Help on Gotoh UPTL install? - Accidentally reamed hole too big

SkeeterAB

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I am doing my first Gotoh UPTL install where I have to widen the holes (on a fluke). Apparently I was not sufficiently patient on the first one and went a little past the right diameter so the tuner is a little wiggly when you insert it in the hole. The diameter of the hole measured 9.7 mm on a digital caliper. I did a good job on the other 3, but this one is a bit worrying. When I put on the back and tighten it up it does not seem to move at all. Should I leave it alone as long as it doesn’t wiggle when tightened, or should I put a little strip of paper around it to get rid of the wiggle before I tighten it down and put on the strings?

Thank you in advance for any help.IMG_1473.jpeg
 
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Best way IMO would be to plug it and start from scratch. But that's a big job.

Other option, since you are only 0,2 mm off, would be to flood the hole with thin CA-glue to get the sides hardened, then slowly build up a couple of layers with high viscosity CA or a couple of layers of epoxy, and repeat the reaming. Tape off the headstock to avoid spillage, and be prepared to whip out the razorblade (two ends with cellotape as a depth-stop) to clean up. After that, same procedure with the reamer.

Last option would be to insert some sort of sleeve (a "bushing" with outer 9,7 and a thickness of 0,1), but I would not recommend paper. Unless you can get that stabil, again with flooding with a thin CA. Lining with veneer would be very difficult, so maybe copper, brass or aluminium. In those cases, make the sleeve somewhat shorter than the thickness of the headstock (0,1 below the surfaces of the headstock).

Try the easy ones first, see if it works or not. There's allways possibility to go back and try an alternative...

Good luck! 🍀
 
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Best way IMO would be to plug it and start from scratch. But that's a big job.

Other option, since you are only 0,2 mm off, would be to flood the hole with thin CA-glue to get the sides hardened, then slowly build up a couple of layers with high viscosity CA or a couple of layers of epoxy, and repeat the reaming. Tape off the headstock to avoid spillage, and be prepared to whip out the razorblade (two ends with cellotape as a depth-stop) to clean up. After that, same procedure with the reamer.

Last option would be to insert some sort of sleeve (a "bushing" with outer 9,7 and a thickness of 0,1), but I would not recommend paper. Unless you can get that stabil, again with flooding with a thin CA. Lining with veneer would be very difficult, so maybe copper, brass or aluminium. In those cases, make the sleeve somewhat sporter than the thickness of the headstock (0,1 below the surfaces of the headstock).

Try the easy ones first, see if it works or not. There's allways possibility to go back and try an alternative...

Good luck! 🍀
Thank you! Also, what is CA glue?
 
The pin on the base of the tuner is supposed to anchor in the wood when tightened to prevent turning. The extra tenths of a millimeter in hole size shouldn't be an issue.
 
IIWM, I would just push it towards the nut (the way the string tension would pull), tighten it up and call it a day. You're not far off and it doesn't wiggle (and won't rotate) when snugged up. CA could leave a big mess.

Good for you for installing your UPT tuners, on a MF no less! Many have wished for an alternative to those friction tuners, in fact there is a long thread on the topic...not sure anyone had tried UPTs.
 
The pin on the base of the tuner is supposed to anchor in the wood when tightened to prevent turning. The extra tenths of a millimeter in hole size shouldn't be an issue.
Correct, i forgot about the tack pin...
But flooding the endgrain with CA wouldn't harm to prevent the possibility of the tuner rocking (e.g. when taking off tension during string change).
It's a Belt & Suspenders redundancy I guess.
 
↑↑ Agree. Before breaking out the glue and the additional trouble that would entail, I'd try it as-is. At most you could wrap the post with a few turns of plumber's Teflon tape to make it snug.
I should have thought of Teflon tape. I didn’t check my messages until I got back from the hardware store.
 
Thank you all!

I only saw the rest of the messages after I got back from the hardware store. Because I just bought wood filler to match my wood I decided to put a thin layer of the wood filler on the inner surface of the hole with a toothpick. I will let it dry tonight and re-ream tomorrow. Wish me luck:)


IMG_1478.jpeg
image.jpg
 
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Thank you all!

I only saw the rest of the messages after I got back from the hardware store. Because I just bought wood filler to match my wood I decided to put a thin layer of the wood filler on the inner surface of the hole with a toothpick. I will let it dry tonight and re-ream tomorrow. Wish me luck:)


View attachment 170259
View attachment 170260
The wood filler looks a little heavier in spots. Wondering if this would result in a re-ream that is off center. Take care to ensure the hole remains center and go slow 😎
 
The wood filler looks a little heavier in spots. Wondering if this would result in a re-ream that is off center. Take care to ensure the hole remains center and go slow 😎
Thank you. I will keep that in mind and watch it carefully as I go. It is easier to align with the fluke than with a normal ukulele head because the gradually tapered reamer also extends through the hole on the opposite side of the head. I also pressed the wood fill in a bit with my finger so that I can clearly see the outline of the original hole.

*Edit: Because my usual insomnia set in I went back and cleared out the center of the hole with the small end of the reamer before the wood filler completely set. See pic.

IMG_1481.jpeg
 
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Nice work, way to install and work through the fix 👍. You might link to this thread for future reference:
 
Nice work, way to install and work through the fix 👍. You might link to this thread for future reference:
Thanks for the link. I will save it.
 
Nice work. I plan on changing a set rear facing frictions, tuners with Gotohs, this week. Same button color.
 
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