738 184.15 > > Hammer Flange Height 142.875 142.875 > 142.875 142.875 142.875 142.875 > > Let Off 3.175 3.175 > 3.175 3.175 3.175 > 3.175 > Bore Distance 41.275 42.863 > 36.513 39.688 39.688 38.1 > > > > > > Actual Bore Distance 53.975 52.387 > 46.037 46.037 47.625 47.625 > > Difference -12.7 -9.524 > -9.524 -6.349 -7.937 > -9.525 > > > > > > > Action Spread Bass > Treble > > > > > 116 118 > > > > > > > > > Knuckle Flange pin to center of wood Diameter of > knuckle > > > 17 10 > > > > > > > > > Magic line Capstain > distance below line from key pivot point to wippen center pin at 5mm of key > dip > 5-6 MM > > > > > > ------------------------------------------- > Rex Roseman > Akron OH > 330-289-2948 > ------------------------------------------- > >


  • 14.  RE:J&C Fischer Grand Action

    Registered Piano Technician
    Posted 03-01-2012 11:47
    Oh whoops! I see others have replied. I made the mistake of picking up Rex's original thread at the old list. Sorry.

    -------------------------------------------
    Nick Gravagne, RPT
    Mechanical Engineering
    Nick Gravagne Products
    Strawberry, AZ 85544
    gravagnegang@att.net
    928-476-4143


    -------------------------------------------








  • 15.  RE:J&C Fischer Grand Action

    Member
    Posted 03-04-2012 14:18

    Thank you to all that replied. Your thoughts have been printed out and compared to the piano and this is what I have come up with so far. Taking the posts somewhat in order I will respond to questions and suggestions.

     

    Tom and Barbara: It is quite possible that someone did exchange the action brackets in the past and put on the wrong size. The ones on there now seem to be solid. I have worked with expanding brackets and they showed cracks and fell apart in places when handled. On reexamining these, there are two cracks where the brackets are tapped to receive action bracket bolts but no other sign of deterioration. They are numbered 108 if that means anything to anyone.

     

    Tom and Roger: My observation of the relationship of the capstan with the whippen cushion was wrong. I got there by observing the capstan from the bass end of the piano with the action on the keys. What I did not realize was there was a chunk out of the cushion on the first bass whippen. When the stack was removed from the keys and turned over, it became obvious that I had made a mistake and that capstans were in the correct position.

     

    Jurgen and Nicholas: You are quite correct that the let off should not have been included in the figures. It's because of the possibility of incorrect thought processes like this that I ran this past the list before making what would have been costly and even more disastrous changes to the action. Thank you for catching this mistake.

     

    Wim and Keith: The starting blow distance may be somewhat of a problem because I had to change key height to get the action to play. At this point there have been test keys that have been setup to check the parameters of key height, dip and clearance to case parts. There is very little that can be done with the key height because the back of the balance rail has no relief and the key hits if the backrail cloth is to low, and the balance rail pins for the white keys are so low that they barely come out of the top of the mortise with the thinnest punching underneath. The blow distance at this moment is hovers around 50mm. The hammers will need to be reshaped so that will give some more blow distance. Even then it is going to be close because the shanks will be just barely clearing the hammer rail. The knuckles are not too flat.

     

    Jurgen: I don't work in metric, but half of the measurements were going to have to be metric on this piano so I looked up a program on the internet that did the calculations, plugged in the inches (converted from fractions to decimals) and copied exactly what it gave me. Sorry for the confusion that caused.

     

    At this point in time, it looks like the action may be able to be made to work with reducing the hammer bore by reshaping, lowering the hammer line with slightly thinner backrail cloth, and possibly using a thinner cloth on the hammer rail if needed. Eventually a new set of hammers will be needed, but not until the summer at the earliest.

     

    Thank you again for everyone that jumped in to help. It's always good to have an extra set of eyes. I have printed your replies and will refer to them as I work this out.



    -------------------------------------------
    Rex Roseman
    Akron OH
    330-289-2948
    -------------------------------------------