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I'm fixing up a 1956 Gibson LG-2 that looks to have been put away tuned to pitch. It's seen time in an attic or basement. It's kinda dinged up, but there's no sign of water or anything like that. It's kinda dry and some braces need to be glued, but the only cracks (2) look to be caused by impact, not by weather. The bridge was "lifting" and the top is bellied. As soon as I started to wiggle the saddle, the bridge came off (I had already removed the nuts from the bolts that are hidden under the marker dots-I didn't know Gibson ever did that!)


A couple of questions:
Does something like the Belly Reducer Cauls from Stewmac work? I know heat is used to reshape wood, but these things have a smallish footprint, and I wonder whether they would really work.

This guy wants to learn how to play (it was his father's guitar) so he can play and sing songs with his daughters. One concern I have is that even if I can get the top reasonably flat, it might just return to its bellied shape. I've read about the Bridge Doctor and I wonder if it would help. I wouldn't use it to get the bridge flat, just to keep it that way. Any thoughts? With the narrow bridge, I'd have to attach it between the string holes and the saddle. Is that a viable option?

Is there an easy way to get the marker dots and bolts out without any damage? Once I get the top flattened, the bridge will need to be shaped.

Any thoughts would be appreciated, and I'm guessing I'll have more questions.

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"Real guitars are for old people, Mr. Marsh."

Eric Cartman

First do no harm. Bridge Doctor is an atrocity of a duct tape bandaid, to be reserved for crappy instruments unworthy of anything else. Using one on an instrument like this would likely get you excommunicated from any luthiers' group, and possibly tarred and feathered if you attend any gatherings.

The belly reducer isn't much better in my opinion. Any time you force distorted wood and joint under heat back in to a position, when done you can rest assured that it will then be weaker than it was before the original distortion. Another temporary bandaid, with very high risk of the problem returning, possibly even worse this time.

I honestly can't see enough from the photos and camera angles to judge how bad the belly is, but often the best thing you can do is leave it alone and do nothing beyond regluing the bridge with a good proper hide glue joint. Tops belly a bit, and the repair community has been quite eager to bring them back down in the past. Standards and methods have evolved though, and today it is often preferred to take a less invasive route and not go nuts trying to flatten it out.

This requires some judgements to be made by reasonable appraisal and experience. First of course is appraising condition of the bridge plate and brace joints. If the bulge appears to be both drastic and at risk of progressing further, then work with the bridge plate and bracing may sometimes be in order. On most of these old Gibsons though, they were built with a pretty steep top radius to begin with, and tend to settle in to a fairly stable position on their own. It may look noticeably bulged at first glance, but often times a trained eye will be able to gauge it as likely quite stable, and best left alone.

A bit of reshaping can be influenced with the bridge glue joint alone, but I would advise against taking any drastic (or in the cases you brought up, potentially harmful) measures unless it can be verified such corrections are truly necessary. Perhaps a few more pictures, with careful lighting and angles to better capture the bulge you're concerned with, may help bring some more informed opinions from people here.

Tops can have bellies though, often reaching a stable state of equilibrium that is best left alone. A bit of belly isn't necessarily a bad thing.

As the the screws, they will often pop the pearl out quite cleanly with a bit of pressure or light taps. Resting the face of the bridge against a board with a hole for the pearl to exit through (careful alignment required) can minimize risk of wood tearout, though they will often come out clean with minimal force or risk. The pearl itself may crack on occasion, but this is easily replaced.

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Eschew obfuscation, espouse elucidation.

Thanks for the insights. It's good to hear your opinions about trying to reduce the belly and the tools I mentioned. I took several pics of the belly and that one shows it about as good as I could get it. The bridge was obviously being held on just by the bolts. I think a proper glue joint could help with the way it was pulling on the top. The bridge plate appears to be in good shape and is firmly attached. Your input kind of has me thinking that getting the top little flatter and reshaping the bridge a bit and gluing that up, then getting the loose braces glued back will offer the best solution without resorting to Red Green tactics. Thanks again for saving me that embarrassment.

I think you're probably right that this top has reached it's state of being. Once I get the bridge mounted properly, it should be pretty easy to set up. The neck angle is such that it won't need a reset (now or maybe ever-it looks really good).

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

I should add that if the glue squeeze out around the braces appears a crusty, rusty, brownish-red kind of color, you may be entering a world of new profanities as you attempt to glue one spot up, and three others pop loose. This guitar is right on the cusp of that era of adhesives, so you may be fine. That glue though, which I think may have been a resorcinol formaldehyde, can become notoriously brittle and weak. I've had to fully te race a few of these, and today I usually just turn them away.

_________________
Eschew obfuscation, espouse elucidation.

Cool. Thanks. I guess I'm entering the phase of learning what work to turn away...

This is for a friend, so between that and me wanting to get more experience and this being a pretty cool old guitar I'm going in, Cap'n. I sure hope I don't run into the rabbit hole you're talking about (although the bridge coming off so easy may not bode well).

Here's 2 more pics of the belly with a straight edge on top and a light behind:



Right now I'm leaning toward getting the braces glued, fitting the bridge and putting that back on. What are you thoughts on glue for the bridge (and braces, for that matter)? I see proponents for Titebond and for hot hide glue. Any opinions? There are some other cosmetic things, and new tuner buttons, but that's all pretty straight forward.

Thanks

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

As severe as that distortion may look, my biggest concern and focus would be on the bracing in front of the bridge rather than at or behind it. The bellying behind does not bother me so much as the collapse in front, toward the soundhole.

I would ensure the X-braces are secure all along, especially toward the neck side of the crossing, and that the bridge plate is secure as well. After that, distorted as it may appear (and from what I can glean from the photos), I would be inclined Ned to glue the bridge on without any major efforts to reverse the bellying behind it. The heavy crown typically found in these tips can leave them quite durable, even after some settling.

Again, just going from experience combined with what I can gather from the photos (which is never as thorough as a first hand view), but that's my gut feeling here.

As to glues, it depends to some degree on what was originally used. For this era, for braces, a Titebond / PVA will typically be just fine. For the bridge, I would definitely advocate hide glue though, if for no other reason than the creep resistance across such a narrow footprint.

_________________
Eschew obfuscation, espouse elucidation.

I think an "in-person" look would confirm what you said. When I first saw the guitar with strings still on it, I was more concerned with the dip in the area in front of the bridge. Really, my main motivation for reducing the belly was to bring that area up, not so much to bring the belly down. Several days of clamping and gentle humidification has had little effect. That, and your advice leads me to believe that leaving it and securing the braces is the way to go.

Thanks again for your advice, and any more words of wisdom would be welcome.

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

What is the condition of the bridge plate?

The bridge plate looks really good. I just noticed that I neglected to mention that one of the braces that's loose is the X-brace on the bass side of the upper bout. I also just noticed (kind of a "duh" moment) how much the area in front of the bridge comes up when I push that brace into place.

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"Real guitars are for old people, Mr. Marsh."

Eric Cartman

I wouldn't worry at all about the belly behind the bridge, most old Gibsons that sound good have some belly. Mine ('56 J-50)probably has twice that much.
The loose X-brace is a much larger concern.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

OK, the braces are glued, and so far holding nicely. You can bet I'll have my fingers crossed when I tune it to pitch.

Now, and sorry if this is a newb question, but do I have to do anything to this area to prep it for re-gluing? There's a bit of old glue that I'll pick out, but I'm referring more to the roughness of the surface.


Part of me thinks that anything I fill it with is just something that's not the guitar top that I'm gluing the bridge to. When I put the bridge on and clamp it, it looks to sit flush. Should I just clean it and glue it? I've already cleaned the bottom of the bridge.

Also, remember that it will also be held in place by the 2 honkin' bolts on the bridge (that's a...I say that's a joke son)

Thanks again, guys

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"Real guitars are for old people, Mr. Marsh."

Eric Cartman

I would want a better (smoother) surface than that - also need to clean the bottom of the bridge off. For some more information that might be helpful, check this discussion on pg 2 for what I did on an older Martin based on advice from some of our pros.http://www.luthiersforum.com/forum/viewtopic.php?f=10137&t=46907&start=25 Not saying you need to go to that much trouble, I would wait to hear from one of the more experienced repair folks.

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Steve Smith
"Music is what feelings sound like"

I'll second what Steve said. A smooth gluing surface holds much better than a ragged one. I can still see what I think is some glue residue on the top as well, make sure you clear that out before you do any gluing.

Thanks, guys. I'll get it smoothed up before I glue it. I just wanted to get some guidance from those who have gone before me. I'll get it done and I'm sure I'll have more questions before I'm done.

The tuners will be next. I've got to replace the buttons, but they feel really tight (granted, this is me turning them with no buttons on them). Is there a way to loosen them up? If need be, is there a way to take them apart? They're on a strip with sealed backs. I see the little tabs, but will I do more harm than good by opening them that way? Here's a pic


Thanks again

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

The tuner buttons made for putting on old tuners are easy to use and effective. I got mine from StewMac. You just hold a soldering tip on the shaft and gently push the button on. Unless the shafts are really bent those old tuners usually respond great to oil. Don't open them up until you give them a chance with lube and buttons.

Sounds like words to live by

Thanks

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

If they're really stiff, you could inject a little solvent in the lube holes, cover holes and shake, let them drain on a paper towel, then warm them with a heat gun to evaporate the solvent. Let cool, then re-lube.

Alright, here's the clean bridge area:
I'm just posting this to say thanks. I was tempted to just smooth it up up a little and glue the bridge on, but Steve and Dan guilted me into taking it a little further. I'll get a patch cut and glued in in the next couple days.

I'm new to this, and you guys reminded me that the only way to get better at doing good work is to do good work. Even as an amateur, I try to look at my work through the eyes of someone seeing it ten or fifty years from now. I'd rather them not say "Who the hell did this, and what were they thinking?"

Thanks

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

Bill, way to go. That's pretty much my philosophy too.

_________________
Steve Smith
"Music is what feelings sound like"

That bridge foot print still looks a bit rough to me, much better though. Also I usually abandon the original bolts in the bridge design when fixing these bridges. Perhaps that is not the authentic vintage way of doing it but that design is a bad one.

And just also to add fwiw, I have not tried a Thompson Belly Reducer but I have heard nothing but good things about them.

Here's the patch before sanding it level:

I got a little "focused" at this point and neglected to take any more pics.

Here's the finished guitar:


The tuners were still pretty tight after putting buttons on and lubing the crap out of them. Of course I didn't really know just how tight they'd be until I strung it up. Since he and his daughters were so excited to get this thing, I gave it to him as is and told him we could do the tuners later if he wanted.

It turned out pretty nice. It was pretty grimy and had paint dings form sitting uncased for so long, and that all cleaned up really good with patience and polishing compound. There were a couple cracks that I didn't try to make invisible, but I got them repaired and filled.

Thanks for all your help, guys! I'm sure future projects will come with new questions.

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

Nice job - bet they were happy to get back a player!

_________________
Steve Smith
"Music is what feelings sound like"