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PostPosted: Fri Aug 23, 2024 7:20 am 
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I have a guitar in with a screwed on neck like an Eko/Epiphone (no heel)
It's 50 years old and owner's first guitar, so it's a bit sentimental, only worth maybe $600 max. and I've done a lot of work for him so I'd like to help.
The top has delaminated at the top of the neck block.
It only has a small area glued each side of the neck pocket, so there has been a lot of stress on a small area.
With string tension, the neck rises, the top bulges in the neck block area and the action is very high.
The delamination is uneven, not just one layer, up and down a bit though the top over the neck block's length.
Can I try working 24 hr epoxy into the delaminations, clamping it down 24hrs, and then epoxying a wooden fillet at each side of the neck block and top meeting point?
I know epoxy in normally a no-no, but it's only thing I can think of doing without an expensive re-topping?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.


Last edited by Colin North on Sun Aug 25, 2024 6:45 am, edited 4 times in total.


These users thanked the author Colin North for the post: Kbore (Mon Aug 26, 2024 4:40 pm)
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PostPosted: Fri Aug 23, 2024 8:01 am 
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Brazilian Rosewood
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Epoxy would be fine for a guitar like that. Most of those heel-less epis of that vintage have not survived because they were a terrible design and poorly constructed.


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PostPosted: Fri Aug 23, 2024 11:55 am 
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Old Growth Brazilian Rosewood
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We've never attempted to relaminate a laminated top so I really can't say. We have had the conversation with many clients about guitars with sentimental value that they still can be kept, hung on a wall, whatever and that repairs don't have to be made. But I know you know that and I understand that this is a good client and you are a good guy for wanting to help Colin.

Thinking out loud here: What about clamping things up and positioning the box so that you can employ gravity and a quality this CA to wick into the laminates once they are clamped in place? Perhaps use that white cutting board material as cauls since CA won't stick to them. Could be a God awful mess too if too much CA is deployed.

Pics would be helpful too I am not sure I completely understand what this looks like.



These users thanked the author Hesh for the post: Kbore (Mon Aug 26, 2024 4:41 pm)
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PostPosted: Fri Aug 23, 2024 2:45 pm 
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Cocobolo
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Least if you retopped it they'd end up with a good guitar?


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PostPosted: Sat Aug 24, 2024 1:24 am 
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mike-p wrote:
Least if you re-topped it they'd end up with a good guitar?

I think the neck attachment system is the basic problem, string tension is held mainly by 2 lengthwise strips of wood ~3/16 wide (top of neck block) glued to a laminate top.
It may be that the glue joint on the bass side has failed first, putting as the stress on the treble side, where the glue has held but the laminations just couldn't take all that stress.
I'll try to get some pics today.
Not the best design to start with as Barry said.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.



These users thanked the author Colin North for the post: Kbore (Mon Aug 26, 2024 4:41 pm)
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PostPosted: Sat Aug 24, 2024 8:45 am 
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I should wear my glasses all the time!
The top was not actually delaminated, just some wood had come away from the top of the neck block with the glue
Propped up the top with a stick between UTB and a back brace to open the gap a little, then with some PSA abrasive on a pallette knife cleaned up the area, top and neck block, work araldite ultra in there with the knife, clamp and check there's squeeze out both sides.
Job's a good'un probably, but just in case, I'll be epoxying in about 6.5 cms of triangular section mahogany between top and neck block sides butting up against the UTB to help take the string tension.ImageImageImageImageImage

Sent from my moto g(50) using Tapatalk

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.



These users thanked the author Colin North for the post (total 3): Kbore (Mon Aug 26, 2024 4:43 pm) • Hesh (Mon Aug 26, 2024 5:17 am) • SteveSmith (Sat Aug 24, 2024 12:02 pm)
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PostPosted: Sat Aug 24, 2024 2:58 pm 
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Koa
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Pictures help. I don't see a delaminated top, I see a top that's broken free of the rim and neck block.

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PostPosted: Sat Aug 24, 2024 3:00 pm 
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Pictures help. I don't see a delaminated top, I see a top that's broken free of the neck block.

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Peter Havriluk


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PostPosted: Sun Aug 25, 2024 6:48 am 
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phavriluk wrote:
Pictures help. I don't see a delaminated top, I see a top that's broken free of the neck block.


I did see that, when I had my glasses on - see my last post

phavriluk wrote:
Pictures help. I don't see a delaminated top, I see a top that's broken free of the neck block.


I did see that, when I had my glasses on - see my last post

:geek:
:geek: :roll:

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.



These users thanked the author Colin North for the post: Kbore (Mon Aug 26, 2024 4:44 pm)
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PostPosted: Mon Aug 26, 2024 5:23 am 
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Old Growth Brazilian Rosewood
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Not what I thought either I thought that the top wood itself on a laminated top instrument was delaminating.

Looks like a great fix Colin, nice work.

Regarding retopping a guitar in the US for an established shop to retop an acoustic guitar if the customer was charged what it costs to do properly expect a $2 - 3K bill. It's a big job with finish matching and blending, reinstalling a neck and more. Most shops we know who are busy would not even take it on not because of complexity but because of opportunity costs. We have many, many gigging musicians who need fast turnaround so the show can go on and have to maintain some bandwidth for them at all times.

Of all the things we will do including neck resets and more retopping a guitar is a bigger job than anything else for a repair shop short of a full on restoration which at times is less involved than a retop too.



These users thanked the author Hesh for the post (total 2): Colin North (Tue Aug 27, 2024 7:53 am) • Kbore (Mon Aug 26, 2024 4:45 pm)
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