Bridge not staying centered; Because of lubed saddles, or something else?

[RoaringTwenties]

I have a CV jag with a staytrem bridge, .25 shim, and flatwound 12s.

Previously, there were no issues with the bridge staying centered in the thimbles. Since getting the guitar back from my tech recently (who was doing electronic work, no setup, though I know the bridge had to be removed), the bridge now ends up leaning all the way 'forward' (toward the pickups) in the thimbles, even when not using the tremolo. Right after I got the guitar back, I used Ben's nut sauce to lubricate the nut slots, string tree, and saddles ...I then realized I should not have lubricated the saddles, so I suspect this may be the reason the bridge is no longer staying centered. I tried to remove the lubricant from the saddle notches and strings with a q-tip and napkin (not sure how effective this was), but the issue is still there.

I guess I'm wondering what the best way to remove or "soak up" the lubricant would be? Or could there be another issue at play here? Is there something my tech could have done to potentially upset the balance? After a few minutes of playing, the bridge works its way from center to 'forward.' It's got 12s and a shimmed neck, so I wouldn't think lack of downward pressure / break angle would be the culprit. Plus like I said, previously the bridge always stayed and returned to center.

[RoaringTwenties]

Is it possible that the shim is causing this? I can't remember exactly because I've been tinkering with different things since I got it, but it's possible that this issue didn't exist before I shimmed the neck. Maybe there's too much friction on the strings and it's pulling the bridge forward?

[DeathJag]

This sounds like my recent problem that turned out to be the nut. Like yours my bridge kept ending up away from the tail. It turned out to be because the nut was too soft (it had the reverse pattern of the strings) and was holding the string when I hit the tremolo. When I eased back up the string was then sharp and the bridge was slightly towards the headstock.

Does yours change with trem use or just normal playing?

[RoaringTwenties]

This sounds like my recent problem that turned out to be the nut. Like yours my bridge kept ending up away from the tail. It turned out to be because the nut was too soft (it had the reverse pattern of the strings) and was holding the string when I hit the tremolo. When I eased back up the string was then sharp and the bridge was slightly towards the headstock.

Does yours change with trem use or just normal playing?

I removed the tremolo arm just to be sure, and the bridge still ends up toward the neck, even without tremolo use. It is a bone nut, fwiw.

[DeathJag]

Ho-kay then I got nothing! I'm interested to see how this goes. SOMETHING is pulling those strings!

[timtam]

The fact that the string has a slightly sharper angle behind the bridge than in front means that there is a net force vector pushing the rocking bridge not only down but also a little forward. The 'down' you want - the 'forward' you don't. Fortunately the high downforce that results from a 'sufficiently high' combination of string break angle (neck shim) and string tension (gauge) - along with natural, un-lubed string-saddle friction - is able to grip the rocking bridge and keep it in the neutral position (and to return it to that position after trem use).

So you want high string-saddle friction. But lubing the string-saddle contact points destroys that friction. Now the string no longer grips the saddle consistently, and the small forward force vector can push the bridge forward over time. And trem use, that should also involve consistent grip on the saddles by the strings moving the rocking bridge forward and back, is instead now inconsistent ... and so the bridge can end up anywhere (back or forward).

Maybe try flipping the saddles so the lubed section is downwards (edit: just remembered you have a Staytrem, with asymmetric saddles, but you may still be able to flip them), or using naptha to remove the lubricant (or soaking them in it). Also, change your strings, as they will still have lube on them.

Don't feel too bad. Fender once had online setup instructions for offsets that said lubing the string-saddle contact points was a good idea. AFAIK those instructions have thankfully disappeared.

For completeness, note that a fixed bridge has the opposite physics, where the string must slide easily over the saddle with trem use. So lube can sometimes be required on those bridges.

[jorri]

Most likely the lube. Shouldn't be on there anyway if you are using it rocking.

Alcohol and a tissue?

[Mitch T]

Exactly what timtam said
I had the opposite, a Squier bridge that wouldn't stay put despite heavy strings and a shim and a Staytrem fixed that issue without changing anything else.

[Todd Connelly]

To expound on what timtam said above, because of the steeper angle down to the trem and the resultant force vector. You don’t want the bridge posts centered in the thimbles when at rest. You want the break angle equal on each side. So the bridge needs to angle back slightly towards the trem when at rest.

Cheers…………………Todd

[timtam]

To expound on what timtam said above, because of the steeper angle down to the trem and the resultant force vector. You don’t want the bridge posts centered in the thimbles when at rest. You want the break angle equal on each side. So the bridge needs to angle back slightly towards the trem when at rest.

Cheers…………………Todd

If string-saddle friction is sufficient to rock the bridge all the way forward and back with trem use, it should be more than enough to keep the bridge in the upright/middle/neutral/centre position when static, despite the slightly forward-pointing downward force vector ... that results from the typically-unequal string angles off the front and back of the bridge.

Offsetting the bridge's resting position from the centre position would give the bridge a smaller range of movement in one direction before the posts hit the thimble walls with the necessary bridge rocking that comes with trem use. The bridge would have to be angled back a considerable way from the centre position in order to achieve equal string angles off the front and back of the bridge. If the bridge posts were to hit the thimble wall in one direction, then the string must lose grip on the bridge, and then the remaining string motion as the trem returns can no longer return the bridge to where it started.

So all in all, the straight upright/middle position is still the preferred position for the rocking bridge.

[Todd Connelly]

Really?! What are you doing to the poor thing? With normal trem use on mine, the movement is there but barely discernible. I can’t imagine what I would have to do to get the bridge posts to hit the sides of the thimbles. Oh well fair enough.

Cheers………………Todd

[timtam]

Really?! What are you doing to the poor thing? With normal trem use on mine, the movement is there but barely discernible. I can’t imagine what I would have to do to get the bridge posts to hit the sides of the thimbles. Oh well fair enough.

Cheers………………Todd

Luthier Gerry Hayes has also noted that some people have suggested that the bridge could be tilted back, although he was referring to having the posts actually resting against the back thimble walls. But understandably he says it's unnecessary. Such a bridge has nowhere to go with a trem arm pull up, and proper rocking is unavoidably disrupted.
https://hazeguitars.com/blog/setting-in ... or-mustang


Obviously I don't know just how far 'angle back slightly' means in your case, or exactly how much rocking motion you get with your typical trem use. But as I said, getting the string angles to be equal off the front and back of a bridge (as you suggested), for a bridge that is at an optimal height, would require the bridge to be tilted quite some way back. As one can see from Hayes' diagram above, the resting position wouldn't have to be tilted back far, before it would get quite close to the back thimble wall ... where contact would disrupt rocking/stable positioning. If the bridge were lower, then the geometry would mean that the bridge wouldn't need to be as far back to get equal front-back string angles. But then that low bridge wouldn't get the necessary string downforce magnitude as a higher bridge ... for string-saddle friction to hold the bridge easily in the middle position - which is what we want.

But if your setup works for you, that's all that really matters. I just don't think the physics require anything but an optimal-height bridge with a resting post position in the middle of the thimble's internal dimensions.

[jorri]

What i do is push the bridge toward the tailpiece so i rests on th thimbles.
THEN
give the trem a good upward pull, followed by downward one to get the bridge off the thimbles and get the trem into its resting position
THEN
tune, and put on the lock....because i only ever downbend.

[inkeye]

I had this problem with my Staytrem bridge on my Bass VI. I took a little sandpaper to each saddle, and scuffed up the saddle a bit. I have flats on my Bass VI, so maybe that's why it kept slipping. Also check your trem to see if the spring is depressing and that might also be part of the cause.