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SirDoh
01-26-2018, 12:49 PM
How standard are tuners?
I play Brazilian cavaquinho (a steel strung cousin of the ukulele with odd tuning for people who's lives aren't complicated enough). It has the classical style 2L2R style machines with plastic sting posts which were probably of ukulele stock.

My problem is that the steel strings are more sensitive than nylon so tuning is twitchy. I want to get a spare set and modify them so that they have a smaller diameter, which is a way of gearing them.

Can I just buy a set with confidence that they will fit correctly?

Graham Greenbag
01-26-2018, 01:16 PM
How standard are tuners?
I play Brazilian cavaquinho (a steel strung cousin of the ukulele with odd tuning for people who's lives aren't complicated enough). It has the classical style 2L2R style machines with plastic sting posts which were probably of ukulele stock.

My problem is that the steel strings are more sensitive than nylon so tuning is twitchy. I want to get a spare set and modify them so that they have a smaller diameter, which is a way of gearing them.

Can I just buy a set with confidence that they will fit correctly?

In my limited experience the short answer is no. Geared tuners usually have a 14:1 ratio but slightly finer ones are available. IMHO reducing the already small diameter is likely to give problems with the strings.

sequoia
01-26-2018, 07:49 PM
Tuners are sort of standard or not. There seems to be two sizes: the 10mm size or the smaller one. Go here to get bushings to fit your tuners holes:

http://www.stewmac.com/Hardware_and_Parts/Tuning_Machines/Tuner_Parts/1920s-style_Tuner_Bushings.html

Hope this helps a little bit.

Titchtheclown
01-27-2018, 01:48 AM
First I would try if lubrication made tuning smoother, less jerky. Both grease on tuners and pencil lead or talc or proprietary muck in nut slot.

I have not seen 2l2r in plastic you may have to either fill and drill or get a set of guitar tuners with the hope of mix and matching parts. If you try a local repair place they might have some broken classical guitar tuners that you can modify the posts of to fix.
The alternative is to go for broke on the ones you have. Fortune favours the brave.

SirDoh
01-27-2018, 07:01 AM
Forgive me. I my have mis-described what I have. Despite many years of toying with guitars and basses, I've never actually bought anything other than individual machine heads.
I have classical style tuners with the gear shafts made of plastic. They are about 9mm (3/8") in diameter. I think they have metal running through them. If I reduced them to 6mm (1/4") It would make them 30% more precise in their tuning. So my question is really how interchangeable are the parts from one set to another?

Of course, if its possible to install a set with metal shafts by bushing out the ends, that would work too. Is that ever done? Is that what Sequoia is referring to?

Joe King
01-27-2018, 09:03 AM
Forgive me. I my have mis-described what I have. Despite many years of toying with guitars and basses, I've never actually bought anything other than individual machine heads.
I have classical style tuners with the gear shafts made of plastic. They are about 9mm (3/8") in diameter. I think they have metal running through them. If I reduced them to 6mm (1/4") It would make them 30% more precise in their tuning. So my question is really how interchangeable are the parts from one set to another?

Of course, if its possible to install a set with metal shafts by bushing out the ends, that would work too. Is that ever done? Is that what Sequoia is referring to?

Classical guitar style tuners shafts are usually either plastic or ceramic on the outside with a metal shaft inside.

something like this:

https://images.reverb.com/image/upload/s--6uH14OW3--/a_exif,c_limit,e_unsharp_mask:80,f_auto,fl_progres sive,g_south,h_620,q_90,w_620/v1506087143/tqkcdyxnzmsu67fux6sv.jpg

If you want a thinner, metal shaft you are likely going to need bushings for each end of the tuner posts while using something like the tuners also for a slotted headstock but for steel string as typically used for Parlor guitars.

Like this:

http://img2.stewmac.com/product/images/990/Economy_3-on-Plate_Tuners.jpg

which are $10 per set from:

http://www.stewmac.com/Hardware_and_Parts/Tuning_Machines/Slotted_Peghead_Guitar_Tuning_Machines/Economy_3-on-Plate_Tuners.html

But I'm not sure if the holes will all line up.

Beau Hannam Ukuleles
01-27-2018, 11:02 AM
classical guitar (with the fat posts)= 10mm holes

All others have 1/4" posts. Bushings vary.

2 or 3 on plate are always 35mm from center to center, with the standard brands.

Titchtheclown
01-27-2018, 01:09 PM
Most of my thin metal posts have been 6mm the difference between 6mm and 1/4 inch is . 4mm which makes for a tight fit on the 6mm holes I always drill. I just went out and did some measurements on my cheap Chinese sets and indeed they varied from 6.0 to 6.25 mm which explains why I need to clear the 6mm holes I have drilled on all my ukuleles with a needle file occasionally when things get tight. The fact that I have built around 130 ukes and not noticed that before probably means you really shouldn't be relying on my advice;) . Reading the specs the Gotoh site shows a diameter of 6.32mm which gives you wiggle room on a 6.4mm/ 1/4inch hole. The regular bushings I have seen have all been roughly 8mm to 1/4inch so you may need to shop around to get a bushing to reduce from a 10mm hole to a 6mm hole which is why I suggested filling and drilling. Filling and drilling to a 8mm hole you then use the bushings Sequoia pointed to could make things neater.

It sounds though like you are thinking of keeping the back plate and swapping the shafts. Pulling apart a few of my cheap ones, they do look kind of interchangeable but close measuring found plenty of small variations between sets.

These look like they have 35mm between shafts
https://www.ebay.com/itm/2pcs-Ukulele-Tuning-Pegs-Keys-with-Cream-Button-for-Ukulele-4-String-Guitar/312024128787?_trkparms=aid%3D888007%26algo%3DDISC. MBE%26ao%3D1%26asc%3D20131227121020%26meid%3D98b3d 3e963dc43ecb9e7233a7971a731%26pid%3D100009%26rk%3D 1%26rkt%3D1%26sd%3D221448938368%26itm%3D3120241287 87&_trksid=p2047675.c100009.m1982

These have 25mm between shafts
https://www.ebay.com/itm/Guitar-Tuning-Peg-Machine-Heads-Tuner-for-4-String-Banjo-Ukulele-Chrome-Plate/181656392704?epid=571502459&hash=item2a4b909400:g:ES4AAOSw2s1UztZY




I will repeat my advice to lube first as what you are having difficulties with may be a product of jerky movement in the system rather than a gearing issue, a lot of ukes get made with no gearing whatsoever.

SirDoh
01-28-2018, 12:46 AM
Thanks for all the help guys. It looks like I will need to do a little research about what is available in the UK. Its a fairly expensive instrument, so I'd want to get it right before I start drilling. That might mean going up market on the machine heads.
http://ramavioloes.wixsite.com/rama/modelos-cavaco

There is no rush though. Its perfectly playable. Its not jerky to tune. Its just such a short scale, high pitched, steel strung, instrument, that even an 1/8 turn puts you way over or under.