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Hi all.

I just glued a belly style bridge onto a dread body last night using hide glue. I thought all was well until I checked it this morning and found that the 2 corners of the wings closest to the lower bout had small gaps under them. On one, I could slide a piece of paper 1/16" under it, on the other, it's closer to 1/8". Everywhere else is seated perfectly as far as I can tell.

I guess I should have been more diligent in sanding the bridge to fit the top perfectly. I did sand the bottom against the top, but it wasn't quite there.

SO....

Do I take the bridge off and start over, or, since I used hide glue, can I do something like work a little more under the corners, re-clamp, and introduce some heat to reactivate the glue under the wings?

I'd really appreciate some guidance here.

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-Clint Beacock

I'm thinking you will need to take it off.

Did you arch the bottom or flatten it to the contour of the guitar?

Also, did you clamp the wings as well as the main body of the bridge when gluing up?

We've all experienced ill-fitted or ill-glued bridges.

You can sand the contour onto the bridge prior to lacquer removal by taping sandpaper to the guitar face.

Hide glue is my choice here.

It seems that gluing the wings after the fact, never works well. We've all tried that too. Rarely does it stay down, but you could "try it".

Again, four contact points are good doing a steel string. I use two Klemmsia Clamps in the middle, then two long arm steel C-clamps for the wings using little mahogany clamping blocks to protect the bridge. In other words don't clamp the c clamp directly on the bridge.

Good luck. Pictures are always helpful. bd

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http://www.dickeyguitars.com

At last a question that I can answer!
Take that baby back off and refine the fit. DAMHIKT.
Heat the bridge until it comes off easily, clean it up, refit, and you`re back in the game.
Coe Franklin

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

You could either-

-Take it off and make it perfect. Bridge removal can be a bit tricky and there is always the possibility of damaging something.

-Leave it as is, knowing that you have a bridge with a head start on lifting, that will need to be reglued at some point. All bridges will need to be reglued during the course of the guitars life, yours may just need it a little bit sooner, or you might get lucky.

No one can really give perfect advice without seeing it, but if it bugs you enough to ask about it, it may be time to get out your pallete knife.

Those south corners are easy to neglect, as they are the last part to be sanded, and by then you are sick to death of sanding and start to think "oh yeah, the clamp will pull that down, its soo close", unfortunately, it wont.

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Jordan Aceto
Ithaca, NY

It sounds like the moisture in the glue made the corners curl up. When gluing relatively thin stock with TB or HHG I always wet the other side.
An easy way to remove the bridge is to rout it out almost flush (with 2 rails fastened to the base), and finish with a sharp chisel.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

I think Laurent may well be right about the cause. One idea is to wet the top of the wings now - maybe try very hot water, even - and see if that makes the corners go down. It might take several wettings over the course of an hour or so. If the corners do go down, then you could try working a bit more HHG under them and reclamping. When everything dries, you just might be all set.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Thanks for the replies!

I guess I'm gonna bite the bullet and take the bridge off, properly surface the bottom and reglue.

Laurent, I'd never heard of wetting the other side of the bridge, but I'll give that a try when I reglue.

Edit I was typing my reply as you submitted your suggestion, Todd. It's one more option to think of. Have you ever tried this? The thought of getting the tips down without taking the bridge off appeals to me, as it's a very small section. But I do want to make sure I'm not gonna have lifting problems a few years down the road.

Again, thanks to all of you.

_________________
-Clint Beacock

I haven't tried it, Clint, but it seems to me you haven't got anything to lose by trying it, unless you're pretty sure the cause of the problem was improperly contouring the bottom of the bridge in the first place.

Bear this is mind: lots of people don't even glue their bridges down all the way out to the edge (or the glue around the edge is very weakly bonded to the finish rather than the spruce). If you don't have finish going under the edges of your bridge, then your glue joint already has an advantage that many don't. Plus, the main peeling force on your belly bridge is along the back edge of the belly, not at the corners. So, I wouldn't be too paranoid about the quality of the joint if it's good everywhere but a tiny bit of the corners.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

I've heard that all guitars would eventually need a neck reset but I never heard that all bridges will need to be reglued again. I'd be interested in hearing more evidence of this. TIA.

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

Well, i dont have any evidence, but it is something i see alot and consider to be routine maintenance, like the brakes on your car.

Working in a brisk repair shop, you see several bridge reglues a week. Crummy guitars, nice guitars, really nice guitars, they all come in for bridge reglues eventually. A well glued bridge may last many years, but its time will almost inevitably come.

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Jordan Aceto
Ithaca, NY

Thanks again for your reply, Todd.

I thought as well about how some leave a little finish unstripped around the entire bridge. It is a very small bit that's lifted, so the first thing I will try is to get it glued down. I am confident that the rest of the bridge has made a good connection.

It's possible that moisture was a factor, but I'm sure that I should have spent more time sanding against the top. I was rushed to get it down because I had other things I had to take care of (5 month old).

I think my clamping was a factor as well, as my clamps were -barely- able to reach the wings. I had a pretty good caul setup, but the throat length of my clamps being just a 1/4" from ideal was making it hard to get the outer clamps to keep from wanting to pull forward instead of just applying downward pressure.

I have a vaccuum kit I'll be putting together soon, so I think this will be the last bridge I'll have to use clamps on (it's only my second bridge).

I really appreciate all your help. This forum is a great thing to have access to.

_________________
-Clint Beacock

Do you know about putting pencil lines on the bottom of the bridge while sanding? This helps a lot to see exactly where the sandpaper is making full contact, so you know when to stop. I usually end up re-penciling a few times during the sanding process. When you've re-penciled and then a few seconds of light sanding removes all the pencil lines, you know you've got a good fit. This is a trick I use all the time for all kinds of sanding operations. I couldn't live without it.

Another thing is, it's easy to unwittingly rock the bridge slightly as you sand back and forth, or to flex the wings downward a bit with hand pressure as you sand, so that you actually sand the ends and/or edges more than the middle and don't end up with an accurate fit. One way to avoid that is to sand on a domed sanding board that has a slightly tighter radius than the top itself. I actually don't usually sand the bridge right on the top (for several reasons). I measure the radius of the top with radius gauges I got from Tracy at Luthier Suppliers, then use a domed sanding board (I've gotten some from Tracy and made some myself) that's either the same radius as the top or a little tighter. I don't mind if the bottom of the bridge comes out with a slightly tighter radius than the top itself, because the bridge and the top will have enough flex that, with good clamping, the middle will make solid contact and glue down well, and the edges will surely be really tight. I'd much rather have that situation than the opposite, where the edges may be predisposed to peel up.

Another tangentially related situation with radii is how one goes about arriving at the radius one wants in one's top. I've found that if I sand a 28' radius in my braces and glue them on in a 28' dish, the top will not end up with a 28' radius, because the top has it's own stiffness that will pull it back into a flatter dome. So, what I'm trying on a guitar I'm currently building is sanding my braces to a 25' radius and gluing them to the top in a 25' dish. Then, I'll sand the rim in a 28' dish, and glue the top on in a 28' dish (the box is top-side-down in the dish when I glue the top on, with go bars around the edge of the back). The results remain to be seen, but I'm fairly confident I'll end up with something closer to the intended 28' radius.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Yeah, Todd, I did do the pencil thing a few times, but I got to the point where I figured I was 'close enough' i.e. I was rushing. In the future, I'm going to be more diligent at this step and bring the bridge to a slightly tighter radius than the top.

I'm gonna make up some radius blocks and gauges for myself. I'm a machinist by trade and have access anytime to the CNC's so I'll just need to find the time to do it.

I had wanted to tool up properly before starting this guitar, but a friend wanted me to put an instrument together for his son. I declined numerous times, but gave in. I really don't have the time I need to do it right now, and I wish I hadn't committed myself (even though I told him I couldn't guarantee any sort of completion date and only had 1 instrument under my belt).

I have enjoyed the process so far, though, and if I hadn't agreed to it, I wouldn't be building at all. The guitar is shaping up to be better than my first in all respects but this one, and I think it will sound nice, but of course I can't be sure of that yet.

But my focus this year is going to be to really tool up. I won't start another till I have every jig I think I could want.

Wow, way off topic here! Thanks a lot for your help here Todd. It's not the first time you've been a help to me and I do really appreciate it!

_________________
-Clint Beacock

Having to remove and reglue a bridge that is fitted and glued properly in the first place
is a rarity. With almost 500 guitars in the marketplace from my small shop, I've only
had a single bridge....that's one bridge....that has needed to be reglued because it had lifted
That one had lifted after the guitar's owner decided to leave it in the back seat of his car while
he played football for three hours on a July afternoon.

Fit it right and glue it with good quality glue and you'll likely never have to touch it. My oldest
acoustic guitars are in the 20 year old range and none of them have ever had the need for the
bridge to be reglued.

I've removed and replaced bridges on lots of junk guitars that are pumped out of production
houses overseas, a good number from the large production houses here in the States ad only
a very few on guitars from small to medium sized shops where more attention is paid to the
gluing and clamping process...and adequate time is allowed before a load is applied to the joint.

It is, by no means, a common repair or a routine maintenance procedure or consideration. A
well glued bridge can last forever. When you're sanding the bottom of the bridge to fit it to the
top's arch, be sure that you put jacks inside the guitar as well or apply very light pressure to
avoid distorting the top and giving the bridge a false reading of its shape as it's transfered.

I'd suggest that you take it back off and fit it right. Your wings would have to be exceptionally
light for the moisture from the glue to curl them up. You'll be very glad if you just take the time
to get it right now. If you don't, it will bother you every time you look at it and it will be something
that other people will notice when they see the guitar.

Make it something that you're proud of the first time around.

Regards,
Kevin Gallagher/Omega Guitars

I guess I'll have a look at it again tonight. I've been busy these last couple of days so I've only had about 2 minutes total to look at things. It's likely I'll end up taking it off, and if that's the case, do I have to sand into the top a little to get rid of any hide glue that's penetrated, or can I just sand to the top, properly re-sand the bridge, and trust that any residual hide glue will reactivated by the fresh application.

I only ask because I got the impression from our recent hide glue thread that it will reactivate with a little heat, but I may have misunderstood.

Thanks for weighing in with your experience, Kevin.

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-Clint Beacock