Tuning Gear Problem

[Randy Linam]

I have a pair of Gotoh tuning gears on my LM600 mandolin. One of the gears (the 1st D) will turn normally, then become very hard to turn and then go back to normal.

Any guidance on how to correct this problem would be much appreciated.

[High Lonesome Valley]

Take a look at the post while turning without the string on, see if post is bent.

Also, if this is an exposed gear, check the gear for tangs or other obstructions, maybe file the defect out.

Otherwise, it's a replacement the tuner(s).

[bart mcneil]

I am guessing of course, but if the mando has ever been dropped and that tuner mechanism or tuner knob shaft was bent that will often cause the problem mentioned.

If every mechanical part seems to function well while not under tension then i would investigate the tuner shaft itself Again it might be bent (less likely but possible). try using a dry lubricant on the tuner shaft as it enters the wooden headstock. Sometimes binding can occur in that area,

The next step would be to remove all four strings and remove the tuner mechanism from the mando. With if off you should easily be able to determine where the problem is.

it might also be possible that the hole in the wood for that tuner shaft is out of alignment with the tuner shaft itself, Less likely but possible. In that case I wrap sand paper around a knitting needle or large nail, etc and sand the hole a little just to barely enlarge the hole.

But if the problem is in fact a bent tuner shaft or a problem with the gears. I would guess the whole mechanism should be replaced.

Go to frets.com for excellent info on trouble shooting and repair of tuners.