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It's really frustrating when the brace slides around as I glue it. No matter what kind of clamp I use (Stewmac Mini cam clamp, C clamp, spring clamps) the brace always wants to slide around a little. Does the brace have to be on like to .001 inch or can it be off by a little bit? The thing that sucks about hide glue is that there are only about 15 seconds before it gels and by that time any correction will be too late.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Actually, that's really the beauty of hide glue. Get the brace set in place (within 1/64-1/32" is fine) hold it for about 5-10 secs, the glue grabs enough to hold it in place than grab the clamps and clamp it down. It gels but is not hard of course and you can clamp down the brace.

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

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Another alternative is liquid fish glue, which is so tacky that braces which are glued with it won't slide around on you. It's open time is very generous, unfortunately so is the cure time (about 12 hours). It is otherwise similar to hide glue.

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Rian Gitar og Mandolin

Thanks, also on the back I just finished bracing, it curled slightly backward where there's a concave radius that is 90 degree to the braces when I laid a straight edge on the side without braces. I suspect it's from the moisture of the glue and stuff. I can straighten it out if I put forces on it (like when glued to the side) but how much movement is acceptable with guitar wood? I took the back and put it under weight to hopefully help it bend back to a flat.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

When gluing the X-brace with HHG, I also heat the top, the braces also, and I do one leg of the X-brace at a time. Much easier for me this way.

It's really important to put on the notch-up brace first.

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formerly known around here as burbank
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http://www.patfosterguitars.com

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http://www.dickeyguitars.com

Another recommendation for HHG to ease brace displacement. I also glue one limb of the X at a time. If you dry clamp with the X assembled and mark carefully it's worked fine. I've been laying my heating blanket out on the workbench and setting it to around 150 and just laying the braces on it while I get things ready. I've had plenty of time to get things set. The bridge plate was always my biggest problem with sliding before.
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

One thing that's extremely important is NOT to use to much glue!!
You do NOT need to spread it on both gluing surfaces-you do NOT need a thick layer either.
Ouze out(large amounts) is a warning of to much glue!!!

Try some experiments with waste wood-gluing up pieces and get a feel for how much glue you need-if a light coat tacks and the pieces do NOT move -you got it right!

Mike

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Mike Collins

Unless your religion requires you to use hide glue , you will probably find it a lot easier to use LMI's white instrument makers glue.

If you clamp hide glue after it has gelled, you won't get the best bond, because there is a limit to how much the gel can be compressed. That's partly why they give hide glue a number for gel strength.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Now have you ever thought of taking that partially gelled squeze out and putting it back in the jar or bottle? Would that be a bad thing?

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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

Here's an update:

I managed to clear out my "go bar deck" (the laser printer is useless now) and I made some go bar with some hardwood trim they use on walls. So now I have 2 tone bars glued on at the same time.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

That's the idea. One question though? Are your braces arched on the bottom? You are clamping on a flat surface underneath them.

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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

These are pre-shaped and arched stewmac braces... so yes they are arched in the bottom. I copied and cut the arch onto a piece of plywood so in the future I can buy pre-shaped braces from LMI and arch them myself.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

So your clamping the arched braces onto a flat surface? What do you think that will do to the arch in the brace?

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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

The instructions that came with the braces and stewmac kit instructions says to clamp it to a flat surface and when released the top will conform to the arch. So far it has.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Yes, it will do that but there will also be some stress on the glue joint as the brace was forced flat when glued now it pulls up on the top plate and the glue joint is stressed because of this. It's probably not much but it is there. It also won't be as arched as it was before gluing it to the plate. Depending on the strength of the glue joint, over time that stress may cause the joint to separate. This is why we use a radius dish to glue the braces on. That way there is no stress in the brace, just a bit of stress in the top or back plate.

_________________
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

Rahimiiii,
I use clamped guide blocks as described above. As a rookie, I've found this to be very helpful in that it helps keep the braces in their proper alignment while I focus my attention on getting even clamping pressure.

Radius dishes are optimal, but there are other cheap and easy ways of getting the radius into your top and back plates before gluing the braces to them as well. One method I have used is to stack 3"x5" note cards in a staggered progression to match the arch of the braces. It's hard to visualize when written, but here's a link to text and pictures that explain this technique pretty clearly:

http://www.kennethmichaelguitars.com/contourtool.html

It's not pretty, but can get the job done.

Best,
George :-)

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George :-)

With all the respect for you that I can muster, Rod, I have to disagree. The amount of stress put on the top of a typical flattop guitar to make it conform to 25 or 30 ft radiused braces is negligible compared to the stress from the string pull after the guitar is strung up. I don't think clamping flat is a problem, even long term.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

Lots of strong points and techniques regarding bracing placement and proper gluing, sliding around etc.
I agree with Howard in the use hhg, also the tension and pressure exerted by stringing to pitch far out way the slight negative stresses created by clamping flat otherwise radiused braces.
One thing I find helpful in setting a brace and holding it still for clamping is to apply small drop of CA in one or two spots on the brace, just a tiny drop held firmly for a couple seconds usually will lock the brace in place long enough to get the clamps set.

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Nehemiah Covey
www.coveysacoustics.com

I'll try that next time, thanks for the advise. I used to do that in my rocket building days (gluing fins to a body without any clamps) but I was concerned about CA glue ruining the bond or something...

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I'm new to gluing up braces with a go bar deck and HG but I put my go bars on about every inch or so. I just glued on the X brace the other day and put the intersection go bar on first and then some where near the center of the rays and then the ends and then filled the gaps. I used a 4 oz. squeeze bottle that floats in my Rival Hot Pot Express (much cheaper then a glue pot, $20 or less I think) to apply the glue down the brace and placed it. Pretty much, well just like John Mayes does in his video. It's pretty fast and faster then messing with a brush. For what it's worth.