Soundhole Crack Warped

[Jeff Perkins]

I've got an old Gibson SJ Deluxe in the shop. It's got a number of cracks on the soundboard which I'm repairing. But, the wood from one of the cracks from the soundhole is warped. You can see it in the pictures. My question to you guys is, "How would you flatten it back out so I can line it up to glue?" I'm thinking slow pressure over time with some form of humidity. But have any of you guys run into this before, and if so, how did you flatten the top back out?

 

[griff]

I think I'd do this with the neck removed, the added surface area would allow for larger cauls to help flatten and align the separation. Additionally, you would want to use oversized cleats to help keep it from re-opening (the crack will be under pressure after the repair until it gets used to its new place). Remember that a warp of that degree means the braces have let go underneath...repairing those will help return things to right.

[Jeff Perkins]

Yeah, obviously the braces have let go in those spots. But, the owner doesn't want to remove the neck. That was my first suggestion. So I'm looking for a way to do it without removing the neck. Yes I'm going to cleat it. I don't have any of those small heating "blankets" that LMI sells. I wondered if any of you use anything similar to do the same job?

[Joshua Levin-Epstein]

Jeff,

 

Try loosening the pickguard. I am pretty certain the pickgurad (and those guitars have a lot of pickguard)  is causing the warp.

 

Joshua

[Jeff Perkins]

You're probably right. How would you loosen it without damaging it. When I've removed them before with a hairdryer, I always wind up warping it. Any tips?

[Rob Mercure]

Jeff. Your customer doesn't want the neck removed but how about just the fret board?  While this would entail a whole new set or processes the neck would remain on the instrument and you'd have acess to repairing and flattening the table.  But, in general, this might be one of those "I'll have to pass this repair up as you will not let me apply established and effective repair proceedures.  As such it's warranteed until the shop door threshold!"

 

Rob

[Joshua Levin-Epstein]

Not to speak with absolute certainty, but I would assume the pickguard is already warped from shrinkage, and that caused the crack. It is possble the pichguard is affixed directly to the wood (via solvent, like Martin) so you need to release the tension.I might try the hairdryer and a thin knife. Another possibility is you soften the glue (or whatever) under that edge of the pickguard, clamp everything in place and see if it stays close to where you want.

 

Joshua

[Chris Rochow]

I have had good luck over the years with using 2 metal plates to sandwich the warped piece, after some slight dampening  of the wood. To one side (underside) adding some heat to the plate.. let set overnight. It may take a few times... it'll work. Gentle pressure at first, then each repeat increase the clamping pressure.

[Paul Verticchio]

Hi Jeff.

 

Looking at your photos, it appears as if that neck has some real condition issues.  The frets are poorly seated and it appears as if there's a slight twist to it.  You ought to include a re-profiling of the FB and a re-fret job in your estimate. I admit that the perceived twist may be an optical illusion in the photos.

 

Gibson acoustics from that era are not good sounding guitars nor were they built well. They definitely are not sought after by collectors. If I were removing the WAY too big & thick pickguard, I'd use a little hairdryer heat and a flexible tapered spatula to lift it. A reasonable bit of tear out from the removal will not compromise or devalue the instrument.

 

Best of luck.  You have your work cut-out for you.

[Jeff Highland]

I'd be leaving the neck in place, It will help give leverage to realign the crack plus heat to remove the fretboard may damage the plastic binding and pearliod inlays.

I'd try clamping it down as is  with a caul with the pickguard in place, dampening the wood underneath is likely to make it curl up more.

 

[Jeff Perkins]

I took the pickguard off and it solved the problem. Thanks for all of your help!

[Kerry Krishna]

This pictures reminded me of the FRETS repair photoessay of the car heated guitar, were crack appeared on both sides of the neck and had to be fixed. From close ups of the top it looks like there is quite a bit (?) of old glue in there and that it has been so long cracked that the wood inside the crack has oxidized and changed colour. I hope you can post pictures when it is finished? We would love to see them,I'm sure!

[Jeff Perkins]

Ok, here are some new pics with the pickguard off. As you can see in one of the pics, I'm pushing down on that bit that's warped and it now sits flush with some pressure....so it's now more easily fixable. I did get a little run out, but that was to be expected.