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OK, here is a question that I fear I know the answer to, but I'll ask anyway.

I have a bridge on a recently completed OM that has popped loose at the tail side, bass side wing corner. The bridge seems fine under tension, FOR NOW ... I'm toying with the idea of shooting a little hide glue under the corner with a hypodermic and reclamping, but ... also thinking that the joint is crap and the bridge should come off, get cleaned up and reglued. The existing joint is fish glue.

What y'all think? Bridge off? Quick fix-up instead?

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Jim Kirby
kirby@udel.edu

I'm a beginner, but I know what the big guys will tell you.  So do you! 

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Waddy

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Sound Clips of most of my guitars

Hi Jim - I'm just a beginner too but if it were me I would remove the bridge.  Explore why this happened and here are some possibilities:

1)  Bad glue joint.

2)  Surfaces not prepared properly prior to gluing.

3)  Bridge not radiused to the top or the top radius changed do to RH and the joint was not good in the first place.

4)  And this one I heard happened to some guy named Hesh1956 - the clamps when gluing were tilted forward and the back of the glue joint had no real clamping pressure.

Any way once I determined and eliminated the cause, cleaned up both mating surfaces  I would glue and reclamp.

If you search the archive under "bridge removal" I am told that there is "one method" for removing your bridge that might be helpful to you.

Good luck.

I'm with Hesh on this one....maybe the bottom of the bridge doesn't match the radius of the top.

YOu better remove it before it comes undone and tears out the top while poping off....

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

How long did you leave the clamps on. I don't use fish glue but what I've read about it you need to keep the clamps on for longer than other glues. Maybe you did this right the first time though.

Yup, I agree with the other guys. Remove the bridge, prep both surfaces properly and re-glue.

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Jim don't put the hide glue in and re-clamp. It most likely won't be a wood to wood joint and it would most likely fail again.

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My Facebook Guitar Page

"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

Ditto...the peace of mind is worth the extra time and effort to remove and re-glue (AFTER prepping the gluing surfaces again)!

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http://www.presnallguitars.com

I think that Fish Goo requires 24 hours clamping time and David Collins would be the resident expert to ask about Fish Glue.

OK, OK, the reading in the 8-ball is clear!   

I have my 11 buck Tower Hobby heating iron, so it's time to put it to use. Fish goo doesn't give up easily, but at least I have a little bit of a corner to get some water under.

I had the fish goo clamped long enough, certainly. I suspect it was probably more like uneven clamping load, like Hesh's case. I was using the LMI clampless caul, and wasn't real happy with how it sat on the curved top of my bridge.

Hesh, you may be an amateur but you are about 10 guitars ahead of me. Thanks for the help and pointing to the archive discussion.

Jim

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Jim Kirby
kirby@udel.edu

Making sure it's a fresh, solid, well fitted wood to wood joint is about the
most important part, with good even clamping pressure being a close
second. And yes, I would certainly remove and reglue, like has already
been decided.

Fish glue is pretty heat resistant, so when removing a bridge I like to
dampen the bridge while heating it. I prefer heat lamps over heating irons
for bridges, so I can just repeatedly moisten the bridge with wet rag,
effectively working a bit of steam in to the bridge joint as I'm heating it. I
do the same thing with hide glue joints.

I've only had one fish glue bridge joint fail on me, and that was a personal
beater guitar that hastily fit and clamped, then tried stringing up about
two hours after clamping. It peeled loose almost immediately at the back
edge and wings, which hide glue wouldn't have done. For all practical
purposes, fish glue is just as good as hide for bridges in my experience if
they are well fit and properly clamped. That said, I've since switched back
to hide glue on bridges, because a bridge glue up just doesn't need much
open time, and the faster I can move to the next step or free up a set of
clamps, the better.

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Eschew obfuscation, espouse elucidation.

Thanks Dave - yes, fish glue really ties up the equipment with it's long clamping times. I can really see how that becomes an issue for someone working at this for a living - it has to at least double the overall time to assemble a guitar. For me, I'm lucky to be able to free up the time where I need the clamps or guitar for the next step, so it's a non-issue. (Bridge clamped for a week? No problem!)

I'm more worried at the moment about the heat resistance. I had to take apart another fish glue joint a few months back, and it wasn't fun. But I understand that moisture is the key.

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Jim Kirby
kirby@udel.edu

[QUOTE=David Collins] Fish glue is pretty heat resistant, so when removing a bridge I like to
dampen the bridge while heating it. I prefer heat lamps over heating irons for bridges, so I can just repeatedly moisten the bridge with wet rag,
effectively working a bit of steam in to the bridge joint as I'm heating it. I do the same thing with hide glue joints.[/QUOTE]

David, you're a busy guy and this probably isn't possible, but could you either explain (or maybe shoot a photo) of "how" you use heat lamps to get the bridge hot enough to create steam with the water, without doing some degree of damage to the surrounding top/finish? I don't doubt you, I've just never seen it. Thanks.

Bill

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Eagles may soar, but weasels don't get sucked into jet engines.

Cardboard, tin foil, HVAC metal tape, and a 250w heat lamp. I prefer the
heat lamp over hard electrical heaters because I feel it easier to control.
The heat is relatively evenly distributed through any dark surface, and you
don't suffer hot or cold spots from uneven contact with a metal heater. I
cover a cardboard mask with aluminum foil, and tape over the bridge
about 1/8" in from the edge with metal tape. If you want to keep heat
away from anything like inlays you can just cover them and their
surrounding area with reflective tape.

As to the steam, I'm not really generating a huge amount of real steam. I
will generally just wet the surface with a wet rag every 30 seconds during
the 3 minutes or so of heating. Most of the water steams off in to the air,
but enough seems to work it's way through to help at least a bit. Without
moisture, fish glue will heat much like hide glue, seeming to crystalize a
crack apart more than softening like PVAs. With this method it does seem
to soften a bit more than with dry heat.

_________________
Eschew obfuscation, espouse elucidation.

_________________
Eschew obfuscation, espouse elucidation.

Thanks greatly David...I haven't seen that before. That's a neat way of doing it.

Bill

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Eagles may soar, but weasels don't get sucked into jet engines.

[QUOTE=Bill Greene]Thanks greatly David...I haven't seen that before. That's a neat way of doing it.



Bill

[/QUOTE]

I agree Bill buddy - and no tan lines either........

Wow David, that's cool! (Well no, but you know what I mean! )...thanks for sharing!

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http://www.presnallguitars.com

Thanks for all the advice. I would have liked to get to the job this weekend, but I was more preoccupied getting the bridge on for the first time on this one ...



Still have a lot of cosmetic work and fp'ing to go yet.

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Jim Kirby
kirby@udel.edu