Are there geared tuners that come out the back of the head stock like froction tuners? I thought I saw some on line somewhere but cannot remember the brand name!
come in two lengths of the main shaft. One is 27.5 mm long, and the other is 19.mm long. The string post is the same length on both of them
Tim Szerlong did an evaluation of them on www.ukeeku.com. A 4:1 ratio is really more appropriate for our instruments than a 16:1 ratio------ unless you enjoy turning the grip.
I recently replaced the friction tuners on my Martin OXK with Gotoh UPTL tuners. The shorter UPT tuners were too short for the thickness of my head stock. Be careful widening the tuner holes. A regular drill bit will tend to grab and tear the holes. A step drill bit or a reamer would be safer.
I wonder what tension you have on the grip/string post in relation to the outside shaft. There is a difference between a 4:1 ratio and a 16:1 ratio. The tension is variable on PEGHEDS, but not on the Gotohs. Some of my ukes still have Gotoh tuners. The weight difference is noticeable between the two different tuning machines. On the banjos, it is not noticeable, but wood bodies are lighter with PEGHEDS over Gotohss
Personally, as a fan of traditional friction tuners, I found Gotoh UPT planetary tuners much better compared with Pegheds (and have used both).
Just my 2c ...
I have a set of the satin Chrome Gotoh UPTs on a Martin 3 Cherry. They have been great and they look good too. I just wish that they made them with bright Nickel plating rather than the satin Gold, satin Chrome or black. The Cherry is a little unconventional, so they still look right, but I would not put them on my more traditional instruments. Those will keep their stock friction tuners just because for me the inconvenience is a small price to pay for beauty and I don't mind the friction tuners. Once the strings have settled in the tuners don't get a lot of use.
I agree that you should not use a standard, 2 flute drill bit because it will not follow the existing hole and is likely to grab and chip out. A piloted counter-bore type tool or stepping up with reamers works well in a drill press or vertical mill. Be careful breaking through. A wooden backing in a vice with the proper hole in it will help prevent any chipping out. I would not risk my instrument to save a few dollars, so if you lack the equipment and experience, you should probably have an expert do the job.