Gibson J 50 structural repairs

[Andrew]

Okay, this is going to be a long one so bear with me. I may introduce new questions to the thread as Ive got quite the list here, and a whack of pics...

Im repairing an old J 50 for a customer, and this is the list of issues thus far with asterisks by the ones im most concerned about right now, and accompanying questions:

- all the back braces are loose, as in dancing around inside the guitar loose
- all the centre joint lining on the back is loose (3 are right off, the other 2 will be removed and reglued)
* theres a nasty dent/puncturish thing in the side (bass i believe). This is one of the more difficult issues, though less structurally significant as some. The split on the inside of the guitar is much longer than out, and its very apparent that no reasonable amount of force will press the outer surface back flush
* another (maybe the most) worrying issue - the tail block is half loose. Do i inject glue and clamp it, or finish removing it and risk that delicate end grain seam between the sides?
- theres a hole from an input jack
- theres a piece missing from the back, and 5 other cracks, some fine, some not
- the pickguard is shrinking and curling, one small crack in the top as a result
* the finish is in horrid shape: checking everywhere, chips everywhere, worn to bare wood around the pick guard, the neck is blistered all over, and im pretty sure someone added finish to the top and bridge with the strings on. At this point, should i be at all concerned about the vintage when considering refinishing the whole shibang?
- the frets are way worn, like everything else
- the bridge plate is glued solid still, but doesnt appear to be doing its job. Replace?

Erm.. Thats the worst of it for now. One more question though, should i adjust the neck angle while the back is off by shifting the thing, or would itbe better to wait and remove the neck after the body is back in order.

[Andrew]

Well its not that the bridge plate isnt doing its job, its just not doing it all that well. But considering the size of the plate and the factory glue job, its doing okay. I get the feeling the guitar will get played, as this person's father gave it a lot of hard love, and itll be going back to the father as a gift.

Im not sure of the year yet, im still searching serial numbers. The serial on it is Y6333 23.

Regarding the finish this was more of a general question. I never had any intention of refinishing, more just shoring up my own opinion about leaving it. Im barely equipped to refinish and space is at a ridiculous premium in my shop.

More or less i just like to hear different opinions on these things. You never know what youll learn.

[Paul Hostetter]

It's better to date a Gibson by the Factory Order Number (FON) than the serial number. 

How did you determine the bridgeplate was not doing it all that well? What does that mean?

[Andrew]

Its job. Its got quite the cup to it.

[Paul Hostetter]

I'm sorry, cup? I think it's time for a photo. This doesn't tell me anything useful.

[Andrew]

Cup as in what often happens with flatsawn boards. Ill try for a decent pic tonight.

[Paul Hostetter]

- all the back braces are loose, as in dancing around inside the guitar loose

Glue them back after cleaning the old glue out.

- all the centre joint lining on the back is loose (3 are right off, the other 2 will be removed and reglued)

There you go.

* there's a nasty dent/puncturish thing in the side (bass i believe). This is one of the more difficult issues, though less structurally significant as some. The split on the inside of the guitar is much longer than out, and its very apparent that no reasonable amount of force will press the outer surface back flush

With the back off, making perfectly-fitting inside and outside cauls to press it all back shouldn't be difficult.

* another (maybe the most) worrying issue - the tail block is half loose. Do i inject glue and clamp it, or finish removing it and risk that delicate end grain seam between the sides?

It seems open enough to clean out old glue and do it over again in place.

- there's a hole from an input jack

Ugh. Sorry about that. Inlay a plug and try and make it a clean, good match. 

- theres a piece missing from the back, and 5 other cracks, some fine, some not

Close them and reinforce them.

- the pickguard is shrinking and curling, one small crack in the top as a result

Not uncommon. Probably best to put on a new guard which will precisely cover and replicate the original—after the guitar is all back together. Flattening celluloid potato chips is possible, but thankless and not always successful.

* the finish is in horrid shape: checking everywhere, chips everywhere, worn to bare wood around the pick guard, the neck is blistered all over, and im pretty sure someone added finish to the top and bridge with the strings on. At this point, should i be at all concerned about the vintage when considering refinishing the whole shibang?

No. Leave it as-is. It acquired that patina honestly. Honor it history and cut your losses at the same time.

- the frets are way worn, like everything else

After it's all back together, refret it.

- the bridge plate is glued solid still, but doesn't appear to be doing its job. Replace?

Not ordinarily. What leads you to believe it's not doing its job? A photo could be helpful. You can reinforce the area around the holes if needed, without replacing anything.

[Andrew]

I really dont think pressing the puncture back to shape with cauls will work in this case. I think whats happened is one side of the puncture has slipped under the other somehow so its sort of overlapped itself, if you can understand what i mean. I really cant get a good pic of it. Same with the bridge plate, i dont have the lighting to get a picture that shows the degree of cupping on the bridge plate. It certainly wasnt glued all that well though (mind you the joint is still solid). Some parts are totally devoid of squeeze out, which i know because the squeeze out was never cleaned on anything involving the top.

Just for clarity, what is your reasoning in gluing a pick guard after the back is back in place? Im thinking the concern would be the weight of the clamp distorting things..

[Andrew]

Reading my original post, i realise my phrasing re the finish would lead one to believe i have half a mind to strip it 'n spray it. Thats not the case here. I just dont communicate with other humans often enough :)

[Eric Steven Johansen]

OK so I'm slowly getting a clearer picture on this one. It's a 1953 Gibson J-50 we are talking about, a fairly valuable guitar on the vintage market. It has a lot of sentimental value to the customer and, from what I can see from the pictures, it is in restorable condition. First off, if the back is removed it's a no brainer to replace the bridge plate, as it is the equivalent of your cars tires, getting the brunt of the wear and tear from those pesky string balls, and so easy to replace when you have access. Regarding the side dent/break, usually some gentle manipulation can achieve realignment to allow Paul's glueing process, highly recommended by the way, and, I would add just a little moisture to the affected wood before clamping. If you want fool proof, add a veneer patch inside, to back it up. Regarding the pickguard, there are some really good two sided glue sheets available, I use Stew Macs, that require no clamping of the guard to install, and are easily removed in the future, should that be needed. Better photos of all the important issues would be great, if you can make that happen. Best of luck with this one as the result could be a fantastic instrument.

[Andrew]

Heres a pic of the bridge plate with light and a straightedge to show the warp/cup. Its maple and a little undersized, but the holes are in okay shape considering. About the side dent, ill certainly try making the cauls to clamp it back in shape, but i fear even with a padded outer caul the pressure required might do further damage with the way the wood has folded on/overlapped itself. Its a hard one to describe.

I have those two sided adhesive sheets by 3m stew mac sells and they are great (nice for sharpening fids w microabrasives too), but are they suitable for adhering a pickguard to bare wood? I believe Frank used carpenters glue on one of the repairs on frets.com. How well does the yellow stuff really adhere to plastic?

[Eric Steven Johansen]

I would definitely replace the bridge plate, as I said there's no easier time then now. On bare wood under the pickguard guitars, it's my practice to apply a few sealer coats of shellac to the area first, and I've thus far had no adhesion problems to either the guard or the top. One caveat is the fit of the guard to the top, make sure you're not trying to hold down a severely warped guard or failure can occur. 

[Andrew]

The guards not too badly curled. Can they be pressed flat with a little heat maybe? Or do they tend to have a 'memory' of the warp?