Suggested glue to use for a bridge?

Misguided Musician

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I don't know if any kind of glue would be fit to glue the bridge back on, but I want to do this with a proper one that won't come off so easily. What kind of glue do you suggest to use? Is there a certain kind that is needed for such a repair job?
 
Ahhh - the hide glue evangelists! Hide glue is the best if you want to take apart an instrument. For violins it is THE glue because unlike fretted instruments they need constant attention and in the long life of a member of the strings family it should be taken apart at least once if not more... Now a ukulele? I'm not convinced about hide glue since a friend's violin fell apart in the tropics. It has a limited shelf life and you need specialist equipment and a good knowledge of how to prepare and use it. Aliphatic resin glues are fine and the advice about cleaning the mating surfaces is spot on. Glue joints in wood are 'mechanical' and rely on a wood to wood relationship.

If you search through publications of Fine Woodworking to August 2007 issue 192 there is a brilliant article that deals with testing of the bonding strength of 6 common used glues. The results are quite a surprise with the much criticised Titebond hide glue proving better under the test conditions than traditional hide glue and type 1 PVA scoring above them all.

Like many things to do with lutherie there is a huge amount of received wisdom and traditional belief. There is a place for hide glue for those who can demonstrate their skill in using it. For me, the technology has moved on and I with it. I will never use hide glue except if I went back to furniture making working with highly figured burr veneers.

And just ask yourself a couple of questions to get some perspective on this: Why do Collings guitars epoxy their fingerboards to the neck? Why is there a proliferation of carbon fibre re-inforced necks when I have NEVER seen a stress bent ukulele neck?

Tradition is not necessarily always the best source for a contemporary solution...
 
Ooo haha falling apart in the humidity would suck, and you are correct about getting the glue mixed just right. It must have been awful humid for quite some time, cant imagine that that was good for any part of the instrument.
 
Or, something like this:

bridgerepair.jpg
 
Original Titebond is all you need.

Hide glue is the best, but if you are not using it often its not worth it for the effort. I use a cheap double burner to melt the hide glue pellets and let it cool down when I'm done. When the pot starts getting low I just throw in more pellets. It takes about 30 or so minutes before I can use the glue. I guess it is about 10+ years that I'm using the same pot.

BTW, yellow glue (titebond) and white glue (elmer's) really only has a one year shelf life. So buy only as much as you need.
 
Glue for repair

Theoretically hot hide glue is best not because it is strongest (it is not) but because it is the least flexible joint, thus damping vibrationsthe least. In fact, I defy anyone who does not know what was used to hear the difference. Having done more than 50 bridge regluings on steel string guitars I would recommend something like titebond. I've never had one fail. As said above, clean off the old glue and get as close a fit as you are capable of, use a caul to clamp against inside the uke, and clamp with moderate pressure. Let it sit for a day before you restring it.
 
Theoretically hot hide glue is best not because it is strongest (it is not) but because it is the least flexible joint, thus damping vibrationsthe least.

And this is the reason why epoxy is the worst glue. I've used epoxy on wood and I have noticed that it "creeps" or "moves" the most. I have seen joints that where perfectly smooth and a year later I can feel the glue line. In three years I have seen pronounced movement in the mating surfaces.
 
Not to mention that in some cases you would prefer the glue to fail before the wood.
 
The forces on a bridge are a combination of shear and torsion. In this situation and according to Fine Woodworking report where the test method was a shear action, PVA is the best best. It is more forgiving than hide glue which requires an 'absolute' fit. When replacing components, unless you are some sort of genius, a perfect mating surface is often unachieveable; there will be a few low spots etc caused by the cleanup...

PVA has convenience above everything else. It is an industry standard and as RonS says, does not creep and unlike hide glue is not brittle.

I admire people like Dave Means who uses hide glue. If I could see any benefit over PVA to doing so myself I would also use it. However, a University degree in craft based woodwork and metalwork with modules in timber technology, the history of the classical guitar, materials science etc leads me to conclude it's not worth the effort FOR ME. I salute you all and especially Frank Ford who writes so eloquently about this old technology.
 
I can confidently say that 5 minute epoxy and med. viscosity cyano does not work for more than 6 months and titebond 1 has worked for several years and still counting. Interesting how we tend to learn what doesn't work or how not to do something before we learn how to do it right. Or is that just me?
 
Just you - there are hundreds of Hurd ukulele out there with an epoxied butt joint for the neck to body connection...
 
Interesting how we tend to learn what doesn't work or how not to do something before we learn how to do it right. Or is that just me?

Nope.

There are two ways to learn.
1) By our mistakes
2) By asking others and learning from thier mistakes.

----

Remember Beta-max and VCR Tapes?

Beta-Max was technically better than VCR in both sound and picture clarity. But VCR won out because it was cheaper. Just because something is marketed don't assume that it is produced in the best way possible.
 
Original Titebond is all you need.

Hide glue is the best, but if you are not using it often its not worth it for the effort. I use a cheap double burner to melt the hide glue pellets and let it cool down when I'm done. When the pot starts getting low I just throw in more pellets. It takes about 30 or so minutes before I can use the glue. I guess it is about 10+ years that I'm using the same pot.

BTW, yellow glue (titebond) and white glue (elmer's) really only has a one year shelf life. So buy only as much as you need.

I use the Titebond hide glue. I love the stuff. And if I miss position the bridge due to a rough night before, I can always steam it off and re-position it. I wished that my beloved G-string bridge had hide glue when assembled. Had to compensate for someone else's rough night before...e.lo..
 
Thank you for all of your suggestions.

Now to add to the problem. There is some splinering left behind from the bridge tearing away from the body of the uke. How should I deal with the splintered wood?
 
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