The Perpetual Guitar Thread

Backstop

Ars Legatus Legionis
32,853
Subscriptor
An image search shows that there is a plug in the top of the bridge. That plug hides a machine screw which helps hold the bridge down. The nut and washer have vibrated loose. You’ll want to reinstall them. Sounds like time from some fresh strings!
For stuff like that, is it a bad idea to use some Loctite/Permatex Purple on the threads? I would imagine it will just vibrate off again the more it gets played.
 

Cool Modine

Ars Tribunus Angusticlavius
8,783
Subscriptor
For stuff like that, is it a bad idea to use some Loctite/Permatex Purple on the threads? I would imagine it will just vibrate off again the more it gets played.
LUTHIERS HATE THIS ONE SIMPLE TRICK!

Tons of acoustic guitars have screws/nuts like this, right? And it generally isn't a problem. I wouldn't jump straight to the threadlocker, but would reinstall with proper torque first. You want it tight, but not so much that you're crushing/damaging any of the wood involved.

But if you've got that nut nicely snug and it still loosens up over time, using a gentle threadlocker seems reasonable. I've got Vibra Tite VC3 and use it where I don't want to use the standard blue locker. The VC3 dries into a gel consistency, and they specifically describe it as vibration damping, adjustable, removable, and reusable. I haven't used the purple, but it seems like a good option.