Ron brought in an ancient mahogany Favilla Baritone that he found on the internet. The original tuners were slipping making it impossible to keep in tune. I had just bought some of the new Gotah UPT tuners.
It was easy to remove the old friction tuners.
. Here are the Gotah's. The one on the right is dis-assembled. The top piece threads down onto the bottom piece clamping it to the peg head. They have internal gears giving them a 4 to 1 gear ratio.
I had to drill much larger holes through the old peg head. This larger hole makes the Gotah an easy replacement. Old ukes Friction tuners usually had pretty small holes.
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The tuners have a tiny sharp point protruding from the gear box to prevent the tuner from turning. You mark the place where the point is to be and punch a hole for it with a thin awl. see that tiny point on the right hand photo?
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Once the hole is drilled they are very easy to install. They turn very smoothly and hold their position firmly. No slippage noted. I think they will be excellent to upgrade old ukes.
You adjust their tension with a very small phillips head bolt on the back of the thumb knob.