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I really like this stuff. So easy to use.

Question: is it as good as normal hot hide for bridge attachment??

My planned uses are bridge and fingerboard.

Mike

Following. I’m not using it as much as I first imagined. I keep it in the fridge and it’s thicker than molasses at this kind of temp. You then have to heat it up to around 120° before it’s usable and then… why not use HHG instead?

I like OBG a whole lot apart from the temp issue, but this might very well be my own fault. I’m waiting for the others to chime in.

Maybe I should keep it at room temp and use it as an everyday glue instead of fish? What’s everyone's experience with OBG?

To the OP… I’d consider OBG just the same as Liquid hide from Titebond as far as bridges… I may be wrong about this but you know, I'm not taking any chances with bridges.


Pierre
Guitares Torvisse

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Pierre Castonguay

That is absolutely not the case. I have been using it for bridges for 3 years now. It is far stronger and higher quality than the Titebond garbage.

I've not noticed a difference between it and HHG for bridges. If you don't do a good job of getting the joint fit well it won't stick no matter what type of glue you use.

Hey Dan, happy to get a documented opinion about this.

I get from what you're saying that the main difference with HHG would be in longer open working time, without any drawbacks from the added urea? Is that your opinion from experience?

I know the Titebond LH gets quite a bad rap, but before I turned to fish as my go-to "bench glue" I used it quite a bit for low-stress applications and never had a problem with it, but yeah, I moved on fearing problems down the line.

Also, do you keep it at room temp so it’s readily usable on your bench? It's quite thick even at room temp, so you have to heat it up anyway, don't you?

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Pierre Castonguay

Yes the open time with OBG is much higher therefore much easier to work with too. You can heat it up if you want but I just use it at room temp. Brushes are good for spreading it around when it's cold and thicker. The urea seems to lower the gram strength of it a bit but not nearly enough to create a problem. When I was first getting into hide glue I once made my own from rawhide dog chews (the kind you can get in bulk) and while it was very strong it had maybe a 5-8 second open time which was awful to work with trying to clamp things together.

Fish glue I have seen fail quite a few times. It's good for certain things that aren't under stress but if you can use hide glue with OBG or HHG I always recommend it.

Great, thanks.

I have just gotten some OBG that I had poured into a small bottle out of the fridge, dunked it into my hot water bath warmer and presto, 10 minutes later it was workable. Still not nearly liquid enough as my HHG from this morning, but I could have waited a bit more to get temp higher still. This was much faster anyway than getting precooked HHG cubes from the freezer. I used it to finish a job I had started with fish just this afternoon. I found OBG to have quite a bit more tack than fish but it still allowed for parts to be moved around a bit before settling. I liked it. Never had a problem with fish for lower-stress glue-ups but then I never tried it on bridges, headstock cracks and such.

I'm going to have a go with OBG as my bench glue for a few weeks I think. Thanks for your helpful comments, Dan.


Pierre
Guitares Torvisse

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Pierre Castonguay

I use it for box closing and binding, and don't treat it any differently than regular HHG. Heat it in the glue pot before application, and reheat after getting the clamps on. Particularly with binding, regular HHG gets quite messy with lumps of gel everywhere. OBG squeezes out pretty well even after it cools, but still a little more comes out after reheating, so I wouldn't be comfortable using it at room temperature. Though I didn't reheat the first time I used it for box closing, and it still held ok. But it also made me nervous that the squeeze-out never completely dried (even after weeks), just turned sort of rubbery. It seems to form a waterproof film on the surface when exposed to air, which burns off when reheated and doesn't re-form (then it dries hard like regular HHG). It's actually quite useful, since it slows the drying time while working. Even without worrying about the gel time, HHG is still a bit of a hurry to get to the reheating step before it dries out.

Hey Dennis,

How do you go about reheating?


Pierre
Guitares Torvisse

_________________
Pierre Castonguay

Hold it over an open flame on the kitchen stove. Keep it moving so as not to char any edges

It' don't mean a pile of poo if it ain't hot hide glue.

I come at this question from a slightly different angle. Let me explain.

Old Brown Glue (OBG) is great stuff in that we know what is in it. It’s hot hide glue with enough urea added to make it a gooey liquid at room temperature. Not all store-bought glues are that simple.

My perspective is that you should add enough urea to hot hide glue in order to accomplish the task at hand, but not add any more than that. Why limit the amount of urea? Because the glue doesn’t really act exactly like hot hide glue when it has an excessive amount of urea in it. It’s glue, but it doesn’t work like hot hide glue. It takes a long time to firm up (if it ever does), and I can’t say for sure, but it feels less secure. So, I only add that much urea when I need a super long open time, like when I’m constructing a rosette or custom purfling.

For something like a bridge, I don’t need any urea; I can get the joint glued up in seconds. If I don’t need it, I don’t use it. Or if I had a concern about having enough time, I would maybe add enough urea to make up 5% of the weight of the dry glue I used to make the batch. But OBG has a lot more urea than 5%. For me, it is not the right glue for this particular job; it has way more urea than this job could ever need.

Then there is the cost of OBG, as compared to making your own. You really are paying a lot more for having it come in a premixed bottle. And you have to keep your eye on the expiration date, which is not a concern when you make it yourself.

If somebody gave me a fresh bottle of OBG for free, I would gladly use it for those hot hide glue jobs where I need a super long open time. But gluing on a bridge is not in that category, so I wouldn’t use it for that. I’m sure there are folks who successfully glue on bridges with it; I just wouldn’t go that route myself, for the reasons stated.

Well, I like to ask this question every so often to see if there are adherents. Someone here seemed to like it. But most are wary. I think I have my answer. I’ll start using HHG for bridge and finger board extension.

Thank you.

Mike

Sounds like a great idea.

It's really quite easy to make your own HHG extend, shall we call it? I use canning salt. I cannot remember the exact weight percent off the top of my head but basically you mix in salt while you cook the hide glue. It doesn't take much and what you end up with is HHG with considerably longer open time. At room temperature the glue is not a liquid but when you heat it up it's a nice running honey liquid and stays open long enough to glue a back on. I use it for just about everything now.

I don't use my preferred "extender" (urea) all the time, but as I mentioned above, if I have any concern about having enough time to get the clamps on, I will add urea that weighs 5% of whatever amount of dry glue I used to make up the batch. That extends the pre-gel time long enough to where clamping time is really not something to worry about, and it is not enough urea to make the glue act weird. It just extends the pre-gel time with no bad side effects. Pretty handy.