Tuners slipping

[crankypants]

1989 Fender Precision Bass Plus with the fancy "Schaller deluxe die-cast tuning machines"

The bass slips slightly out of tune easily and often, and tuning accurately is iffy.

Should I tighten that screw on the main gear?

I don't want to damage anything as it's all original.

 

[Real Soon]

Is it happening on all of them?

I could be wrong, but I think the fit under that big screw is something like a square peg & square hole, meaning tightening won't do anything to help... unless you check the screw and it's currently loose. If it's already snug, don't tighten it further!


Traditionally, players of wooden-peg instruments like violins/violas/cellos will tune upward to reach the target pitch, and never downward. The reason is, when tightening things, one can know that all the parts are snug due to increasing tension, while something might be slightly "caught" when you're tuning downward, later slipping and making the string go flat.


Also, a known culprit of tuning issues is the nut. If you've changed strings and your new strings are even a different brand at the same gauges as the last set (and for a tight-fitting nut, even the same brand strings!), you could end up having the nut slots grab at your strings, making tuning a sporadic hassle. Might be worth investigating further before taking tools to the tuning machinery, IMHO.

 

[Geri O]

Is it happening on all of them?

I could be wrong, but I think the fit under that big screw is something like a square peg & square hole, meaning tightening won't do anything to help... unless you check the screw and it's currently loose. If it's already snug, don't tighten it further!


Traditionally, players of wooden-peg instruments like violins/violas/cellos will tune upward to reach the target pitch, and never downward. The reason is, when tightening things, one can know that all the parts are snug due to increasing tension, while something might be slightly "caught" when you're tuning downward, later slipping and making the string go flat.


Also, a known culprit of tuning issues is the nut. If you've changed strings and your new strings are even a different brand at the same gauges as the last set (and for a tight-fitting nut, even the same brand strings!), you could end up having the nut slots grab at your strings, making tuning a sporadic hassle. Might be worth investigating further before taking tools to the tuning machinery, IMHO.

One thing you can try is to take a pencil (with graphite) and “write” down inside the string grooves. Make a good coating of the graphite in the grooves, then reinstall the strings and see if they are more stable.

The problem I had that led me to this solution (with help from the usual good guys here) was that I would tune my bass, then a few minutes later, the strings would go a little sharp. The temporary fix was to tune slightly flat, then snap the string and it would go to its in-tune state (if you guessed correctly on how flat to tune the string before you snapped it).

The eventual fix for me was to have my guitar guy widen the nut slots. He measured the rather heavy-gauge strings I used (at the time, but no longer) with a micrometer and widened the string slots just enough for the strings. That fixed my tuning problems, although I still use the pencil in the string slots just cause I wanna...

(Even though I recently went down to medium-gauge strings, the nut slots are still fine for those strings)

You can buy graphite lube just for this purpose. But the pencil works well enough for me.

Check into this before you dig into the tuners. And ditto on dropping the pitch below the target pitch, then tune up to it. I even tune pianos with that method.

Good luck...

 

[WillyW]

Has it done this since 1989?

Is it strung correctly?

Are the gear screws snug?

What has changed since the problem started?

 

[Zooberwerx]

Has it done this since 1989?

Is it strung correctly?

Are the gear screws snug?

What has changed since the problem started?

From my experience, the actual machine head is the least likely suspect. The problem usually resides in the string path, including:

*Lack or witness points (tuner post, nut, bridge saddle).
*Too-few strings wraps.
*Twisted string.
*Poorly cut nut slots which either bind and/or result in false contact points.

Riis

 

[RSBBass]

From my experience, the actual machine head is the least likely suspect. The problem usually resides in the string path, including:

*Lack or witness points (tuner post, nut, bridge saddle).
*Too-few strings wraps.
*Twisted string.
*Poorly cut nut slots which either bind and/or result in false contact points.

Riis

Exactly!

 

[Lownote38]

I suspect the nut, or the string retainer hanging up the string when you tune. Then, when you play harder, the string lets loose from either of those parts. When you tune, do you hear little clicking sounds as you're tuning up? Acoustic guitars are notorious for having this issue, and that's the telltale sign.