Peaceful tuning, Pacifica 112

Hello again!
It's been over a year since my last post (Pure Drumming). I started Electric Penguinland as a series of notes-to-self, to write up things that were difficult to discover online. I'm glad people have found the odd thing I've posted useful, so I'm picking up with the article that I was planning to start last year with: replacing the tuners on a Yamaha Pacifica.

This is my occasionally-modified Pacifica 112. The tuners it comes with are fine, but they were getting old and a bit worn, so there was travel on the knobs and the pegs themselves could wobble a bit. Actually replacing the tuners (or machine-heads) is not terribly difficult, the trick is finding out what to replace them with. Along the way we'll go over some of the different options. If the following seems like a shaggy dog story at least it might save someone from going up the same garden path.

Original tuners

This is a pre-112V model (maybe 2007?), with 6-a-side modern tuners. The 6-a-side simply means all 6 are on the same side of the headstock, unlike a Gibson or many acoustic guitars with have 3 tuners on either side. All 6-a-side tuners in a set will be the same, in 3-a-side set three of them will be left-handed and the other three right handed (the tuning key coming out of one side or the other). "Modern tuners" are a compact cylindrical shape with a flat side for the tuning key. This is sometimes called Gotoh style after the Japanese company who popularised them (and confusingly make lots of other types). The other major type are square and sometimes called traditional or vintage (or Grover, again a company who make lots of types).
The other thing to notice is there's no obvious screw holding them in. What is? It turns out there are two small guide pins under the straight side. Trying to make sure I got ones that would fit this is what caused most of the headaches. A year on I think if I did this I might just drill the holes for screws, but that's not what happened. More on this later...

More precisely

These pictures show one of the original tuners being measured up. The tuner holes are a standard 10mm. The distance between the pins (10mm) and from the pins to the tuner peg centre (a bit less than 10mm) turn out to be typical for this pattern of tuners.
(Except Fender American standard tuners, which have a longer distance between the guide pins and the tuning peg. These are also more rectangular when looked at from behind.)
Chinese companies like JinHo and Metallor make this pattern. Getting hold of them is not very hard, but often stock photographs don't show whether or not there is a tab or pins which makes things tricky (the answer is usually tab). Part numbers tend to be WJ805, WJ807, J802, J805 and J807 seem to be common for guide-pins. If you see one of those without the 8, for example, WJN-03, it's probably not the pin version.

The golden ratio

One thing to consider is tuner ratio, which is where I got a bit stuck. Most cheap tuners are 15:1, meaning you turn the knob 15 times for every turn of the peg. The higher that number is the more precise control you have. Those WJ part numbers are Wilkinson locking tuners. These can come in 19:1 ratios, which I was keen to use, and so spent a while trying to hunt them down in this guide-pin form.
In short it doesn't exist, Wilkinson (or at least their UK distributors, JHS) seem to have discontinued the guide pin model. I managed to get hold of a set of the remaining ones. The normal (screw-tab) EZ-lok are now all 19:1, but the guide pin versions when they arrived were 15:1. So if you're determined to stick with guide pin versions (to avoiding drilling any holes is really the only reason), it'll have to be a 15:1 set. In the UK Northwest Guitars do a set, and Guitars and Woods sell a Wilkinson non-locking model which is probably 15:1. 15:1 is fine, you can easily tune a guitar with 15:1.

Changing tune

Actually changing the machine heads is simple. Get a spanner, unscrew the nut on the front side of the headstock and then pull the tuner out the back. Then just put the new tuners in (lining up those troublesome pins) and screw in the new sleeve, tighten with spanner. Done.
The alternative is to accept you're going to have to drill screw holes, this opens up the option of any tuner with a screw tab. They're not all in the same place—high end tuners like Grovers and Hipshot notably put the tab in a slightly odd position—but most are 45 degree and at least you have a choice. You could get the Wilkinson EZ-lok (in reality the design doesn't 'lok' very well, but it does let you use staggered heights), but these days I prefer wheel locking tuners, there are inexpensive ones from Axetec and Axesrus among others. And happily those come in 19:1.
However, for the moment the Wilkinsons are staying on.

Anyone wondering if there's something odd about this last picture is right. It was so tricky to get these that I had to buy button ones. I tried putting the old knobs on (so, one hex knob in the picture), but in the end decided I actually like the buttons. So one good thing has come out of this!