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What would you guys recommend as the best way to repair this cracked headstock? The crack is only partially through and it has no affect on the trussrod function. It's from a 1965 Gibson EB-2 that was destined for the garbage. Other than the crack it is in very good condition. I'm thinking it might be possible to resurrect this old bass. Any repair gurus out there?



Thanks!

John

seems you have two p;osts on this subject john. without seeing whow the crack separates i think rick's advice in the other thread is on track.

It looks like a straight glue and clamp job from here. How fresh and intact
the surfaces are would help me decide the glue (fish glue if fresh and clean,
perhaps epoxy if more heavily weathered or missing wood). No need for any
spline/overlay system judging from the photo.

_________________
Eschew obfuscation, espouse elucidation.

Seeing the photo, I agree with David. I was thinking major Gibsonitis, not minor.   You could inject a bit of very hot water, let the water drain out well, and then wick in fish or hide glue. You'll be amazed at how far in the glue gets when the wood is hot and damp. Clamp it up overnight, clean it up and then you could do a bit of finish touchup. It'll wind up practically invisible and quite strong. Worst case you then can do an overlay if need be. Do the least amount possible that actually gets the job done.

Trash can, eh?   That's almost a collectible bass at this point.

rick, i've not heard of your hot water technique before. always nice to pick up something new, and you've given me something today. will be looking forward to something appropriate to try it on.

i was going to reccomend alittle steam, sweet gibson, i have 4 and a 59 reissue, that is a nice addition to anyone's collection!!

 

[QUOTE=Rick Turner] You could inject a bit of very hot water, let the water drain out well, and then wick in fish or hide glue. [/QUOTE]

I've never heard of that before but I'll definitely give it a try. It's a very clean crack that still fits together very nice. So fish glue is the recommended glue? I've never used it but will go pick some up for this job.

Thanks for the info fellas!

John

FG was a joy to use on my 1st repair of a crack. Just make sure you keep it clamped for 24 hrs.

It's good stuff and thanks to David Collins, I learned a grreat deal about cracks and acquired some FG in the meantime. I didn't know about Rick's hot water trick, but I made a pump setup that included a fine gauge butterfly needle to get the glue into tight areas.

See below:

_________________
JJ
Napa, CA
http://www.DonohueGuitars.com

Some caution about fish glue here:

http://www.player-care.com/hide_q-a.html


"Q: I was told that fish glue is just as good as hot hide glue, just as strong, and much easier to apply. What do you think about doing a player with it?

A: Fish glue is a "specialty glue" only. It is not designed to glue player actions together. It is mainly used for emulsions, but the pipe organ industry uses it to get an instant grip between leather and leather, or leather and cloth. It allows soft lambskin to be contoured around corners because of its cold tack properties. On the other hand, fish glue is very hygroscopic (meaning that it draws moisture from the air). Long-term humidity alone can disassemble parts put together with fish glue, whereas hot hide glue, once fully dry, can withstand about any amount of humidity without weakening, and over 400 degrees Fahrenheit without softening."

If you Google "fish glue" the low moisture resistance thing keeps coming up. The only reference I've seen to higher moisture resistance is in a monograph on Mongolian archery bows where the fish glue preferred is made only from the air bladders of sturgeons and is moisture resistant.   All the stuff that seems to be available is quite hygroscopic...fine at low humidity, but questionable at higher humiditiy.

Based on that research, I wouldn't use the stuff on guitars. Sure, it's easier to use than HHG, but it's not better.

The fish glue/moisture resistance concern comes up quite often, but all
references to the problem always seem to lead back to the same
reference mentioned by Rick. Unfortunately I have never been able to
figure out where the piano technician who wrote that article based his
information.

Historically I am sure that what was termed "fish glue" varied quite widely,
from isinglass to various cold water fish skins. The above author may
have been working with (or reciting problems he's heard of others having)
with a very different formulation from what is available today.

In any case, I've used High Tack Fish Glue from Norland Products and
have never had any issues with humidity resistance. I know of one luthier
(I believe in Taiwan) who has had issues, but lives in a 90%+ humidity
environment year round. In this case no natural adhesive including hide
glue would stand up for too long. I also am unsure what brand or
distributor he used, which can certainly matter. My fish glue does have a
shelf life of perhaps a year and a half to two years, even when
refrigerated, so I never buy from a reseller who may have an inventory
sitting on a room temperature shelf for two years. I order once a year
straight from the manufacturer and have never had any problems. I've
even accidentally run a few cutoffs left in my pocket through the washer
and dryer and they've come out intact.

Still, it is somewhat hygroscopic like Rick said (as is hide glue) and I
wouldn't build boats with it. At 80%-90%+ humidity for extended times it
may very well give, but so do the hide glue joints that I see come from
Michigan basement storage. They may differ at what point they start to
give, which although I have not quantified seem to be relatively close.
Heat resistance is excellent for both Norland Fish Glue and hide glue.
Again, there may be more real basis for the concerns with other fish
glues, but I've not seen any with the Norland High Tack.

The biggest drawback in my opinion is it's very long clamping and curing
time. I certainly wouldn't be using it for production if I had to leave things
clamped for hours to overnight. In repair however, it's long working time
is wonderful. I keep my syringe filled all the time. The butterfly needle in
the pic is mainly for hard to reach brace reglues. For a crack like that I
would either use a straight needle, or just work it in by hand.

[IMG]../forum/useruploads/DavidCollins/2007-07-31_144454_2.jpg[/
IMG]

Unless you want to buy a few gallons straight from Norland however, Fish
glue probably wouldn't be worth going after. I would do as Rick
recommended, as if you don't already have hide glue in the shop it is
cheap, easy to find, and very reliable. I didn't even mean to mention fish
glue in my post above because the mention of it usually diverts the
discussion from the main topic, but I slipped.

_________________
Eschew obfuscation, espouse elucidation.

Good info fellas! Man JJ, your glue dispenser looks better than a lot of my jigs. So does the wicking of the glue by using water work equally well for hide and fish glue? I'd like to try fish glue but not unless I can find some that is dated. I guess this will be a good excuse to get a glue pot and start using HHG.

John

I've never tried wicking with fish glue because it has such a long working
time that you have ample time to work it in to deep cracks. My pic didn't
work above, but here's my glue injector.



With use of a flexible arm and an alligator clip it's great for interior repairs
like loose braces. For a repair like your headstock it's not really necessary.

I would say it's time to get set up for hide glue. Even if it won't be your main
glue, it's something everyone should be familiar with and have on hand.
There's a bit of a learning curve, but for many who haven't used it before it's
often more intimidating than it is difficult.

_________________
Eschew obfuscation, espouse elucidation.

Wow David,

What an awesome look'in injector, I'm going to make one just to chase my kids around with when they misbehave.

Cheers

Kim

BTW, you could drop that syringe with the tubing into a glue pot full of water or a crock pot and keep the glue at just the right temperature, then pop it into the injector holder and you're off to the races.   The glue in the tubing is going to gel faster than in the syringe, but you can just pop it back in the hot water to keep it nice an liquid.

Re. the fish glue...everything I see indicates that it's very hygroscopic.   I can't see the advantage to using it other than it doesn't need to be kept hot. It's not stronger than hot hide glue, and I wouldn't want to take the chance that a guitar made or repaired with it might experience high humidity and start to fall apart.   

What are the advantages?

If I were going to use fish glue for this repair ( I would probably opt for hot hide glue) I would the type recommended to me by Richard and Marshall Brune...Isinglass. Dick Fine Tools sells it. Part #450142/58/59. The glue is made by "processing and drying the inner membrane of the air bladder of a Beluga...a sturgeon". Dick claims itis the strongest of the animal glues. "If kept in a dry environment, the bonds are also highly resistant to the effectsof age."

It is very expensive. I used it on an older Martin that was pretty beat but the owner insisted on taking it to the outdoor bluefgrass festivals every weekend. here in Fla that means very high hummidity. So far it is the only thing that didn't fail...but I caution...this is SO FAR...who knows what will happen next weekend.

By the way, I have repaired many a cracked headstock with cracks similar to that shown in the pic above. I always use HHG. Never had one come back.

_________________
Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

From everything I've read, the sturgeon bladder fish glue is indeed the most moisture resistant of any of them. Apparently the Mongols used it in making their recurve archery bows with which they were deadly out to 350 meters...