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Thread: Help with an IBM Model F repair

  1. #1
    Join Date
    Feb 2019
    columbia MD U.S.A

    Default Help with an IBM Model F repair

    Iíve been trying to restore a model F keyboard. However, even after reassembling the keyboard multiple times it keeps sending out garbage or not working at all. It just continues to send out a 301 error After doing some research on this issue I found an article that points to a screw/bolt on the top of the contact pad not being tight enough.

    However when I went to tighten the screw/bolt down it wouldnít tighten at all. After examining it I noticed that the threads might have been stripped. And Iím not sure how well the hole faired either.

    Even if it seems like it grips a little I still get a 301 error on my 5150.

    Is there a simple fix to this or some way to repair/ replace it? Iíve been working hard to restore this model F and it would be a shame just to stop now do to a simple bolt.

    Any help would be appreciated

  2. #2


    (I am assuming that it's one of those really coarse threaded self-tapping screws that threads straight down into a plastic standoff molded into the enclosure.)

    Try wrapping a little paper (or teflon plumbing tape is easier, if you have some) around the screw threads and then carefully tighten it down (but don't overtorque).

    If that won't hold, it might be easiest to ream the hole big enough to superglue a brass standoff inside of, and then use a different screw with the right threads to go into the standoff. I would be leery about reaming the pc board and tapping in a larger screw. But if there is already a metal insert that the screw needs to thread into, this may be the only choice if you can't drill the whole insert out and glue in a new one. The plastic part will probably just snap off when the drill bit catches at the end of the insert, if you try to drill out a metal insert, though. :/

    Also make sure that you (or the previous owner) didn't forget to put the clear plastic sheet on the back of the big pc board (the one with the switch contacts) when the keyboard was reassembled.
    Last edited by bladamson; May 23rd, 2020 at 05:42 AM.
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