Plastic tuner button removal

Discussion in 'Technical Side of Things' started by Stefan, Jan 26, 2021.

  1. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    Complicated story:*
    I‘d like to remove the plastic buttons from Kluson tuners without destroying them!
    B20C2E8B-78F0-4E54-8F9D-7B0B9F140D8E.jpeg
    Anyone tried?
    My first intention was heat on the shaft and trying to pull them off...

    *it‘s not possible to get those cream colored buttons as spares in germany.
     
    Last edited: Jan 26, 2021
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  2. Ricochet

    Ricochet I Bleed Orange

    Nov 13, 2009
    Monkey Island
    They’re glued on so your only bet is to apply heat and pray... :)
     
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  3. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    I always thought they‘re melted in.
     
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  4. thunder58

    thunder58 Super Moderator Staff Member

    Age:
    62
    Dec 23, 2010
    tappan ny
  5. tartanphantom

    tartanphantom Friend of Fred

    Age:
    57
    Jul 30, 2008
    Murfreesboro, TN
    Depending on the manufacturer and the age of the machines, it could be one or the other, or both.
    I've seen them done both ways.

    Unfortunately, their removal is difficult without resulting in some sort of warping, cracking, distortion or some other type of damage.
     
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  6. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    Thanks Gentlemen.
    I‘ve found some spare buttons I might like, I’m hoping for an ivory color like the Klusons above. The alternative is a set of those Klusons and removing the buttons...
    I like to swap the metal butterbean buttons of a set of new StaTites V97 for ivory plastic knobs for my new Guild.
     
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  7. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    C5DE41A7-1D3F-43F0-95C5-C5D83426B4C7.jpeg
    Fortunately those buttons are perfect!
    So what’s the best way to fix them on the tuners: glueing on or melting on?
     
  8. thunder58

    thunder58 Super Moderator Staff Member

    Age:
    62
    Dec 23, 2010
    tappan ny
    Admin Post
    That's a tuff question . Maybe @mrfixitmi may have a suggestion
     
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  9. mrfixitmi

    mrfixitmi Country Gent

    Mar 20, 2010
    Michigan
    Great question, it depends on the type of material that was used to make the buttons. I use two-part epoxy on cellulose buttons when I work on old banjos. Cellulose does not like to be heated, nor does Acetal, (POM), they can become brittle when they cool.

    Thermoplastics on the other hand can be reheated....Polystyrene, ABS, Nylon polypropylene and polyethylene.

    If you are unsure, I would recommend epoxy.

    Please do not use an open flame, thermoplastics are very flammable.
    If anyone remembers the fake silk Kiana shirts of the 70's and 80's. one cigarette ash, and you became a human torch.
     
  10. Ted Keane

    Ted Keane Electromatic

    46
    Mar 19, 2016
    Ft Collins,Colorado
    I've drilled a hole from the outside in to the stem,and broke the knob off.How are you going to attach the new one?
     
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  11. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    Thanks, I know that video, super helpful. I guess a gap filling superglue or polymer glue is best.
     
  12. tartanphantom

    tartanphantom Friend of Fred

    Age:
    57
    Jul 30, 2008
    Murfreesboro, TN
    I don't particularly like superglue for attaching the buttons, because of its low shear strength. However, it is excellent for solidifying and stabilizing older buttons that are showing signs of cracks, but have not totally disintegrated.

    A two-part epoxy has always been my favorite for installing them, once I've modified the mounting hole to the correct shape for a snug fit.
     
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  13. Back in Black

    Back in Black Synchromatic

    Age:
    71
    534
    Jun 22, 2020
    Ontario Canada
    Stefan,

    This type of plastic button is molded in place, inside the button, the shaft has a ''key'' pressed into it to keep the button secure, and to prevent it from ever spinning.

    These buttons are not removable...at least not without irreparable damage to both the button and the tuner.

    Suggest removing and replacing complete key set.

    Replace with these ''Golden Age'' relic open gear tuners from StewMac, vintage relic'd slotted screws included.

    Proceed with caution!

    Best,

    BIB.

    Golden age relic tuners StewMac.jpg
     
    Last edited: Jan 28, 2021
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  14. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    Thanks,

    as mentioned above I fortunately found spare buttons to replace the Butterbean buttons of the Sta Tites. Phew!
    Now I hope for easy disassembling of those buttons. I‘ll glue the new ones in with 2k-epoxy, like @tartanphantom recommends.
     
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  15. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    @tartanphantom and @mrfixitmi especially:
    Removing the Butterbean knobs was darn easy. New problem: the holes in the new buttons are a tad too large. Can I fill the holes with the epoxy glue???
     
  16. mrfixitmi

    mrfixitmi Country Gent

    Mar 20, 2010
    Michigan
    Stefan, great question.

    That is correct.

    Please help yourself by to removing the air bubbles from the epoxy. You can do this by mixing the epoxy in a container, and drop the container several times so that the air bubbles rise up and out of the compound.

    As far as the holes being too large:
    This is a common problem with banjo tuners from the 1920s and 1940s. The holes tend to enlarge over time, so that the holes are too big for an interference fit. It also helps to sand the tuning shaft where the button is inserted if it is not rough or serrated. This gives you more surface area, and allows the epoxy an area to "grip". I would allow the epoxy to fully cure and harden over 3 to 4 days. Since there is not good airflow around the shaft and knob, drying time takes longer.

    I have been very successful with this approach.
     
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  17. tartanphantom

    tartanphantom Friend of Fred

    Age:
    57
    Jul 30, 2008
    Murfreesboro, TN
    I concur. This is the most straightforward approach.

    An alternative method (some would call it "over-engineering") would be to fit a bit of abs plastic rod into the button, and re-drill the hole to a smaller diameter. Then, proceed with the epoxy. It's a similar approach to filling a worn wood screw hole with scrap and woodglue.

    However, since the buttons are rather small and difficult to work with from the get-go, I wouldn't advise this method unless you had access to a Dremel-style drill press, as it's rather delicate work to re-drill the hole into the abs insert.
     
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  18. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    Thanks a lot!
    That‘s what I‘ve done! I‘ve sanded the shafts, degreased the shafts and the holes of the buttons and put a tiny little piece of plastic in each button. Yup, the holes were also a bit too deep :p
    I applied epoxy in the holes, put them on the shafts (the excess epoxy ran out), moved them to kill the bubbles til they fit good. Cleaned the shafts and the buttons and now: drying. Sitting and hoping for the best ;)
     
  19. Stefan

    Stefan Country Gent

    Jan 20, 2016
    Germany
    Ah, by the way- is it a good idea to apply some heat or is regular room temperature best bet?
    The instructions from the Epoxy glue recommends 24 hrs drying time, but I guess 48 hrs is minimum, right?

    C83F9DC1-8E70-4E8D-ACF8-14CE857AFD04.jpeg
     
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