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  • 1.  Stripped screw holes in lids

    Registered Piano Technician
    Posted 10-22-2021 08:33


    Two situations in which the holes of screws that fasten things to their respective lids have stripped out. One is a lid indexing pin (is that the correct term for the male part in the lid that drops into the female part that is attached to the inside of the outer rim at the treble end?). That is on a Bosendorfer. The other striped screw holes are for the lock bar screw holes--yes, ALL of them--on a Steinway.

    Have yet to figure out how the lid index screw holes stripped out on the Bosie. There is no sign of any impact on the lid that would have stressed these connectors. As the young people say, "Whatever."

    On the Steinway lock bar, the holes were apparently stripped out by people repeatedly closing the front lid by grabbing the lock bar, rather than the front lid itself. It looks like the screws gradually loosened and eventually stripped out their holes. To add to the challenge, some of the screws are missing, and Steinway no longer provides the 2 1/4" long, #14 flat-head slotted wood screws for the lock bar of this 32 year old model B. Unless I can locate some of those screws from a third party, it would appear that I have no alternative but to go ahead and violate the Steinway-ed-ness of this instrument by using non-OEM screws. (Hey, at least I tried!)

    These are the options I have come up with so far for recreating holes that will anchor the screws in question:

    1) drill out, and plug with wood

    2) use wood putty

    3) use leather and wood glue

    4) use paper towel and thin CA glue

    If the stripped holes were in were a beefier piece of wood, I would plug them. But due to the relative thinness of the lids, that approach could be tricky.

    If you have successfully done this kind of repair, please share how you accomplished it. Idle speculation could also prove useful.

    Also, if you happen to have any of the OEM screws for the 32 year-old Steinway B lock bar (as described above), I would be interested in acquiring them from you. 




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

  • 2.  RE: Stripped screw holes in lids

    Registered Piano Technician
    Posted 10-22-2021 09:53
    When I encountered this problem on a Samick-manufactured piano, I coated the screw threads with CLP, placed an appropriate amount of thick CA glue in the screw hole, sprayed CA kicker on the screws, then inserted them into the holes. The lock bar was not in place when I did this. After a few minutes, I backed out the screws, sprayed a little more kicker into the newly threaded holes, then assembled.  The screws snugged down tightly.  Maybe some kind of fibrous addition like paper towel would have given more structural strength.  I don't know. 

    Floyd Gadd, piano technician
    Faculty of Media, Art and Performance (formerly, Faculty of Fine Arts)
    Department of Music
    University of Regina

  • 3.  RE: Stripped screw holes in lids

    Registered Piano Technician
    Posted 10-22-2021 11:15
    I have tried the plugging method, and found it markedly unsuccessful. It isn't really possible to get a solid glue joint between the plug and the lid. 

    In the worst case, it was the main lid hinge screws on a Steinway B that was freely available to students in the student union building (yes, I know, lost cause). The plugs all pulled out of their holes a month after I finally went to the trouble of doing what I thought might be a relatively permanent fix. (I have no idea what they were doing to the lid to make that happen. I finally refused to provide service on the piano).

    Similar results with plugging for lyre to keybed screws, my own plugs and those of others. When there is enough stress, they just pull out. Perhaps they would work if the plugs were 1" or more in diameter.

    I have come to believe that it is better to do something like what Floyd suggested, or leather and glue, or a similar approach. (For lyre to keybed, a metal insert of one design or other). There are some situations where plugs work, but they are by no means a universally reliable solution to the problem of stripped screws.
    Fred Sturm
    "Travel is fatal to prejudice, bigotry, and narrow-mindedness." Twain

  • 4.  RE: Stripped screw holes in lids

    Registered Piano Technician
    Posted 10-22-2021 11:49
    I have repaired the same lock bar problem on three Steinways.

    If the holes still had some thread, CA with accelerator on the screw as demoed by Bruce Stevens worked just fine for me.

    In one case the lock bar had come all the way off the piano and completely torn out the holes so I used a mixture of epoxy and plane shavings, drilled and tapped new holes in that after it had cured. I thought about using plugs but I think Mr. Sturm is correct, it would be difficult to make that work on a lid.

    I have not had any of these fail after the repair. I will report back if they ever do.

    Wesley Owen
    Evanston IL

  • 5.  RE: Stripped screw holes in lids

    Posted 10-22-2021 20:04
    Once you make the plugs, measure them with a micrometer or caliper. Select an appropriate size drill bit.

    Otherwise you could use threaded inserts and machine screws.


    Jon Page

  • 6.  RE: Stripped screw holes in lids

    Registered Piano Technician
    Posted 10-23-2021 22:44

    I really like Jon's idea of using machine screws & metal inserts. These could be epoxied in place if more strength is needed. 

    Another option would be JB Weld or JB Quick which are dark in color (black & grey respectively). Either filled & drilled or something like McLube 444 applied To the screws...then screws could be removed & tested by hand. Wax paper or perhaps plastic wrap placed on areas until after epoxy has cured. Otherwise it could stick to the lock bar. 

    (screw the All-Steinway method since they don't even offer the THINGS!! No pun intended!) 

    Kevin Fortenberry
    Registered Piano Technician
    Longview, TX 75602

  • 7.  RE: Stripped screw holes in lids

    Registered Piano Technician
    Posted 10-23-2021 22:46
    Wesley, I just saw your post. I like your suggestions also!

    Kevin Fortenberry
    Registered Piano Technician
    Longview, TX 75602

  • 8.  RE: Stripped screw holes in lids

    Registered Piano Technician
    Posted 11-03-2021 07:59
    Hi Alan,   Coming in a little late on this but I have to add an experience I had here on the Island of Martha'st Vineyard.   A Steinway D is used in a very high humidity condition for a summer venue.  No possibility for climate control.   After the first year all the action centers seized up and I repinning all.  The aclimatized action has been working fine for the last 20 years.  The piano is stored in an unheated insulated space to keep it from drying out.   Soundboard is ok  exept for a small section of the sound board by the bottom of the treble bridge that collapsed negatively.  The rib at that spot is hard against the beam.  There is a slight thinning of 2 or 3 notes in that spot but otherwise I'm leaving well enough alone.  The piano is in always in good tune  and tone.    But early on I in its history I went to open the front lid mid winter and there was the lock bar sitting on the front strecher!   Every screw was stripped to the extent that they couldn't even support the weight of the lock bar!

    David Stanwood
    Stanwood Piano Innovations Inc.
    West Tisbury MA