Fixing a Partially Cracked Headstock

[Cagey]

The truss rod doesn't turn; tension is applied by tightening/loosening a nut at either the headstock or heel so the rod doesn't move much, if at all.

 

[davegardner0]

Yeah but doesn't this end of the rod move along the length of the neck some as the truss rod nut is tightened/loosened? (if it's a single action rod, which I'm assuming it is based on the adjusting nut)

 

[Cagey]

There's a very small amount of longitudinal movement as the neck curves, but that's it. Don't get me wrong; you don't want the rod seized in its channel. But, I'm not sure a bit of fish glue is going to do that. Lotta pressure in there, and it's a wood/metal facing, which doesn't glue well. If you'd have poured epoxy in there, then I might be concerned.

 

[rob91bob]

Just a thought for future reference. I can't remember who it was but I saw a repair video on YouTube where a guy was working on a crack and he applied the glue while holding the crack open as much as possible then used compressed air to gently force the glue into the crack. It seemed like it worked really well.

 

[davegardner0]

Well after 36 hours of clamping I checked my joint. It looked good (the crack was closed nicely) but when I stressed it with a medium/high amount of force it failed and now I'm back to square one.  ??? :doh:

My guess is that I thinned the glue too much and therefore didn't actually have enough glue inside the joint. Full strength fish glue will still go through the syringe (slowly) so I'm going to try that next. But first I have some scrap pieces glued and clamped, to test my fish glue and make sure it didn't go bad.


Oh but the truss rod works!

 

[Cagey]

Well, that sucks. Hopefully, the next go-round will be the charm.

 

[AirCap]

Sorry to hear that. Well - clean out the old best you can, and try again. You could wash it out, but you have to wait a week for the wood to dry, and even then.... Chalk it up to experience, and better results next time.

 

[stratamania]

A pity it did not work but next time why not just use Titebond and doubleAs idea.  It would be much stronger in the end.

 

[davegardner0]

A pity it did not work but next time why not just use Titebond and doubleAs idea.  It would be much stronger in the end.

As to why I didn't break the headstock off completely there's a simple answer...the owner of the guitar vetoed it! So that was that.  :icon_scratch:
Plus I was able to get glue into the joint as-is, and right now the crack in the finish doesn't extend to where your hand goes while playing. If I broke the headstock off it definitely would have a crack all the way around the back of the neck.

As to why I didn't use titebond, first of all I don't know how old the crack is so it could have some foreign material in there. For titebond you need a clean bare-wood joint but fish glue sticks to everything. Second, I like fish glue because it can be disassembled and repaired/reworked if needed without needing to clean the old glue out of the joint. That'll definitely be helpful here as now I need to glue it again and have glue residue in the joint already. If I'd used titebond I would have to (somehow) clean all of the old glue out of the joint before regluing.

Not saying I have all the answers, but that's the logic of why I went the direction I did.

Right now I'm in the middle of trying to verify that my fish glue didn't spoil before I make a 2nd attempt at gluing the crack. I'm 90% sure it failed because I dilluted the glue and ended up with a starved joint, but I need to be certain that my glue didn't spoil.

 

[stratamania]

Understood. Wish you success this time round.

 

[dmraco]

I recently corrected a similar problem on an Ibanez.  I used a razor blade.   

I coated the blade with tight bond, GENTLY applied pressure to separate the crack just a bit and inserted the blade in the gap.  I then released the pressure and pulled out the blade.  The blade came out clean for the most part leaving the glue in the neck.  I did this several times to make sure the entire area was coated. 

Clamp and wipe of excess glue.  Still holding for the owner today!!!

Good luck

 

[Rick]

Fish glue?  What I've seen at repair shops is either hide glue or titebond.  Given the damage I wouldn't worry about making it worse.  I'd jam in as much hide glue or titebond as I could. Clamp it.  If it fails get a new neck. 

 

[davegardner0]

Well the 2nd gluing with fish glue seems to have been totally successful. It's really solid now and the truss rod still works too. I suspect the glue was just thinned too much the first time. Even though the full strength fish glue is a LOT thicker and more tacky I was able to force it through the syringe and into the joint just like the first time.

So far, so good!

 

[AirCap]

Good to know.