Requesting basic Gibson LG- repair/maintenance opinions

[Andrew H]

Hi everyone. Just joined and this is my first post because I recently became owner of a fairly neglected 1964 Gibson LG-?. I've put in the requisite "too many hours" reading on the internet and it's answered a lot of questions but I'm posting about a few that remain .

I have a specific goal of doing basic improvements to make it the best instrument it can reasonably be while preventing continued degradation. To that end, I’ve already repaired a face crack, ordered a replacement wood bridge for the plastic junk bridge, ordered a thin pick guard blank rather than buy a vintage replacement.

Some questions I still have that I’m hoping to get help or confirmation on:

——-Finish is very worn on the face. Under the bridge is the only original finish left— thick crackling resin of some sort. There is glue remnants under pick guard and finish but appears more like a thin hand rub oil type. I’d like to chemically strip with mild chemical to prevent damage to the binding, then seal with real shellac. There are water marks and maybe mildew; priority is to treat the wood as well as possible, secondary is to alleviate that neglectful water and sun staining. I’d really appreciate input on what the mildest effective stripper is for a guitar in this condition—

——Face has bowed a lot, but it played well before I removed bride, so I think I’d get a JLD bridge doctor if only to prevent further warpage. I checked braces and they are all glued well still and warped along with the face. Goal is to not have a cave-in but from review it sounds like I could use the bridge doctor to do minor adjustments as well as prevent further warp.

—- I’d get or more likely make a bridge saver plate from brass.

——One thing I’m still confused on— serial # has it as a 1964 but it has X-bracing, which from reading seems like it would make it an LG-3 or B25-N. But the pick guard was screw on and the glue pattern looks like a sort of teardrop like I’m seeing on LG-0 models. I guess some previous owner could have changed bracing and then some other previous owner alternated between storage in damp closet and leaving it in the sun. My goal here is to know what model it actually is and then never think about it again instead of wasting a few hours on the internet every few months when I get curious.

I think that’s it. I’m open to suggestions though. I would be shocked if I actually have already thought of all sensible maintenance and improvement! The tuners are neither original or great, but it is nice that they look vintage. If there are standard high quality vintage looking tuners for not-too-much I’d swap them while I’m doing all of this other work. By trade I’m a bass player and my dad was luthier (yes, I should have paid more attention back then) so I’m not directly familiar with details around these old guitars but I’m familiar with a lot of the concepts around the work.

Much gratitude in advance for any input.

[mirwa]

Pictures?

Steve

[John Arnold]

An LG-0 would have a mahogany top. Assuming a spruce top and original X-bracing, it could be an LG-2 or B-25. With no finish except for under the guard and bridge, it would be hard to say it was not an original sunburst. Also, the red dyes used on the mid-1960's Gibsons tend to fade on exposure.

I’d really appreciate input on what the mildest effective stripper is for a guitar in this condition—

I use a paste type stripper and keep it off the plastic binding and rosette. Most any stripper that dissolves nitrocellulose lacquer will also dissolve celluloid binding and rosettes, since they are essentially the same material.

Face has bowed a lot, but it played well before I removed bridge,

FYI, Gibsons are constructed with a radius on the tops. I assume you mean the top is bowed in the bridge area, which is not uncommon on the plastic bridge Gibsons.
Instead of a bridge doctor or PlateMate, I would prefer to flatten the top in the bridge area with a combination of heat and moisture. While the laminated bridgeplate can often be repaired, I prefer replacing it with a solid maple one. That will facilitate the flattening. A properly glued rosewood bridge will also help keep the top flat, since the bridge acts as a brace. This is one extreme example where using a thick, laminated plate and screwing the bridge down is a bad idea in practice.

[Andrew H]

I think this sums up the remaining troubles

https://www.flickr.com/photos/188971...posted-public/

https://www.flickr.com/photos/188971...posted-public/

https://www.flickr.com/photos/188971...posted-public/

https://www.flickr.com/photos/188971...posted-public/


Thanks for info so far! Much appreciated.

[charles Tauber]

I suggest there isn't enough finish left on the top to bother with a chemical stripper. I'd use a cabinet scraper and then sandpaper, which would make quick work of it.

As for the rest, pretty much what John said.

[mirwa]

It actually does not look too bad, can you do a distance shot of the bridge plate and bracing amd the guitar itself.

I suspect someone has modified the top braces from that supplied photo, afterwe confirm, suggestions can be made to flatten and or reshape the top accordingly.

Removing the finish is a pretty easy job on that one, just get some 220 grit and scuff sand with the grain until the surface comes clean, avoid oversanding, that is sand the bare minimum amount as you have no idea how much it has been sanded previously and it does not take much to destroy a top. When I sand a guitar I actually map out the surface first of the thickness before starting.

If any finish is tough to come off, use a metal scraper or a razor blade with the outer edges blunted.

Check the humidity inside the guitar from the photos it does look dry.

The rosette is an easy fix, make a back up ring internally for it and then cut and fill a new piece in place.

The bridge plate I would make suggestions after a distance photo of the inner bracing and "current plate"

Its a great start you got there, could be a great guitar again

Steve

[Andrew H]

https://www.flickr.com/photos/188971...posted-public/

https://www.flickr.com/photos/188971...posted-public/

Thanks for the input so far. It's all very helpful. Here are two more views of the interior. I did notice it has an actual "LG0" stamp in it. Mystery solved (facepalm). The bridge plate is a a piece of solid wood, not as hard as maple though. It's run underneath the bracing though-- looks tough to swap out for anything. Lots of glue in those pictures on the braces! I've steamed wood in other settings and seems like no big deal unless I over-do it and end up with all the glue joints coming apart.

So with LG0 stamp but x bracing it's likely as Steve suggested- post factory improvement.

Cabinet scraper and sandpaper makes a lot of sense for the face. Rosette repair makes sense too. Pickguard easy enough to make as well.

So only actual question at this point is best method for flattening and/or stabilizing face. I assume with aftermarket xbrace added, I don't know if it's hide glue or elmer's-- wrong glue would be an impediment to some more normal repairs?

Thanks so much, loving this forum. Less than 24 hours after post I'm down to only one uncertainty as to future action. Looking forward to posting "after" pictures some day!

[John Arnold]

Mahogany top is an LG-0. Original bracing was ladder, with a long bridgeplate. That is why the bridgeplate extends past the X. It has been cut off, just not enough for a proper X-brace job. The finger braces are a bit tall, IMHO. At the very least, I would trim those down to the height of the X-braces.
A bridgeplate replacement would be a bear, considering that the X-braces are on top of it. I would probably heat press the bridge area, then repair the bridgeplate by filling the pin holes with CA and maple dust. You could add a thin hardwood overlay over the holes for durability. I usually make these about 5/8" wide by about 3" long, or shorter if the X-braces are narrowly spaced. 1/16" thick is sufficient.
A more extensive repair would include removing the back and rebracing the whole top, including the bridgeplate.
Like I said before, a glued on rosewood bridge will add a lot of stability to the area.

[mirwa]

Originally Posted by Andrew H

So only actual question at this point is best method for flattening and/or stabilizing face. I assume with aftermarket xbrace added, I don't know if it's hide glue or elmer's-- wrong glue would be an impediment to some more normal repairs?

If that was my guitar or I was asked to fix it, I would pop the back off, steam the braces off, clean it all up internally, rebrace it either lattice or x, up to you and then put the back on again.

Visually vee newest pictures, I can see loose back brace, lots of glue mess on the sides.

It would benefit immensley from back removal.

Steve

[Andrew H]

Thanks again for all the input. Seems like I have two sensible paths to choose from. I'm leaning towards popping the back and getting to work on everything but I should think through if I have the time to follow through in the near future or if I'll just be making a shelf full of guitar parts until I truly have the time. I'd think there are risks too that all the glue is wrong variety-- and that I could do all the work to gain access but not be able to steam off anything? Maybe I should test for whether it's hide glue--

Off the top of my head, hide glue test could be rubbing a small bit of very hot water on one of the exposed glue messes and see if it dissolves at all.

I'd think it if its hide glue that there would be some handy heat assisted metal blade approaches to removal too? Like soaking a few thin blade construction knives in 200 degree water at tougher spots and alternating between heated ones? BUT I don't want to make assumptions about 55 year old wood. I'd rather do nothing than wreck it.

[John Arnold]

If not hide glue, it may very well be white or yellow glue, which can also be disassembled by steaming.
At the worst, you may have to carve out the old braces, which is not all that difficult with the back removed.

[Andrew H]

I removed the back. Pretty sure it was the least friendly kind of glue, 90% slow, no popping off for this one! Same with the bracing, steam softened the braces more than it softened the glue joint. The old cut bridge block was the only thing that came out fairly easily, with a little work it separated at the joint and not the grain.

https://www.flickr.com/photos/188971...posted-public/

https://www.flickr.com/photos/188971...posted-public/



Even with the messy back removal, I see that the bracing cut out for the bridge makes it an extremely weak bracing ("noodle bracing"?), and could account for the major face warp. That will be nice to make good and strong.

I think I'll leave other braces alone if possible though? Every brace removed is risk of pulling wood out of the face piece? If they're situated correctly and glued extra strong maybe I've got all risk and reward by redoing those. There are no weak joints with the existing glue.

After that I'd set up for steaming? I'd guess I just need a simple flat jig that I can clamp too and then I'd squeeze it to that in increments over the course of a week or three? Probably start the jig now while I still have to get new braces together?


Other than that, I guess at this point I'm doing things "by the book"? Matching existing diagrams for x bracing and shaping some new braces, maple bridge plate per the x bracing diagrams. Sounds like some labor but nothing too mysterious.

Are the black spots in the body from humidity? They look a bit like bathroom mold. Does dilute Oxalic acid work for that sort of cleaning or is that too harsh? Guitar's health is more important to me than its looks, so if there's no safe cleaner I'll leave it be.

Thanks for all the input.

[Andrew H]

Guitar all buttoned up. The basic take-away is 1)I have a great sounding guitar now! and 2)I have a lot more respect for how much skill and experience it takes to be good at this work. I think it would have gone a lot better if the previous "improvements" weren't done with carpenter's glue, and I think someday I'll be warming up my hide glue and resetting the back piece with a lot more clamps, or somebody else will be resetting it with a lot more clamps, knowledge, and experience. But the new bracing, bridge plate, and bridge, have done wonders for the tone. It's a bit weak on the bass, but has lots of great character throughout the midrange, which is great for me. As a bass player, I don't like guitars that take up a bunch of space down there.

Thanks again for the invaluable input. I definitely felt more and more like an idiot ruining a guitar until I finally tuned it up and played the first chord on it.

Thanks!

[mirwa]

Did not see the replys, removal looks good, any chance of photos of new bracing

Steve

[ClaptonWannabe2]

Somebody else modified that bracing before the OP, right?

I think I see old lines where ladder braces were?

Is/was it common to x-brace OVER a bridge plate? I am a newb by this boards standard, but I've never seen that.

Thumbs up OP for the work. What is your background? You come into this website like you are new to this, but you tackle some pretty advanced steps on a vintage guitar.

A. Are you a cabinet/fine furniture maker?

B. Are you cheap (cough) frugal? In which case, again thumbs up. I can do some basic auto maintenance. My car is dripping some powersteering fluid. I am not taking apart my own power steering. LOL

I agree with what someone said. That top finish is near non existent. Just sand it off and start over. I think I would do an "antique" finish. There are too many bruises on that face to put brand new IMO. Let those bruises show, because they are gonna show anyway. Sanding to remove everything would be sanding through the top at some point. OR it would be paper thin.