12-string Setup

[Southpa]

Every guitar is unique in my opinion. I've done lots of troubleshooting and repair work in my day but recently, I have rethought some aspects. Setting up acoustic guitars is almost guess work. A friend brought over his new acquisition, a Yamaha FG-412SB (SB = sunburst). The strings were waaaaay off the body, the treble side of the nut was too low. He was under the impression that the nut slots on the treble side had to be built up with superglue and baking soda, something he heard from someone else. Heres the first rule of thumb, when someone who doesn't work on guitars brings you a guitar to fix and they tell you how it needs to be done ...DON"T LISTEN TO THEM! Find out for yourself. I rapped the nut off and found that one side of the neck (where the nut sits) was lower than the other side. A simple shim fixed that.

The bone bridge saddle was way too high. I carved a good 1/8" off the bottom and plunked it back in. Now the guesswork part. A 12-string neck has a lot of tension when fully tuned up. When you put a string on and find that the action/relief is reasonable before tightening and tuning up all the strings you will find that the resulting action after tuning will be too high, too much relief. When all that tension is applied the neck is gonna bow. So what ya gotta do is tighten the truss rod so when a string is first laid down it just bottoms out on the frets. And you can only tighten the truss rod on a 12-string when the strings are slack. Otherwise, you could break something. Tighten up all the strings and the neck will bow just perfectly. Playing the guitar before was quite a workout, my hand was sore after only a few barre chords. Now its effortless.

I don't know why they make medium and heavy gauge strings for 12-string guitars. My friend is a heavy handed player and he has never owned a 12-string before. He already bought a set of medium Elixir's for me to install (33 bucks!). I said forget it, use lights and nothing but lights on a 12-string if you want a playable guitar.

just an edit. My friend picked up his guitar and he was very happy. He flipped me a 50 dollar bill and I offered to make change, but he said keep it. Work done: total fret levelling/crowning, bridge/nut reshaping and setting, cleaned up the hardware with my trusty dremel and wire wheel attachment. Total of about 2 hrs work, so 25 bucks an hour. Not bad for working at home.

Edited September 12, 2006 by Southpa