How to widen metric sized knobs?

Discussion in 'Tele-Technical' started by hydra19, May 19, 2020.

  1. hydra19

    hydra19 TDPRI Member

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    I got a MIJ Tele with some real nice relic knobs, I really like them but could not find a similar replacement to fit 6.35mm (imperial) solid shafts. I prefer these to some that are going for $50 on ebay so surely there must be a DIY way?

    I managed to enlarge the control plate with just a metal round file but the knobs are proving much trickier. I used the file and even resorted to a hand drill, holding knob with a capo but it doesn't seem to be getting much larger. I can see bits of brass coming off from the inside but it still doesn't fit the shaft.

    Should I use a drill but that fits in the hole and use that to widen the sides of the hole or should I go for a bigger drill bit and try to drill that in to fit? Any other tips?
     
  2. SPUDCASTER

    SPUDCASTER Poster Extraordinaire Silver Supporter

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    Machine shop close? Take the guitar with you so they could measure the pot shaft.

    I'm sure they will have a drill press. Couldn't be very expensive.

    Sorry, forgot you're possibly quarantined. It's business as usual here.

    Do you have the right size drill bit? A vise or a pair of vise grips?

    The capo seems pretty unstable.

    I guess just take it slow and be careful.
     
    Last edited: May 19, 2020
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  3. Matthias

    Matthias Friend of Leo's Gold Supporter

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    Have you got a pic of the knobs? It could be easier to get a new set and relic to your own to taste.

    Otherwise, what size drill bit are you using?
     
  4. Ricky D.

    Ricky D. Doctor of Teleocity

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    You should use a drill that s the size you want the hole to be, slightly larger than the shaft.

    Do not try to hold the knob in your hands. Dangerous. Use a vise.
     
  5. alnico357

    alnico357 Tele-Afflicted

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    I have done this with a drill bit. It worked fine. 8mm vs 3/8" is not very much.
     
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  6. hydra19

    hydra19 TDPRI Member

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    should I use a 8mm drill bit, even a 7mm doesn't fit and seems tough. Probably because I don't have a vice so can't give it a lot of pressure or force, I'm just letting it do its own work, but not making much progress
     
  7. LutherBurger

    LutherBurger Friend of Leo's

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    He's talking about the knobs, not the control plate.

    6mm vs 1/4"

    Which isn't much, either, but without the proper tools, skill, and safety precautions this could turn out less than well.
     
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  8. hydra19

    hydra19 TDPRI Member

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    6.5mm bit just goes in and doesn't seem to be doing much, while the 7mm bit can't go in and is actually widening the top of the hole. I got proper tools, some skill and a little safety precautions but it might be more trouble than it's worth. Thank you for the advice
     
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  9. alnico357

    alnico357 Tele-Afflicted

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    I have reamed out brass knobs with a drill bit to fit larger diameter shafts. I clamped the knob in a vise and drilled out the very little material needed. It worked like a charm.
     
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  10. LutherBurger

    LutherBurger Friend of Leo's

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    6.5mm should be wide enough to fit on a 6.35mm shaft, right?

    I'm not a machinist and I can't argue with success, but I don't consider a hand drill and a capo to be proper tools for the job.
     
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  11. Gardo

    Gardo Tele-Holic

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    I've done this same thing ,but then I have a drill press and a vise.
     
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  12. moosie

    moosie Doctor of Teleocity Ad Free Member

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    :lol::lol::lol:


    Me neither...
     
  13. Frodebro

    Frodebro Doctor of Teleocity Ad Free Member

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    Should probably have the first aid kit nearby and ready to go, because the hand drill & capo method tends to cause tissue damage and mild to excessive bleeding.
     
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  14. moosie

    moosie Doctor of Teleocity Ad Free Member

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    Works best on a red guitar.
     
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  15. hydra19

    hydra19 TDPRI Member

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    Thanks for the mature comments, keep the jokes comin', they are really helpful in this case
     
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  16. Frodebro

    Frodebro Doctor of Teleocity Ad Free Member

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    It was posted humorously, but trying to use a capo for a clamp to enlarge a hole in a hunk of metal with a hand drill is asking for injury.
     
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  17. Si G X

    Si G X Tele-Afflicted

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    wouldn't it be easier to change the pots?
     
  18. hydra19

    hydra19 TDPRI Member

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    Sorry guys, of course I would not risk injuring my playing hand over a couple of knobs. I have given it up for now as I don't have the tools to do it safely. I take my comment back, I do enjoy the humour on here, just wish there was a way for me to do it, I came here for advice, I got it and won't go to those lengths.
    I had injured my hand twice trying to tighten Mosrite bridge nuts, and learned my lesson right there. Thanks for warning me of the danger, I mean that
     
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  19. hydra19

    hydra19 TDPRI Member

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    I did get new pots, with a prewired harness so want to make use of that. Knobs are £10 and the least important in terms of looks, since they're all chrome and pretty similar
     
  20. Telecentric

    Telecentric Tele-Holic

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    * removes capo from 'pliers, clamps and cutters' tool box drawer, and slowly backs out of thread *
     
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