Tilting bridge on Martin S1

Blank Williams

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IMG_2807.jpgHi all. So I recently purchased a used Martin S1. One of the first things I noticed was that the bridge seemed to be excessively tilting forward and there appears to a bit of dipping between the bridge and the sound hole. I’ve checked the braces as best I could but it’s difficult to get a good look. I’m wondering if this looks excessive, if you can even tell by the photo? Thanks!
 
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That does look wrong, as if the top has warped under the strain of the string tension. If the bridge secure? Can you fit paper under the back edge of the bridge? My next question would be how is the action? The good news is that it looks as if you have plenty of saddle showing if you need to reduce the string height.

The only way I know to affordably fix something like that is using the Bridge Doctor, a gadget that fits inside the instrument and pushes up on the top from underneath.

https://www.youtube.com/watch?v=nxJpM4xoXg0

But I'm not sure if they make them for ukes.
 
Yeah it’s really noticeable in person. So far the bridge has not lifted from the body. When I loosened the strings it went away for the most part, so yeah it’s definitely from the string tension...
I’m pretty bummed since it sounds great. The action isn’t bad and I also noticed that there is still plenty of saddle left. The action could come down a bit, but currently it’s perfectly playable. Thanks for the response.
 
This is a common issue and has been discussed at least a couple of other times in the last few months in the UU forums. Consensus seems to be if the dip is less than a couple of mm and the bridge is secure (cannot slide a piece of paper under any of the corners) and the intonation is still good (notes ring true on all the frets) and there are no cracks in the soundboard, then most people are willing to live with it and just enjoy the instrument.
 
A small amount of lean, dip and bulge is perfectly acceptable, even normal, but that looks to be at the limit of what I like to see. It might not get any worse. If it is playing well, I'd leave it alone and just enjoy the uke.

John Colter
 
Ok. As long as it doesn’t get worse I can live with it. I haven’t checked the intonation, but so far it plays and sounds great. I keep all my solid wood instruments in a hard case with a sound hole humidifier. I’ll keep an eye on it though. Luckily it’s not a terribly expensive uke, but man I love the way it sounds way better than the couple of other S1s I’ve played in the past...
 
I have removed such a belly from old guitars by placing it in a plasticbag with an elelectronic humidifier, keeping it at around 85%. Then jacking up the top between the soundhole and the bridge a little by little and pressing down the bulge behind the bridge.
When it is (a bit over-)corrected, I leave the guitar in the bag for around 2 weeks, to let it return to room humidity.
The wood will bounce back a bit, but it works and looks like it will take another half century, to go as bad again
 
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I have removed such a belly from old guitars by placing it in a plasticbag with an elelectronic humidifier, keeping it at around 85%. Then jacking up the top between the soundhole and the bridge a little by little and pressing down the bulge behind the bridge.
When it is (a bit over-)corrected, I leave the guitar in the bag for around 2 weeks, to let it return to room humidity.
The wood will bounce back a bit, but it works and looks like it will take another half century, to go as bad again

Interesting..how do you "jack up the top"?
 
Interesting..how do you "jack up the top"?

If the OP's problem is caused by too-dry storage conditions, then adding humidity will cause the top to swell and fix the concaved top.
The issue is, there may be other damage from storage not so obvious.
 
I don't want to make much of a judgment based on a picture...but here is my opinion:
So long as the bridge isn't lifting, I'd say don't worry about it. Assuming the frets are level, so you can indeed lower the action without issue, that should take a bit of tension off the bridge in addition to making it play easier. I don't think that's necessary either, at this point, if you like it as-is. I wouldn't put high tension strings on it. If the bridge starts lifting someday, or even if it came off it could be repaired then.

I've had hands on some Martin OX, their HPL ukes, and they have some pretty severe lean...more than I like to see...but I've never heard of one lifting or popping off. The lighter the build, the more vibrant the instrument. I got to play on an S1 for a while that I thought was really nice. Really good uke I thought.
 
Yeah I bought it used and just got it the other day. I have no idea if the previous owner/owners kept it humidified or not. Right now I’m just using an oasis sound hole humidifier. Like I said, when I loosened the strings the bridge seemed fine after a day of no tension. If I had a small mirror I’d be able to get a good look at the braces, but unfortunately I don’t have one. I’m really thinking it’s something internal. But I’ll see if a week or so of keeping it humidified helps.
 
Interesting..how do you "jack up the top"?

StewMac has some mini jacks to do this. But they are difficult to use in a small instrument as a ukulele, maybe get a child to jack it up. I've 3D printed some for myself but you can also lay a piece of wood over the top and clamp the top up to that piece of wood.

I haven't tried it yet but I just bought a tool intended for lifting a door or window in place while fixating it. It's a small cushion with a handpump attached.
 
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I agree with Besley the lower bout top seems to be warping upward below the bridge and lower.

I suspect that there may be a brace that has come loose or broken. If you start hearing a buzz or rattle from inside the body you'll need to get the brace reglued or replaced.

I had something like this happen to one of my ukes due to over humidifying it. A ripple warp in the soundboard formed in the lower bout just below the bridge. I removed the humidifier from inside the body and replaced it with an older Humidpak, inside a cover, that I placed in the case by the neck heel. I also placed an InkBird Hygrometer inside the body to measure the RH. The initial reading was 67%. It took 2 weeks to lower it to 45%. The warp was almost gone. It smoothed out completely after two months.

Do you feel any undulations on the back?
 
My eyes could be playing tricks on me, but the back does seem slightly rounded or very subtly bowl-like. I’m pretty sure it’s supposed to be flat but of course I could be wrong. It’s funny this uke was listed as “mint” condition, but I noticed the bridge almost immediately. I have spoken to the seller about it and he was very cool and assured me he’d make it right if I wanted. I’ll likely keep it, as it’s pretty much everything I want in a soprano minus the issues ha! The last S1 I played was so dull sounding but felt bulletproof, this one is so lively...
 
My eyes could be playing tricks on me, but the back does seem slightly rounded or very subtly bowl-like. I’m pretty sure it’s supposed to be flat but of course I could be wrong. It’s funny this uke was listed as “mint” condition, but I noticed the bridge almost immediately. I have spoken to the seller about it and he was very cool and assured me he’d make it right if I wanted. I’ll likely keep it, as it’s pretty much everything I want in a soprano minus the issues ha! The last S1 I played was so dull sounding but felt bulletproof, this one is so lively...
Having some radius to the back is done on purpose usually.
Here's a thread right here on UU from some builders:
https://forum.ukuleleunderground.com/showthread.php?118495-Should-the-back-on-a-tenor-uke-be-arched
 
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