Neck Heel Crack Repair

[Dave Domizi]

Hi All,

 

Thanks for taking the time to offer some help and advice with a structural repair on an electric neck joint.

 

I have a 70’s Gibson ES 325 in the shop that came in with a neck solidly pulled out of set/gap at the back of the neck heel. It was frozen solid like this and may have been for years, as the guitar had been in a closet for a long time. The neck shows heavy finish checking/cracking around the neck joint, and long finish checking cracks running lengthwise on much of the neck, though it’s only severe around the last 8” or so by the joint. Despite the appearance of the neck joint having been broken, I was unable to get the joint to move at all by pulling the neck around, or by applying some clamping pressure, so it seemed really locked in its position.

 

I steamed out the joint, which I now believe may have been a terrible mistake. As the joint got close to soft/loose, the steam revealed and pushed out of a long crack 6-7” that ran from the joint up the back of the neck. This caused the smaller outer section of the break on the outside back of the neck to swell/twist, and it is now sprung and very resistant to clamping. I can get a good bit of the crack closed by clamping, but not all, and the dry clamping has slightly compressed the out heel area already. I worry that the sprung/twisted nature of the break will make it difficult or impossible to glue solidly.

 

I need advice as to:

- Should this crack be glued and clamped as is, and then the remaining gap filled? If so, what kind of glue and procedure would be best, given the sprung nature of the break?

- Are their better, more proper repair procedures for this type of crack? I've thought of some possibilities, but they seem REALLY undesirable. Should the split be routed out and the wood replaced? Should install and then inlay over/hide a large wood screw through the heel to hold the area together as solidly as possible? It strikes me that these other less desirable options would also include some tough refinishing work that may be beyond my ability.

 

So, I really need some expert advice. I may be out of my league here, so I’m also interested in finding out for the customer if another expert shop could take in this job and, if so, what would be involved and how much it might cost the customer. I can be reached by email and by phone at 706-549-1567. If you miss me, please try to leave a number that I can use to call you back.

 

Many thanks for any help and advice. Have a great week!

 

Dave

[Mark A. Kane]

OK, I'll stick my toe in the water slowly on this one, but I may pull it it out quickly. I'd first rule out any routing or screwing. This, in my opinion, tears the lid off the can of worms. If you can get some movement of the crack, gluing is probably the best option. Assuming it won't close completely, I might approach it with the intent of closing the crack as much as it will go without forcing it or using undue clamping pressure. I would, while it's clamped, investigate the possibility of cleaning out a portion of the glue close to the top of the crack so as to leave some room for filling with a lacquer melt stick. This way, you're not asking the glue to do too much and risking the crack popping open at a later date. If you are careful, the lacquer stick may take care of the finish issues completely. Do some dry runs first!!!!!

 

Good luck!

[Dave Domizi]

Hi Mark,

 

What would your glue of choice be for this job, epoxy? Any recommendations on a source for "rainbow" colors of lacquer sticks? LMI sells only black & clear, and Stew Mac sells a whole kit for over $100, but no individual sticks.

 

Many Thanks,

 

Dave

[Mark A. Kane]

I would not use epoxy. I like LMI's instrument glue for it's working time, among other things. I'd rather have a small open crack to work with if the clamping pressure required to close it is too great. Not having the guitar in front of me, take this next statement under advisement: If the dimensions of the neck are not greatly affected (cosmetically) I'd be more concerned with the structural integrity. It sounds as though it is likely to be a repair that is visible in any case, barring some serious finish work. I know their are craftsmen on frets.net who could make this crack disappear and would consider anything less as an unacceptable solution, but you have to decide with the customer what is acceptable cosmetically, structurally, and monetarily. I'll now repeat myself by reiterating: Not having the guitar in front of me, take this last statement under advisement.

I sourced lacquer sticks from Woodworkers Supply a decade ago. Good luck!

[griff]

Make sure you've cleaned out the crack best you can. Using padded cauls and an iron C-clamp slowly try to close the crack (slowly). Has the crack twisted away from its mate so that any attempt to fill would be uneven and uncomfortable (it doesn't look like it from the photos)? I think epoxy tinted black would be the best option here, it would both secure and fill while not requiring perfect clamping pressure (if the crack won't close tight, no amount of AR or hide glue will hold), plus it will buff out to a shine to match the lacquer.

[Jeff Highland]

In your last picture it looks like there is some blue grey substance in the crack, that may be stopping it closing.

also you have introduced a lot of moisture into the interior of the neck, it may take time to dry out.

[Dave Domizi]

Hi Jeff,

 

I'll give it plenty of time to dry out. That's actually just background light coming through the crack in the last picture, the crack itself is clear of everything except the pull splinters.

 

Many Thanks,

 

Dave

[Dave Domizi]

Hi Griff,

 

I think that it's not twisted too badly, just V-ing apart, so a fill will likely be relatively smooth.

- What's your method for tinting epoxy? Can I just mix in some liquid dye like Stew Mac stuff, or would the water content mess things up? I also have black pigment powder, and I can always powder ebony.

- Has it been your experience that epoxy will buff to a shine? I've usually found it to come out a bit duller, so I'm reluctant to leave it at the surface.

 

Many Thanks,

 

Dave

[Howard Klepper]

I

 

f I understand you correctly, clamping the crack closed (as far as you can) is compressing the heel so that it would end up narrower than its mating surface on the body?  That has to be avoided.  The plus side of this is not having to get that crack closed, which may not be possible if the steam swelled the wood fibers in the crack.

 

Fortunately, there is a heel cap.  These are your friends.  I would remove it, put a dowel at an oblique angle to go across the crack (not a screw), and replace the cap.  Then fill with whatever; it doesn't much matter because a refinish of the heel and its adjacent body area is needed.  After you glue the neck back in, you need to sand the neck/body junction smooth, so that any mismatch from the slightly expanded heel is eliminated.  Fortunately, the burst goes to black in this area.  If you look at Gibson instruments such as mandolins, you will find that the darkest parts of a sunburst turn out to be right where you need them to be for hiding flaws.  I don't think that is by accident.

 

If you are unable to refinish this area and blend it it to the rest of the neck and body, then you need to punt.

 

Looking at the crack on the end grain is a good lesson in how wood tends to split--right on a radius of the tree.