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Bowed pinblock

  • 1.  Bowed pinblock

    Posted 08-21-2022 17:36

    I have a recording studio piano with a bowed pinblock. Most of the time it can get through a multi day session okay, but every once in a while it will go out enough to make me come back the same day. I tune it at least a couple times a week for the past two years for sessions. They have been wanting to replace it for years because of many other issues with the piano, but moving at a glacial pace. It's a Steinway B, 1908. Was wondering if some sort of repair other than replacing the block could be done. 


    The bowed section is worse in the 5th octave. The hammer flange screws would get caught on the block in that section and I had to grind down the screws a bit for clearance. That is where the tuning is most unstable.



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    Tim Michaels
    pianotechtim@gmail.com
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  • 2.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-21-2022 17:44
    The answer is no.

    With what you did to the drop screws, now you not only will you have to replace the pin block, you'll also have to replace the h/s/f. 

    Wim 





  • 3.  RE: Bowed pinblock

    Posted 08-21-2022 17:53
    Drop screws were fine. Didn't need to do anything to them. It was the hammer flange screws as I said above. I didn't say anything about the drop screws.

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    Tim Michaels
    pianotechtim@gmail.com
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    Original Message


  • 4.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-21-2022 17:56
    My bad, didn't read it right. But the answer is still no to the bowed pin block.



    Original Message


  • 5.  RE: Bowed pinblock

    Posted 08-21-2022 18:19
    Before any modifications made make sure 1. Glides bolts adjusted properly. 2. Cleats height is original.
    Some clearance could be gained by lowering the cleats. Of course it will compromise action geometry.
    Looks like good candidate for new block.

    Alexander Brusilovsky


    Original Message


  • 6.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-21-2022 20:38
    If this studio is doing enough work to warrant 100 tunings a year, they should have no trouble getting financing to replace or rebuild the piano.
    I've seen engineers who constantly upgrade their toys tech yet hesitate to invest in their pianos. Frustrating.

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    Steven Rosenthal RPT
    Honolulu HI
    (808) 521-7129
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    Original Message


  • 7.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-22-2022 07:33

    I'll echo what was said about fixing it or replacing the piano. The amount of upgrades these studios go through is mind-boggling.   The trick is getting their full attention that these issues need  to be deal with.  IMO, it's time to arrange a sit-down discussion with those who control the purse strings and let them know the severity of the issue and their options to correct said work. If they choose ignore those suggestions, then this is on them. Plus, it doesn't bode well for them to reserve space for recording artists and the piano can't hold it's own through a normal session.   As someone who does a fair bit of recording session work, plus having been the pianist on several sessions, I can empathize with the artists who must be struggling with the piano.

    Tom Servinsky 

    Registered Piano Technician

    Concert Artist Piano Technician

    Director/Conductor- Academy Orchestra

    Managing Conductor-Treasure Coast Youth Symphony

    Clarinetist-Atlantic Classical Orchestra

    tompiano@tomservinsky.com

    Website: tomservinsky.com

    772 221 1011 office

    772 260 7110 cell

     




    Original Message


  • 8.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-21-2022 21:26

    If the dome shaped flange screws are a problem you can replace them with flat topped screws. I've done this recently. 

    What makes you think the pin block is bowed?  Sometimes replacement #pinblocks are not properly shaped and they can be too thick in the middle pushing them below the stretcher but even then I'm not sure why that would cause tuning instability. I'd look for other reasons. 



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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 9.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-21-2022 21:49
    Very bad fit at the plate flange. Check with a mirror and a business card. Any gap there is going to give the results you describe. 

    How many tuning pins are riding on the plate in their holes? That's a clue.

    I'm betting that the pinblock is NOT glued to the stretcher anymore...yes?

    Peter Grey Piano Doctor

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    Peter Grey
    Stratham NH
    (603) 686-2395
    pianodoctor57@gmail.com
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    Original Message


  • 10.  RE: Bowed pinblock

    Posted 08-21-2022 21:50
    How would a pin block that is binding on the action rail cause tuning instability?
    When the action cavity is too low, I've used a belt sander to raise its height.  Did something spill on the area to cause swelling?
    Is this the original block?
    Measure string height and HCH, the cleats may be too high. The difference between HCH and WCH should be 64 mm.
    B's are notorious for poor geometry.

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    Regards,

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

    Original Message


  • 11.  RE: Bowed pinblock

    Member
    Posted 08-22-2022 00:29
    I would be taking torque wrench readings for every tuning pin in the 4th and 5th octave as well as examining the pin block for cracks, delamination and gaps . Also look at the bridge pins and bridge cap and string seating. If you are tuning this Beast several times week the pins must have low torque . The studio needs to get another piano . I imagine they have to do quite a bit of mixing and re-recording . It would drive me crazy to do multiple tunings on the same piano week after week even if paid well. Was there a roof leak or liquid spill, ac failure at some point ? have the tuning pins been tapped or juiced with tightener ? Have you checked the action brackets for cracks, expansion, movement as well as the action spread.

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    (843) 325-4357
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    Original Message


  • 12.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-22-2022 07:56
    There is another condition that can cause rather frustrating tuning instability. That is excessive and/or uneven downbearing. Excessive DB causes the board to convulse erratically with the slightest humidity change. In addition to what I mentioned earlier, I would check the underside of the soundboard with string looking for inconsistent crown areas and particularly any section under the bridge that has become "oil-canned". If you find this you definitely have a DB problem (in addition to whatever other issues some dingbat may have built into the last rebuild).

    Peter Grey Piano Doctor

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    Peter Grey
    Stratham NH
    (603) 686-2395
    pianodoctor57@gmail.com
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    Original Message


  • 13.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-22-2022 13:09
    Is this really a B?  This is common for traditional stretcher Steinways - 1878 and earlier - but a B?

    Regards,

    Bill

    Bill Shull, RPT, M.Mus.
    www.shullpiano.com
    www.periodpiano.org
    909 796-4226

    Sent from my iPhone



    Original Message


  • 14.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-22-2022 13:41
    Bill,

    I've seen numerous Steinways "rebuilt" with a floating pinblock. If that's the case here (I'm not sure we actually know the degree of work on it) and whoever did it was super careless or just plain ignorant, it could be a compilation of errors now producing fruitage.

    Edit: OTOH if someone has been driving pins in without supporting the block properly, of course the bottom lamination are likely to be bulging. 

    Peter Grey Piano Doctor 

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

    Original Message


  • 15.  RE: Bowed pinblock

    Member
    Posted 08-22-2022 17:09
    One other thing is to get the action out and examine the underside of the pinblock. As Peter pointed out you could see a bulging lamination and may see pins that are deep in their tuning pin holes. If you have various tuning pin heights or little coil to plate clearance its a sign the pins have been tapped probably with no support under the block . If you have low tuning pin torque and put thin ca around a pin and it comes up through other tuning pin holes you have a cracked block. A good mirror and light makes it easy to examine the block but a forward photo by an iphone/ipad will document things. tell us what you find

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    (843) 325-4357
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    Original Message


  • 16.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-22-2022 23:22
    If the pinblock is delaminating in that area it does not necessarily relate to the tuning instabillty.  It's usually only the bottom layer that has cracked loose. The fact that octave 5 has a problem with tuning stability is not unusual.   In any piano, it's inherently the worst octave for tuning stability (aside from the bottom of the tenor bridge) because 1. that's where the melody gets brought out (i.e. it's pounded harder) and 2. the two non-speaking lengths of the string are in sum longer than the speaking length in that area.  The tuning at bottom of the tenor bridge, however, will be affected in a different manner.  Because the bass bridge does not flex to the same extent as the tenor as the ambient humidity changes, the octaves will go out but not the unisons, whereas in octave 5 it's the unisons that go out in a much more random fashion.

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    Cecil Snyder RPT
    Torrance CA
    (310) 542-7108
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    Original Message


  • 17.  RE: Bowed pinblock

    Posted 08-23-2022 08:24
    CBL is worth a try.

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    Regards,

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



  • 18.  RE: Bowed pinblock

    Posted 08-23-2022 08:30
    Work-hardened strings from multiple tunings that do not render well across the bearings. I find this often in the first treble section, especially on Yamahas and such.
    If a string breaks, you'll find that a replacement will render better than the old ones.

    Maybe the capo is not shaped properly, CBL would have minimal affect.

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    Regards,

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

    Original Message


  • 19.  RE: Bowed pinblock

    Registered Piano Technician
    Posted 08-23-2022 21:51
    Considering the fact that the subject piano is a 1908 B (114 yrs old), originally there was clearance between the action stack and the pinblock. There are three possibilities: 1) the height of the action has been raised, or 2) The pinblock is lower than it was originally, or 3) Combination of the above. 

    What follows is: Why is the action taller (if it is) and what can be done about it? Or why is the pinblock lower? It is not stated, but I'm assuming there is some degree of non-original parts in this thing. What are they and what is their condition? 

    Peter Grey Piano Doctor

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

    Original Message