Bridge lifting on Acoustic Bass

[sdgrfan]

I recently came into a good deal on an acoustic bass, a Takamine EG512C. Everything is fine with it except for a small bit of lifting on the rear of the bridge. The lifted part is about 1/8" across the width of the rear of the bridge. It doesn't seem to be pulling up the top. So I have two related questions:

1. With new strings, to prevent the bridge from coming up further, would it be helpful to tune down, to, say, D-G-C-F? Or won't drop-tuning affect this much? Is this anything to worry about?

2. If this is something to worry about or will get drastically worse at standard tuning, what type of repair charges might I be looking at?

Thanks for any and all help/recommendations.

 

[202dy]

When the bridge begins to lift it needs to be fixed.

The bridge does not pull up on the top. The bridge on an acoustic is an integral part of the bracing system that keeps the top flat.

When properly strung, the ball ends of the strings bear against the bridge plate. If the ball ends are bearing against the bridge it can cause the bridge to lift. It can also cause wear in the holes that could result in more expensive repairs.

Down tuning will affect the entire system from the standpoint of the amount of "belly" is in the top. It will have no affect on bridge lift.

Repairs: Depending on what's wrong, the construction of the instrument, and how it is finished, it may be as simple as cleaning, gluing, and clamping. Otherwise the bridge must be removed from the top, the surfaces prepped, followed by glue, cauls, and clamps.

This general information. It is impossible to diagnose this problem better without more data.

 

[walterw]

The bridge does not pull up on the top. The bridge on an acoustic is an integral part of the bracing system that keeps the top flat.

When properly strung, the ball ends of the strings bear against the bridge plate. If the ball ends are bearing against the bridge it can cause the bridge to lift. It can also cause wear in the holes that could result in more expensive repairs.

agreed, except in this case where the string balls are through the bridge itself pulling sideways rather than anchored under the top pulling up. (another reason why i don't like pinless bridges on acoustic instruments).

this thing also has two bolts securing it to the top (under that dot inlay just visible in the photo) so at least it's not gonna come flying off or anything.

 

[202dy]

agreed, except in this case where the string balls are through the bridge itself pulling sideways rather than anchored under the top pulling up. (another reason why i don't like pinless bridges on acoustic instruments).

this thing also has two bolts securing it to the top (under that dot inlay just visible in the photo) so at least it's not gonna come flying off or anything.

New photo. And you're absolutely right.

It might be light and reflection, but there appears to be a gap in front toward the treble side. My guess is that the bridge should be removed and reglued.

At first glance it looks like an Ovation bridge. Takamine and Ovation are sister brands. No surprise that there is some design bleed between them.

Generally, I like the string-through bridge. It minimizes rotation so tops remain flatter. There are no pins to lose. Don't have to repair damage in the bridge plate or string holes due to lack of string installation technique. On the other hand, the end of the bridge and the tops can get abused from sloppy handling during restringing. Nothing's perfect.

 

[megafiddle]

The bass end of the bridge still looks to be in perfect contact (the end facing in the photo)

Is the bridge lifting, or just warping upward at the rear edge?

Or possibly the top is uneven directly behind the bridge?

Acoustic tops do tend to roll towards the neck.

-

 

[sdgrfan]

Thanks for all the responses, good people. Just for clarification, here is a bit more info and another picture. First, the treble side of the bridge is as attached and flat as the bass side is, despite the way the picture looks. Here is another picture showing the "lift" at the strings. Is it possible that this is Tak's "design" to keep the string balls and strings from scraping the top? Or is it really starting to lift? If so, what kind of price range would I be looking at to have a pro luthier glue/reattach it?

Thanks again.

 

[202dy]

The bridge is lifting off the top. It needs to be repaired.

It is not a design feature.

Remove, prep, and reglue will vary. The reglue itself should be less than a night's pay. New strings and any other work is extra.

 

[walterw]

The bridge is lifting off the top. It needs to be repaired.

It is not a design feature.

+1, but i wonder if on this $600 new instrument it would really be worth all that, since the bolts should mean it's not going to really go much farther or actually come off. if it was bought new this would be a textbook warranty repair situation, and tak would probably just replace the bass and stuff this one into the wood chipper fargo-style.

i'd expect a couple hundred bucks to re-install that, considering the bridge itself will have to be made flat again (steam-bending? sanding?) and there's probably a bunch of thick poly top finish under there that should have been removed in the first place for proper wood-to-wood contact (probably why it failed).

 

[mongo2]

Return/exchange it.

 

[walterw]

Return/exchange it.

If this is still an option, big +1.

 

[Rebop]

I've done this repair at least a dozen times in the past year or two. Most of the time, the bridge is glued straight to the finish without a wood to wood bond. This is a design flaw. You would need to sand the bridge dead-flat again otherwise it will crack if you try to force it back down with clamps (also remove all the finish where the bridge sits). This bridge design is ridiculous but at this price point I don't expect anything less.

 

[fhm555]

I also have a tak ACB with the same bridge and same slight lift. I've been told i could glue and clamp it and it would be fine, but i'm thinking i'm gonna take it to a pro just to be safe. I don't mind trying new things on electric, but big boxes with strings just seem better left to a professional.