71 SG Body/Neck Joint Cracks - Repair And Restoration - The Looth Group

71 SG Body/Neck Joint Cracks

Electric Repair

71 SG Body/Neck Joint Cracks

Posted by Alex Wood — Wood Instruments on August 18, 2025 at 7:50 pm

It was only a matter of time before one of these arrived on my bench. The neck on this 71 SG Deluxe is caving through to the neck pickup cavity— In a similar fashion to what happens on old jr’s. Both sides of the cutaway have cracks that extend through to the pickup route and I can flex them easily. Problem is that the cracks are not straight and wander all over. I worry about being able to get enough glue in there because of this.

Thinking it would be better to route away the cracked mahogany and insert new tight fitting splines of mahogany that go all the way to the bottom of the pup cavity. This will also give me an opportunity to pitch the neck back slightly when I glue them in— because the guitar also has basically no neck angle to begin with. Over the years I’ve seen various repairs to LP Junior neck pockets etc, but nothing on an SG cutaway like this.

Anyone have any go-to methods? I guess I’ll try injecting and blowing in epoxy first? Have done lots of structural routing/ HS repairs and can definitely pull off option two— but I thought maybe I should head to TLG first for ideas on this one. Thanks in advance for anyone’s thoughts!

Alex Wood — Wood Instruments replied 7 months ago 2 Members · 5 Replies
5 Replies

Ian Davlin The Looth Group

Administrator
August 18, 2025 at 9:25 pm

I like the idea of using glue only first. It doesn’t take much time and it wouldn’t interfere with a more aggressive fix it fails.

How are you thinking about orienting the splines ? The one’s that I’ve seen that make sense run the entire width of the pickup cavity and slide up under the fingerboard a fair amount. Last one I saw I think was made out of ebony.

Maybe @patreon_5604352 James Roadman did it ? Possibly with a slitting saw on a milling machine.
Ian Davlin The Looth Group

Administrator
August 18, 2025 at 9:48 pm

Something kinda like this. RIP Joel !
https://www.instagram.com/p/CWAt6SgrmZZ/?hl=en&img_index=1

instagram.com
JW Guitar Restoration on Instagram: "1959 Gibson Les Paul Special - Neck and finish repair pt. 4/4 So I guess this is where things get a bit controversial. When and where is it ok or appropriate to introduce modern materials and techniques to a vintage instrument? The neck/heel and body surrounding that joint had been damaged more than once.. and while the material was all there, it was questionable how well parts were reassembled, how strong the joints were, etc. There were a few gaps as well. There was no practical way of opening up every joint, cleaning old glue and reassembling. One thing that did just need to go was the material in the neck pickup route. So we started by routing that out and exposing some of the neck tenon for the next step.. After much thought.. we decided to infuse the neck/tenon/body in the damaged area with structural epoxy.. and that probably would have been strong enough on its own. However, not knowing the full extent of the neck/body damage we decided to go one step further. We routed a few 1/8 inch slots across the front of the neck pocket. We milled some corresponding carbon fiber plate to fill these slots and tie the good, solid wood on either side of the neck to the neck and joint - so stability would never be a concern again. After vacuum infusion with epoxy - we filled the pocket with mahogany, re routed and filled in the tv finish everywhere we had removed it before and tied it in aesthetically with the original finish. Following which? You'd never know what lies underneath. If it ever gets dropped.. it's not going to break there again. Stability and sustain.. fantastic post repair. I think this is a rare case where going with an unconventional repair/technique is the right approach.. and possibly the only successful approach. . . #1959lespaul #1959lespaulspecial #vintagegibson #vintageguitar #tvyellow"
1,486 likes, 118 comments - jw.restoration on November 8, 2021: "1959 Gibson Les Paul Special - Neck and finish repair pt. 4/4 So I guess this is where things get a bit controversial. When and where is it ok or … Continue reading
- Alex Wood — Wood Instruments
  
  Member
  August 18, 2025 at 10:26 pm
  
  Thanks Ian! And wow that’s an awesome idea. I wonder if I could slot deep enough into the cracked areas. That Junior has a much smaller break area. RIP Joel, he was exactly who I thought of, thx for going and digging that up.
  
  I was actually thinking of routing away all the cracked/broken wood from the top, all the way down to the bottom of the pickup cavity and right out the side of the guitar/cutaway. It would be visible when finished but all new material. Would also essentially be huge relief cuts that would allow me to shift the neck angle slightly when I glue the new mahogany blocks in. The only thing is the guitar wouldn’t be any stronger than when it left Gibson. I think maybe a combo of these two methods could be the answer— if glue alone doesn’t work.
  - Ian Davlin The Looth Group
    
    Administrator
    August 19, 2025 at 5:59 pm
    
    I’m not sure what that would get you other than access to more gluing surface, which aint nothing, but unless you have some whack-a-doo grain orientation, isn’t why that broke in the first place.
    
    Also, slotting into the pickup pocket, under the fingerboard, makes your finish repair situation a ton easier. Unless you have a ton of experience with mahogany finish repair, those splines could easily turn into a shame spiral. But, if you don’t care how it looks or are confident that you can get to a good place aesthetically, I say have at it.
    - Alex Wood — Wood Instruments
      
      Member
      August 20, 2025 at 12:24 am
      
      I think you’re absolutely right Ian. I did some thinking today and some research on the kinds of slot cutting router bits I can get, and I’m confident that adding carbon fibre from inside the pickup route will be the strongest and cleanest solution over all. Thanks so much for your advice and thinking on all of this!

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