CAUT

  • 1.  Boston grand rim separating

    Registered Piano Technician
    Posted 09-03-2025 13:40

    I'm working on a 22 year old Boston GP-193 grand. I am told it was in an older (now demolished) building with steam heat for about a decade before I started. The inner and outer rims are separating, up to 1/16" gap in places. The veneer has lifted from the front corner where it's flat on the treble side to where the bent side begins (included just for information). I am going to recap the bridges and restring, so the piano can be flipped over without the plate. Attempting to clamp the rim completely closed will probably not do much good. The plan is to fill the voids with epoxy and just as much clamping pressure as it will accept. I typically will use System Three Clear Coat for this as it has a high tensile, flexural modulus and low elongation properties when cured, and because it is low viscosity to flow into the voids. Looking for feedback from anyone who has already done something similar. TIA 



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    Dave Conte, RPT

    Piano Technician in Residence
    The University of Tennessee
    College of Music
    Knoxville TN
    (817) 307-5656
    Owner: Rocky Top Piano
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  • 2.  RE: Boston grand rim separating

    Registered Piano Technician
    Posted 09-03-2025 15:25
    My take is that for grands with separate inner and outer rims, the outer rims is essentially just "furniture," for looks, while the inner rim is designed to hold the soundboard, plate and strings. 

    From watching how grands were made in the Sauter factory, I saw that in production the inner rim is strung, chip tuned, then the action is fit to it and most of the work is done. 

    Only after this is an outer rim glued to it. This is, of course, in contrast to the Steinway method where the outer and inner rims are glued together all at the same time. 

    So I would look at filling the gap between the two as being more cosmetic than structural.

    Regards,
    Fred Sturm
    http://fredsturm.net
    www.artoftuning.com
    "One's real life is so often the life that one does not lead" (Oscar Wilde)






  • 3.  RE: Boston grand rim separating

    Registered Piano Technician
    Posted 09-03-2025 15:36
    Thank you Fred. I agree in part, but there is a lingering instability problem with this piano, and although I don't have any empirical evidence,
    I believe that not having that extra structural integrity is contributing to it. 




    Original Message


  • 4.  RE: Boston grand rim separating

    Posted 09-03-2025 15:41
    That is a known manufacturing defect for Boston grands from that era. When I was working at the Steinway dealer back then,it was happening to new pianos on the showroom floor.

    Richard T. Cromwell




    Original Message


  • 5.  RE: Boston grand rim separating

    Registered Piano Technician
    Posted 09-03-2025 16:11

    Shoddy work. I am currently rebuilding a Marshall & Wendell grand where gaps between inner and outer rims are as large as one inch. 8 wood screws

    hold the two together, other than joinery at the front. I plan to fill these gaps with maple veneer of varying thicknesses, glue and stainless steel wood

    screws after glue has dried. Then I can fit the new soundboard tight to the outer rim with the added stability.



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    Parker Leigh RPT
    Winchester VA
    (540) 722-3865
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    Original Message