Gotoh Planetary Tuner Installation – Kamaka Tenor

dkame

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I decided to change out the stock friction tuners on my Kamaka tenor built in the early 1990’s. After hearing good things about the Gotoh planetary geared tuners (4:1 ratio), I wanted to install these. The one concern I had was that I would have to drill out the holes in the headstock for the larger diameter Gotohs. I would need to go from a nominal 21/64” diameter to 3/8” diameter. I wasn’t thrilled with the idea of doing irreversible modifications (damage?) to a very expensive instrument. But after a couple of weeks of fighting the tuning on new strings and reading the forums, I convinced myself that there was more upside here.

Info on the Gotoh tuners can be found at:

Forum Thread: Uke Talk, Gotoh Planetary Tuners

http://www.g-gotoh.com/international/?btp_product_category=ukulele-pegs
or
http://www.japarts.ca/Gotoh/Gotoh-Products-UPT.asp

From the Gotoh website, UPT is for 10mm-12mm (0.39”–0.47”) and UPTL is for 11.5mm-13.5mm (0.45”-0.53”). The headstock on my tenor Kamaka is 0.51” so the UPTL was the correct version for this install. I got my tuners through Hawaii Music Supply (aka HMS, aka The Ukulele Site) using the UU special discount, but you could also get parts from japarts where there are more styles available.

I chose the gold with black ovals UPTL-UBB-G. It is important to note that overall “size” of this Gotoh tuner/button is smaller than the stock friction tuners on the tenor Kamaka, more like the size of the tuners on my soprano Kamaka. If you want to keep closer to the same scale of appearance on a tenor, the UB4 “tulip” shaped button looks a bit bigger. The photo shows the comparison between the original on the top and the Gotoh on the bottom:

gotohtuners1.jpg

I’ll document the whole installation process in subsequent entries. Just so you know, in the end it turned out great and the new tuners are fantastic. I did learn a few things and there are probably more professional approaches – but it can be done by an amateur like me. Let me know if you have questions and I’ll try to answer them.

Also, I'm new to posting - can anyone tell me how to insert the photos directly into the post? Or do they just need to be attachments?
 
Gotoh Planetary Tuner Installation – Kamaka Tenor
Part 1 – Tools List

MINIMUM
Flathead Screwdriver
Throwaway Pen – ex. Bic Round Stick
Drill
1/8”-1/2” Step Bit (Unibit)
3/8” All Purpose Drill Bit
10mm 6-sided Socket, or 10mm wrench or Adjustable wrench
Patience

OPTIONAL BUT RECOMMENDED
Blue Painter’s Tape
1/8”-3/8” Drill Guide (to drill straight)
2” C-Clamp
Scrap Wood, thin, flat

NOT NEEDED BUT COOL TO HAVE
Calipers – I borrowed a set from my work to measure the head stock thickness. But since I had them, why not check the diameter of ukulele strings? Wow – did you know some brands are dead-on the advertised size up and down the string? And some are NOT? And some strings are not round? That will be a post for another day…

SHOULD HAVE HAD (Can’t have everything…)
Drill Press
Arbor Press
 
Gotoh Planetary Tuner Installation – Kamaka Tenor
Part 2 – Removing the Old Tuners

Remove the strings from the tuners. I left the strings attached to the bridge and they didn’t cause any problems. Thinking back now, I could have coiled the strings up and stuffed them in the sound hole and that would have kept them out of the way. Or you could just take them all the way off.

Using the flat head screwdriver, unscrew the thumbscrew and remove the tuners. For future reference, the stepped side of the washer goes towards the spring when you put them back together (after you pick the pieces up off the floor). You will see that there is a collar pressed into hole in the head stock. The correct way to remove this would probably be to use an arbor press or a C-clamp where you insert a dowel on one side and scrap of wood with an oversized hole drilled out on the other and then you just press out the collar.

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So my way of removing it was to find a pen that would fit in the hole (a Bic Round Stic) and use it to push out the collar. First, remove the writing part of the pen, leaving the tube. FYI – if you don’t, the ball point WILL break through the cap and mess up your working surface. I’m not saying anything more about that.

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So you insert the pen tube into the backside of the hole and carefully “thunk” the pen against a hard surface (like the floor), holding the headstock firmly. Happily, the first collar popped out easily, and the second, and the third. The fourth one was naturally in there solid. How much and how hard is too much “thunking” for the uke? This was the most nerve-wracking part of the project. I thought back to the number of times I have crashed my uke into a table or the back of a chair or a music stand. So maybe a few more thunks would be okay. Thankfully, the collar started moving and it came out with a few more taps. So this part was done – no casualties, except my floor.

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Gotoh Planetary Tuner Installation – Kamaka Tenor
Part 3 – Drilling out the Holes

I’ve drilled holes in wood before and I’ve chunked out splinters, made ovals, and propellered a stick across the room. So I was a little wary about free hand drilling. Now a Unibit would have been perfect since they step up the diameter a little at a time and don’t grab as much. But the each section is very short so you can’t get the depth you need. I figured if I could get the 3/8” diameter started with the Unibit, I could finish with a regular 3/8” drill bit without worrying about tearing out a chunk of koa. To be on the safe side, I used a drill guide to keep the hole straight.

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One important thing to note is that you don’t have to go all the way through the head stock with the 3/8” diameter to install the tuners. And you don’t really want to – I’ll explain later. You just need to go about 0.3” deep from the back side.

I marked the 3/8” diameter on the Unibit with a Sharpie so I could stop before hitting the next diameter. After drilling these pilots, I set the shank end of the 3/8” drill bit into the pilot to center the drill guide. Once set, I clamped the drill guide to the head stock using scrap wood and painter’s tape to protect the finish. MAKE SURE YOU ARE DRILLING FROM THE BACK SIDE OF THE HEAD STOCK!

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I marked the drill depth on the bit (thickness of drill guide + drill depth 0.27”) and carefully started drilling. GO SLOW!! THE BIT CAN GRAB AND GO FASTER THAN YOU WANT!! You really want to be prepared to pull back and get off the trigger. This is the reason that you don’t want to drill all the way through – so you don’t blast out the front side and split out a chunk of wood.

gotohtuners8.jpg

So if all went well, you should have a nice 3/8” hole that is centered up with the original tuner hole. CAUTION – IF YOU TRY FIT CHECKING THE GOTOH TUNER, BE AWARE THAT THERE IS A SHARP ANTI-ROTATION PIN ON THE BACK SIDE OF THE GEAR BOX. IF YOU SPIN THE TUNER WITH THIS PIN AGAINST THE HEAD STOCK, YOU WILL END UP WITH A GOUGE. You won’t be able to see this once the tuner is installed but you will hate yourself on principle.

Here are some alternate suggestions that I might have tried after practicing on some scrap wood: 1. Free hand drill the 3/8” hole without the drill guide (but still using the pilot and only if I thought I had a steady hand and could drill straight); 2. Forget the Unibit pilot, center the drill guide by eye and go for it with the 3/8” drill; 3. Use a reamer to open up the hole (I did visit a couple of hardware stores but couldn’t find one and I didn’t want to pay for a StewMac one).
 

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Gotoh Planetary Tuner Installation – Kamaka Tenor
Part 4 – Installing the Gotohs and Restringing the Uke

To restate a warning from the last post: CAUTION – IF YOU TRY FIT CHECKING THE GOTOH TUNER, BE AWARE THAT THERE IS A SHARP ANTI-ROTATION PIN ON THE BACK SIDE OF THE GEAR BOX. IF YOU SPIN THE TUNER WITH THIS PIN AGAINST THE HEAD STOCK, YOU WILL END UP WITH A GOUGE.

You might have a choice, depending on how obsessive you are. The orientation of the stamping (PLANETARY-GEAR GOTOH JAPAN) on the back side of the tuner gear box is random. If you feel the need for this labeling to all face the same direction, the anti-rotation pin will poke into the headstock at a different radial location for each tuner. If you don’t care one way or the other, you will surely live a much longer and happier life.

It is not necessary to pre-locate a hole for the anti-rotation pin. Just firmly push the tuner straight into the head stock without rotating it. Put the washer, flat side down on the front side of the tuner and thread in the retaining collar, tightening snugly with a wrench. And that’s it – you’ve done it.

gotohtuners10.jpg

The Gotoh tuner has a shorter and smaller diameter peg section where the string wraps around the tuner. You will need to remove quite a bit of the excess string slack when you put the strings on, especially with new strings, since you will not be able to take up as much of the slack with wraps around the tuner. You may need to readjust and cut off more excess once the strings start stretching out.

I am completely happy with the new tuners. They are smooth and make tuning a zillion times easier. Overall, this was a very successful project, taking a morning for me to do. If I did this again, I bet it would take well under an hour. Let me know if you have any questions!
 

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Derek,
Thanks for walking us through the process! I have these tuners on my new super concert and they are great. I'm now considering swapping out the friction tuners on my other uke for these Gotohs. Is there a special code for the discount through HMS?
 
Derek,
Thanks for walking us through the process! I have these tuners on my new super concert and they are great. I'm now considering swapping out the friction tuners on my other uke for these Gotohs. Is there a special code for the discount through HMS?

Check out the Forum Thread: Uke Talk, Gotoh Planetary Tuners. At the end of the 4th page, AndrewKuker gives the models, pricing, and info on the code and later in the thread, instructions on how to enter it on the order form. If you can't find it, let me know.
 
You might have a choice, depending on how obsessive you are. The orientation of the stamping (PLANETARY-GEAR GOTOH JAPAN) on the back side of the tuner gear box is random. If you feel the need for this labeling to all face the same direction, the anti-rotation pin will poke into the headstock at a different radial location for each tuner. If you don’t care one way or the other, you will surely live a much longer and happier life.

(Emphasis above is mine.) - Great thread - but this is probably the best advice in the whole thread!

BTW, I've put a set of the tuners on my KoAloha and will be putting some on my other ukes as string changes come up. They are really great tuners. I've never had a problem with friction tuners but these are a little more precise without it requiring an annoying number of turns when changing strings the way most geared tuners do. They also weighed exactly the same as the stock KoAloha friction tuners and the slightly smaller buttons left room for me to semi-permanently mount a Mini NS headstock tuner between the buttons without interference.

One thing is worth mentioning. If you are the sort that is very anal about "shiny" then don't buy the "chrome" tuners. While some of the internal parts are plated, the nut and washer that show from the front and the body on the back are not plated and not shiny. They look like basic zinc-plated hardware. This wasn't a problem for me but if you like shiny, or think shiny might improve the resale value, make sure you get the gold or black ones!

John
 
Thank you for the great write up. You have given me the confidence to try this upgrade now. Those tuners look really good on your Kamaka.
 
Thanks for documenting the installation process. I have a set of these on my super soprano and love them. I thought about getting some for a couple of my other ukes, but I wasn't sure if I had the necessary tools and skills to do the installation myself. This thread is very informative, and I think I can do it.
 
Thank you for the great write up. You have given me the confidence to try this upgrade now. Those tuners look really good on your Kamaka.

Thanks for documenting the installation process. I have a set of these on my super soprano and love them. I thought about getting some for a couple of my other ukes, but I wasn't sure if I had the necessary tools and skills to do the installation myself. This thread is very informative, and I think I can do it.

Thanks for the kind words and feedback. I'm sure you will be happy with the results. Also, I've discovered that you can use a small Phillips head screwdriver to adjust the resistance of the tuners, in case you either want them to turn more freely or to hold tighter against high string tension. Although I would say that the factory settings are perfect.
 
Thanks Derek for the instructional post on changing out Schallers to Gotoh UPT's. The step-by-step advice came in very useful while changing them out on my Kamaka HF-1. The Bic pen trick was especially a good one. I did not use the drill method, but went with using a violin reamer from both sides (see HMS Gotoh video). My ADVICE to anyone doing this method: Do not use a cheaply-made reamer. Use a German or American made tool of higher quality. The cheaper versions from EBAY or Amazon won't cut, but with just chew or crush the wood. Also, even though my headstock was slightly over 12mm, I went with the UPTs, not the UPTLs. They will just fit, but the posts will be nice and short on the face side. Better breaking angle for the nut to post. Be methodical, slow and careful and will it will take no effort or time. The UPTs make a world of difference! Lighter and very accurate no-fuss tuning. Hightly recommended!

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Couple of things that may be of assistance to others doing this, one which apples to reso's.
1. The tightness of the tuner can be adjusted by tightening/loosening the screw on the button.
2. if doing this to a reso, do one string at a time. This will keep the biscuit/saddle in place so you do not have to fiddle with to get the intonation correct.
h
 
Yet one more reason I am so thankful for the UU Forum day after day. I found this thread to be highly informative as I undertake the same process - and quite humorous in the appropriate places. So, to 2013 @dkame, thank you!
 
Good stuff. When I visit Kamaka factory next time I will ask if they have Gotoh replacement tuners in stock and if they do then this thread might come in handy. Thanks.
 
I got my set from TUS - like $90 and well worth it (in my opinion) for any ukulele joining the permanent stable!
 
Good stuff. When I visit Kamaka factory next time I will ask if they have Gotoh replacement tuners in stock and if they do then this thread might come in handy. Thanks.
They should have them as it is used on the Ohta san models
 
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