Bridge creep

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Drommy
Gidgee
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Location: Mackay

Bridge creep

Post by Drommy » Fri Oct 28, 2011 12:32 pm

Hi everone,

long time lurker and fan of the forum. Im living in the Airlie beach area (QLD) and Ive just finish my first guitar build O.M style using.
QLD maple back & sides
Bunya pine top
Gidee fret boad & bridge.
Now the guitar has been strung up for about a month and the bridge has started to creep 1mm right across, I used Titebond as the glue was this my mistake? If so can someone put me onto a better adhesive for bridge work and maybe some preping tips it would be greatly appreciated.
Cheers .

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Allen
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Re: Bridge creep

Post by Allen » Fri Oct 28, 2011 1:13 pm

Lot's of bridges glued on with Titebond and without issue, but it wouldn't be my choice. My choice is hot hide glue.

That's a lot of creep in a short amount of time so there must be some issues with the glue, prep, procedure or environment.

First suspect is If the instrument was exposed to enough heat while under tension the glue can soften enough to let it slip.

The glue bottle will have a date stamp on it somewhere and you can check how old it is by that, but a quick test is if it still smells somewhat sweet, then it's probably still good for instruments. If it has a sour smell, save it for other non luthier tasks.

As for prep, good fitting surfaces. Clean and freshly scraped.

Appropriate clamping cauls and pressure. That's about it.
Allen R. McFarlen
https://www.brguitars.com
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Cairns, Australia

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woodrat
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Re: Bridge creep

Post by woodrat » Sat Oct 29, 2011 7:18 am

Hi Drommy, I ,like Allen, use HHG to glue my bridges on. I have been using it now for the last 1/2 dozen of so instruments. I like it in this situation because it is glass hard when it dries and it wont creep. I did have a couple of failures with it on the first couple of instruments (bridge lifting) but that was Operator Error ...I hadn't got used to using it. Now I preheat the parts and get ready to get the glue on quickly and the parts together within seconds of application and the joint clamped another couple of seconds after that and dont worry about mess be liberal with the glue and work fast. Clean up is easy with HHG, just warm water after the joint is safely closed and going off nicely and you have as much time as you want to clean it away :) I also use it for the fingerboard extension so the neck can be taken off easily if a repair is necessary for any reason.
But as Allen said Titebond has been used successfully on thousands of guitars so I find it surprising that yours has crept in such a short time. Has the back of the bridge lifted at all?

Cheers

John
"It's never too late to be what you might have been " - George Eliot

jeffhigh
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Re: Bridge creep

Post by jeffhigh » Sat Oct 29, 2011 10:10 am

Is it a pinned bridge or pinless?

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Kim
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Re: Bridge creep

Post by Kim » Sat Oct 29, 2011 10:16 am

Hi Drommy,

I prefer hide glue also but you should not be having this problem with titebond.. Must ask, has the guitar been exposed to high temperatures, like those you would find in a parked car?? If so that would explain the creep, white and yellow glues soften at quite low extremes. In fact under tension these glues can let go altogether at just 60c (140f), so bridge creep is quite likely under string tension in a hot car. I don't know the maths but in the first 15 minutes you can add 20 to 30 degree C to the ambiance to the inside of a car parked in the sun. So if it's a nice mild central QLD day of around 30c, in 15 to 20 minutes you have reached 60c inside your car....lethal not just to kids and pets but to guitars also.

Cheers

Kim

Bruce McC
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Re: Bridge creep

Post by Bruce McC » Sat Oct 29, 2011 11:06 am

Re the bridge creep, I was wondering what resistance if any the bridge pins would
present to stop forward creep? If the bridge has moved forward by 1mm what has
this done to the pin holes in the soundboard and bridge plate?
Bruce Mc.

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Trevor Gore
Blackwood
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Re: Bridge creep

Post by Trevor Gore » Sat Oct 29, 2011 11:11 am

I've heard of Far North makers having trouble with Titebond, though I don't know any specifics. It's probably to do with heat and damp (humidity). So one story went, the fix was to use LMII white glue, which holds its strength higher up the heat/humidity curve, with the down side, of course, that it's harder to take apart, should you ever want to do so. Some of the trick might be in actually letting the glue dry really hard (i.e. put the bridge on and let it dry for at least 24 hr under humidity control) before you load it. LMII glue is the same to use as Titebond. If I heat bend bindings with purflings glued with Titebond the purflings tend to fall off, whereas if I use LMII glue they don't.

Drommy
Gidgee
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Joined: Thu Jul 16, 2009 11:37 am
Location: Mackay

Re: Bridge creep

Post by Drommy » Sat Oct 29, 2011 1:12 pm

Thank for all the reply's.

Too answer some questions.

No the guitar has'nt been exposed to any extreme heat ,just normal in door central QLD temps and humidity.

Trevtheshed, I picked a cooler day to glue up, Humidity can be higher on cool day's ? so i've been told which may have contributed, and clamped over night.

afshar,the bridge has pulled up from the back about a 1mm I dont think this should affect to much as I've backed off the tension.

Allen/kim, Thanks for the tips I've read up on hide glue in the passed and need to experiment in the future.

The only contributing factor that I can think of, are not cleaning up the bridge area after removing the masking tape when i did my finish? ( french polish) or more glue next time.Thank again everyone.

Cheers

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Allen
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Re: Bridge creep

Post by Allen » Sat Oct 29, 2011 3:47 pm

If you want a sample of hide glue to give a try just let me know and I can put some in the post for you. It's dead easy to use and produces a great result.
Allen R. McFarlen
https://www.brguitars.com
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Cairns, Australia

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