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A guitar I made two guitars ago now has a problem, the pinless bridge I installed is lifting at the trailing edge. Um. Looks like I didn't do enough of something right... My question is what's the downside to getting more Titebond into the gap, it was built with Titebond, and clamping it up and see if the re-gluing holds? Worst case, the bridge comes off anyway and gets re-prepped for installation and I've spent little effort on the speculative re-gluing and I've done minimal disassembly and bashing.

And thinking(?) a bit, am I seeing this correctly? Pinless bridges have different forces from string tension playing on them compared to string forces in pinned bridges. A pinless bridge's string forces all pass through the installation glue joint, while a pinned bridge's string forces are directed to the soundboard by the ball ends hooked on the backside of the soundboard, and the bridge ain't doing much.

Thanks, folks.

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Peter Havriluk

No actually the worse case is the bridge comes up anyway, and it will and tears up the top making it more difficult to repair.

There is no short-cut on a lifting bridge to removing it, exploiting the gluing area and cleaning all you can to bare wood and regluing. We exclusively use HHG for bridges and clear finish to about .010 of the perimeter.

We dropped a major manufacture and told them to take a hike we would not do their warranty work anymore because they wanted their warranty repair shops to squirt glue under a lift or lifted wings, clamp the hell out of it and... next.

We told them that it's our name that the client will know when it comes back off so we refused to do it their way. That ended the relationship and I will not say who it way.

Our process is to remove the bridge, expand the wood - to - wood gluing area and reglue with HHG. I fit bridges to be down all the way around with only minimal finger pressure. Of course we clamp, have all clamps in place in about 10 seconds or less.

Peter this is one of yours too. If it was one of mine and I did have a bridge lift on a Heshtone but it was left in a hot car for a week... I would want my A game for bridge reglues and wouldn't be cutting any corners.

PS: I would not use Titebond and would not have used it on a pinless bridge in the first place. It can cold creep and a pinless bridge is in shear which is what Titebond does not do well. HHG and proper methodology is a better choice.

It's possible to have a bit of creep that is not catastrophic - but one never knows. My advice to the client is usually complete removal and reglue - or wait until it comes off and face the consequences then.

Good call on the hide glue.

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"Act your age, not your shoe size" - Prince

Hesh, thanks for your comments. Now I get why I think the bridge had two bolt holes in the trailing edge...

A related question, seeing as I have no HHG capability at present, but I do have a new bottle of 'Old Brown Glue' sitting in the refrigerator, and has been for some months: This stuff any better than Titebond by your lights? And how do I tell if this unused bottle is any good? Testing before use, somehow?

Thanks!

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Peter Havriluk

I've never used it so keep that in mind. But the repair folks that I hang with are HHG fans which I know is not what you need to hear right now.

The value add of HHG to me and many is not only it's non-creeping bond (if not abused in heat) but how hard and crystalline it dries making it presumed to be a great transfer medium for vibration. Vibration is what we seek to preserve on a wooden musical instrument.

So plasticizers and such found in OBG and even methods to extend open time of HHG are not of any interest to me. Countless luthiers for centuries have learned to use HHG within its working parameters. From hot rooms and working in your boxers or commando if the bending iron is off to just doing dry runs and getting faster HHG can be a joy to use. It's very predictable.

So not looking to argue but I will that I'm a HHG purest and instead of trying to make Old Brown Glue work why not see this as an opportunity to learn the art and skills of HHG bridge reglues? There is nothing to it and it's al in the great prep that we do before hand. Once you do you won't want to do bridges any other way. As you can see I'm a HHG/bridge snob now.... but that's because I can't have the hundreds of them we have done coming back to haunt me.

Hesh, you sure you're sure?? Thank you very much. I concur with your suggestion that I have a learning opportunity. Incumbent on me to climb the preparation and learning curves which seem to make the execution anticlimactic. Ten seconds before the clamps are fixed? That's going to take some fancy learning and practice.

Now if somebody could point me to a suitable (aka, cheap) heater I could use to heat that jelly jar of hide glue, I'd be grateful. Heating that jelly jar in hot water on the cookstove is out unless there's no other choice, my knees fuss at repeated ascents and descents up and down the cellar stairs.

Seeing that the bridge will be coming off, I could see if I can also gin up a pinned bridge to replace the pinless one. I found setting up the instrument with a pinless bridge is a PITA.

Thanks, everybody.

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Peter Havriluk

Best bang for buck, in my view, is a beautician’s wax warmer. The 1 litre models I use cost $50 and are fairly stable in terms of holding temp.

Many have also successfully used mini crockpots acquired second hand for a few bucks.

And then there’s the Frank Ford “no-pot” method, which is a great way to go for occasional glue ups:

http://www.frets.com/FretsPages/Luthier/Data/Materials/hideglue.html

Mini-crockpot user here - warms hide glue and lacquer.

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"Act your age, not your shoe size" - Prince

I use a baby bottle warmer (~$20 at the department store) with an adjustment knob. A candy thermometer lets me dial in the temperature. When I do a bridge. I heat it with a heat gun until it’s warm to the touch, put the glue on the bridge, slap the bridge on the guitar (with locating pins), and clamp it. It takes no time at all. I upgraded to a vacuum clamp several years ago. It’s easier and less likely to distort the bridge than multiple cam clamps.

I keep the HHG in small plastic bottles with marbles in the bottom to keep them from floating. In between sessions, I store the bottles in the freezer so I don’t have to make a fresh batch every time. On the days I do gluing, I put the bottle in the warmer when I enter the shop. By the time, I have my joints cut and prepared, the glue is ready for me.

Once you get the HHG down, you won’t go back. For me, it’s easier than Titebond given the long term repair implications. There are very few joints where I don’t use HHG. I use the LMI PVA glue for the endblocks and usually the linings (just for the working time advantage). Sometimes, I use Titebond to install a rosette. I use it installing frets. Other than that, you won’t find it in my guitars.

If you decide to use obg you should to heat it too. It just gives you more working time due to the urea.

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Jim Watts
http://jameswattsguitars.com

Good going Peter I think you will enjoy this.

We use Rival hot pots to heat our glue and keep the glue in baby food jars. We use so much of it that we mix fresh batches as necessary and don't try to keep it very long although we do store the excess in the fridge.

I'll be happy to help you learn to use HHG too Peter including a little gem that we use that Dave came up with to preposition all your clamps in advance so all you have to do is slap down the bridge and snug the clamps. We can do this in 5 seconds if we are trying. Takes the stress out of the short open time.

Let me know with PMs is I can help and I am always happy to do so.

I've gotten a wonderful amount of advice and encouragement. Thanks, everybody!

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Peter Havriluk

Just get a coffee cup warmer on Amazon for $10. I think you have about 1 minute to get everything clamped, maybe more if you heat your bridge up in the microwave first. The cleanup is a breeze with hhg.

Hesh, you guys using 192?

Commando with the hot pipe turned off, lol

Pat

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Pat

That's what I've been using as well. They're all over the place at Amazon. I'm passing along a tip I got here : put some glass marbles at the bottom, it really helps keep temperature stable as well as elevate your glass jar so it won't be in direct contact with the heating element.


Pierre
Guitares Torvisse

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Pierre Castonguay

Hey Hesh, don't keep that nifty trick to yourself…


Pierre
Guitares Torvisse

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Pierre Castonguay

This photo shows how I do it. After the bridge is fit to the top I do a few prep steps:
1. Tape on the top protects the top from the clamps.
2. Tape over the top of the clamps keeps the clamps in place when they are loosened so when I'm ready to glue on the bridge I can just slide the bridge in and tighten the clamps.
3. The tape around the bridge lets me locate the bridge instantly when I glue it and also makes it easy to clean up most of the glue squeeze-out.

Glueing on the bridge:
1. Once the clamps and tape are all set and bridge is ready I give the top area and the bridge a final scrape.
2. Bridge and the guitar have been under a heat lamp so the temp is around 100F or a bit more.
3. All is ready now so I put hide glue on the top and smear it around with my finger then put hide glue on the bridge, set the bridge in place and tighten the clamps. Takes longer to type it than to do it.
4. I let the hide glue gel a bit, like maybe a minute, then pull the tape around the bridge to get most of the squeeze out.
5. After about five minutes I use a rag dampened with a bit of hot water on it wrapped around a stick to get the rest of the squeeze-out cleaned up.
6. I leave the bridge clamped for 24 hr.

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Steve Smith
"Music is what feelings sound like"

The tape on the clamps to keep positioning trick is great, thanks Steve. I'm using the same SM clamps and place an 1/8 acrylic sheet under the secondary clamp feet. Better safe than sorry.


Pierre
Guitares Torvisse

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Pierre Castonguay

I like the acrylic idea, better than tape!

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Steve Smith
"Music is what feelings sound like"

I have a lot of acrylic pieces I'm using as cauls on tops while regluing braces and leveling cracks. A 12x12 scrap piece will go a loooong way and yield many very useful pieces.


Pierre
Guitares Torvisse

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Pierre Castonguay

Another trick I got from some nice person here… HDPE stuff can be bought in sheet of varying thicknesses and is ideal to make cauls. Nothing sticks to that stuff.


Pierre
Guitares Torvisse

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Pierre Castonguay

I’ve got both laying around just wasn’t using it for bridge reglues.


Steve

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Steve Smith
"Music is what feelings sound like"

Nice to see someone appreciate my attempts at humor

Yes 192.

We use 15 seconds as our benchmark to have all clamps snugged down and be able to walk away from it. It can be quite the dance at times with big repairs but it's worth it.

No I won't and I have lots of classified documents at my house too

I don't have a pic of it but I think Steve Smith might? Steve if you do have a pic of Dave's set-up to glue a bridge with HHG please post, thanks man!!!

Anyway it's a method to preposition clamps with blocks and tape AND make a masking tape well of sorts so you can slap the bridge down and snug the clamps in seconds with everything exactly where we want it. Works great. It's also easy and easier to clean up with great access and much of the squeeze out comes off with the tape.

I will post about though, you bet.

Thanks Steve!!!!

Now we do it for steel string bridges with only one BAC (big ass clamp) and the StewMac bridge glueing caul. As Steve has done here you can add clamps for the wings too.

Hey Hesh, unfortunately I didn’t get a photo of Dave’s bridge gluing setup.

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Steve Smith
"Music is what feelings sound like"