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Need help on a Repair
http://www.luthiersforum.com/forum/viewtopic.php?f=10137&t=49492
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Author:  DanKirkland [ Wed Jun 21, 2017 9:41 pm ]
Post subject:  Need help on a Repair

So I have the usual suspect of a Gibson SG.

Headstock was broken some years ago, repaired, and now the glue seems to have completely given up and the entirety of the break is open.

I'm trying to figure out what was used before, there is a black reside on the entirety of the open grain. See the pictures below.

Image

Image

I have a few solutions. Before I do any cutting/splining I want to see if anyone knows what kind of glue may cause this. If I can just reglue it (hide or fish glue) then I'll do that to save my buddy some money. He said that it opened up after leaving it in the car (it was 98 that day).

If it was something like titebond, then I don't see many options other than epoxy or cutting in a really big spline/scarf to repair the area.

Any thoughts?

Author:  Hesh [ Thu Jun 22, 2017 4:36 am ]
Post subject:  Re: Need help on a Repair

Dan this complicates things that 1) it's opened back up and looks horribly contaminated and 2) it's a friend meaning, in our business.... that you can't charge what's appropriate if you are going to have to jump through your sphincter to repair it. There is also the added problem as well it's been broken prior and however the prior repair person was satisfied with the joint as-is is what you have if you attempt to reglue. Lastly, the fix didn't work and that's telling as well.

With all that aside IME this is a chop it off and make a new headstock situation. I would not trust the prior work to clean, fit, and reglue especially if this is a potentially valuable or coveted heirloom instrument.

We likely would not take it in and the work would be sands guarantee if we did anything beneath what we would consider to be a best practice such as making a new headstock, refinishing, etc. and that would cost big.... bucks for a busy shop like ours in both opportunity costs and what we would have to charge the client. And again this is a friend..... See I really do listen...;)

My suggestion is to be completely honest with the client and unless you have unlimited time available to you sometimes value and quality have a cost, friend or not this should be at least shared.

Oh yeah, in all of this pedantic mess is what you really wanted, no way I would trust that existing, failed joint clean out or not it has to go or this things going to be a headless horsemen again.

Author:  Chris Pile [ Thu Jun 22, 2017 8:10 am ]
Post subject:  Re: Need help on a Repair

In 40 years I have NEVER seen a joint that turned black. I wonder if it was contaminated glue, or someone added a color to the glue. It's WEIRD. I'd open it up and attempt a cleanup and reglue, and a finish touchup would probably be in order. The big BUT here? The job would be more expensive than normal, and NO GUARANTEE. Up to the client to risk it.

Author:  DanKirkland [ Thu Jun 22, 2017 8:52 am ]
Post subject:  Re: Need help on a Repair

Thank you gentlemen for the replies

Hesh wrote:
Dan this complicates things that 1) it's opened back up and looks horribly contaminated and 2) it's a friend meaning, in our business.... that you can't charge what's appropriate if you are going to have to jump through your sphincter to repair it. There is also the added problem as well it's been broken prior and however the prior repair person was satisfied with the joint as-is is what you have if you attempt to reglue. Lastly, the fix didn't work and that's telling as well.

With all that aside IME this is a chop it off and make a new headstock situation. I would not trust the prior work to clean, fit, and reglue especially if this is a potentially valuable or coveted heirloom instrument.

We likely would not take it in and the work would be sands guarantee if we did anything beneath what we would consider to be a best practice such as making a new headstock, refinishing, etc. and that would cost big.... bucks for a busy shop like ours in both opportunity costs and what we would have to charge the client. And again this is a friend..... See I really do listen...;)

My suggestion is to be completely honest with the client and unless you have unlimited time available to you sometimes value and quality have a cost, friend or not this should be at least shared.

Oh yeah, in all of this pedantic mess is what you really wanted, no way I would trust that existing, failed joint clean out or not it has to go or this things going to be a headless horsemen again.



Hesh, thanks for your reply. And I figured that this was one of those situations where cost quickly exceeds the value. We did discuss doing a headless conversion project (would be insane but also cool if it worked out) to turn it into something ala Strandberg.

I am with you on not trusting the previous glue joint, my thought is that even with something like epoxy the joint even with the long grain didn't hold and I do not want to have to resort to just regluing with permabond death glue (epoxy).

Chris Pile wrote:
In 40 years I have NEVER seen a joint that turned black. I wonder if it was contaminated glue, or someone added a color to the glue. It's WEIRD. I'd open it up and attempt a cleanup and reglue, and a finish touchup would probably be in order. The big BUT here? The job would be more expensive than normal, and NO GUARANTEE. Up to the client to risk it.


Same here Chris, weird part is that there's NO visible residue/chips/bits from the old glue. Even hide glue leaves residues of where it's been with small bits here and there within the joint.

I just consulted a friend who works for titebond, he informed me that some PVA glues (read the subtext of cheap/low quality) will turn black and fail if there's a contaminate within the container/dispenser that gets mixed with the glue. He said that things like rust, metal bits, and plastic dust can mix and cause the glue to be permanently destroyed, and the only solution if that happens is to throw out the glue.

EDIT: He just sent me another text and said that Titebond III also dries black on occasion (for many different reasons). But I don't think that that's what happened in this case.

So in the end, I think that whomever did this repair used a contaminated wood glue, either contaminated by keeping it in a dirty container, or using a dispenser that contained trace amounts of rust/degrading plastic etc... This caused the glue to steadily go bad over a period of time, and thus we have the headless horseman before us.

Author:  Frank Ford [ Thu Jun 22, 2017 10:07 am ]
Post subject:  Re: Need help on a Repair

In my opinion, splines are too often problematic, so I'd go with the "backstrap" overlay - it's sure, certain and solid with just enough flexibiity to handle pretty heavy shock loads in case of a future whiplash.

Here it is:

http://www.frets.com/FretsPages/Luthier ... erlay.html

Author:  DanKirkland [ Thu Jun 22, 2017 12:13 pm ]
Post subject:  Re: Need help on a Repair

Frank Ford wrote:
In my opinion, splines are too often problematic, so I'd go with the "backstrap" overlay - it's sure, certain and solid with just enough flexibiity to handle pretty heavy shock loads in case of a future whiplash.

Here it is:

http://www.frets.com/FretsPages/Luthier ... erlay.html


Frank, that is an excellent suggestion, I would have to figure out a way to do it by hand since I don't have a drill press/mill yet. Not impossible just challenging

Author:  Freeman [ Thu Jun 22, 2017 9:00 pm ]
Post subject:  Re: Need help on a Repair

I recently had a 12 string brought to me that had a similar broken headstock. It had been "repaired" with some sort of epoxy but they got a bad mix and it never really catalyzed. I was able to clean most of it out of the break, used a lot of denatured alcohol, but still felt that the break was pretty compromised.

Image

I reglued it with Titebond knowing that probably wouldn't hold, then grafted a piece of carbon fiber over the break as a spline. A Guild 12 has two truss rods - I had to put the CF over them rather than one each side of the single t/r like most splines.

Image

Finally I put a back strap on it much as Frank describes (using a Safe-T-Planer, that tool justifies buying a drill press)

Image

The hardest part was matching the original stain and finish

Image

I got to see this guitar the other day - it has been about 6 months since the repair and even with 230 pounds of string tension trying to break it open the repair is holding up fine.

Author:  david farmer [ Fri Jun 23, 2017 8:16 am ]
Post subject:  Re: Need help on a Repair

That's courageous Freeman! Good job.
I just declared one of those Guild 12's DOA for someone. I've never seen a design with less wood holding the head on. Your photo looks like you were through into the rod pocket. No?

Author:  DanKirkland [ Fri Jun 30, 2017 8:55 am ]
Post subject:  Re: Need help on a Repair

Freeman you did an excellent job on that! You have skills.

Just to follow up with this one, considering the cost of the instrument vs. the cost of the repair the owner decided to just leave it be and turn it into a wall hanger.

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