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Has anyone used this according to the mix instructions on the back, or do you have your own mix ratio? I mixed it according to the instructions on the back but I don't trust the joints I am getting. I heated it in the glue pot, I took a few pieces of sitka spruce, pulled the glue bottle out of the pot put glue on a piece of spruce attached another piece clamped it right away left it sit over night. I did that with two seperate pieces. One set of glued pieces pulled right apart, the other piece I set on the concrete floor and wacked it with a hammer a couple of times, the wood split for about half of the joint and seperated at the joint on the rest of it, but I could pick the wood splinters off of the joint leaving a clean joint. This was a dumb test i'm sure . Before I start using it on my guitars I want to make sure I'm doing it corectly. I don't think I could have glued it together any faster than what I did, I was standing right next to the glue pot with clamp in hand. Any advice would be appreciated. Thanks.

I use Behlens, and I'm by no means an expert, but it doesn't sound like you got good joints. All my tests resulted in the wood coming apart, not the joint. I mix in little squeeze bottles with a stainless screw inside to help it float upright in the hot water bath. I started mixing the glue on a scale by putting in equal weights of glue and distilled water. Now I just add distilled water slowly until the water just covers the top of the glue. I let the glue sit in fridge overnight then heat in a little crock pot full of water at 140 degrees F.

I've had better luck with my glue joints (i.e. I haven't had any fail) when I warm the wood up first with a heat gun although a hair dryer should work too.

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Steve Smith
"Music is what feelings sound like"

Just to let you know...most builders use a different HHG than Behlens. Most use 192 gram strength (from LMI) whereas Behlen's is 252 gram strength. Theoretically both work fine, but the 192 gives a longer open time before it starts to gel. If you get the parts together after the glue has gelled, you'll get a poor joint. Steve is absolutely right on point when he recommends warming the parts prior to applying glue to give more open time.

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

First make sure the glue is hot enough. If you have a thermometer, put it in the glue not the water.

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Build log

You can often take apart a hide glue joint with shock (hammer), even on a pretty good joint. The stuff's hard, harder than the wood around it, and so it'll shatter if put under intense shock.

That said, the other joint coming apart is a bad omen. Hide glue, in a good joint, is much more forgiving than is commonly believed. Even very dilute glue will hold together a good joint quite well (ex: half the joints on a violin).

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

I use Behlens. I normally mix 50 grams glue with 88 grams of water, and add a pinch of salt. The salt gives you a little more open time, but reduces strength a little, probably making it the same as 192 gram. I warm the pieces I'm gluing either with a heat gun or a bending blanket with the thermostat set pretty low. HHG doesn't fill gaps well, and you have to get it clamped before it gels.

FWIW I also add a couple drops of vanilla extract to the mix to help with the smell.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I dunno - I kind of like that hide glue smell - reminds my of my old family dog, when we'd let him come in from a really hard rain and let him sit in front of the fireplace.

I add red food color and call it Jello.
Everybody loves Jello.

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Thanks for all of the replies. I know it's not the glue also. It was just my method. I had mixed the glue up that morning and that afternoon I glued up the test pieces, but since it sat in the fridge all night and then I put it in the glue pot this morning heated it up, did some test pieces that are holding up great. I'm just a chicken sh@! that's all. I did glue up some braces on a soundboard this afternoon, It seemed to go well, but hey I figure if I screw it up I can heat it up and do it again. Thanks again for the replies I appreciate it.

Woody, with the scale I used I mixed 1 oz. of hide glue with 1 oz. of water by weight. I'm going to have to try to add some salt on the next batch.

I didn't notice a smell, but then again I don't mind the smell of skunk. Weird.

But this freezer thing should not be necessary. 100y ago there were no freezers, right? Let it soak for 1-2h, heat it up and it should good to go.

What consistency is it at 1-1 mix ratio? I would imagine it is very thick? I've been using about 1 to 1.7 water and it can still feel thick (for me) after some water evaporates during the few hours of constant heating.

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Build log

That's pretty dry. The man that taught me years ago said to mix equal amounts of glue and water, by volume, not weight. Usually by weight it's about 1 part glue to 1.8 parts water. I don't know if this will effect strength or not.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I said I started out mixing equal parts by weight but that's been awhile and it sounds like I didn't remember correctly - sorry. Now I just pour some glue in then put water in till it just covers the granules. When I first heat it, it's a bit thin but thickens up after several days. I just use it and pop it back in the fridge then reheat the next day. I'll use it for about 6 or 7 cycles or about 10 days max then I make up more but I'm just doing this in the evenings and on weekends. It seems everybody has their own favorite ratios and all so just use the method that works best for you.

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Steve Smith
"Music is what feelings sound like"

This is what the can says " Add equal weights of dry Ground Hide Glue and water" It also says "If necessary, add water to increase setting time." Very vague, increase as in a faster set time or increase as in longer set time.

The 1:1 mix ratio I would say is, it comes out of the bottle runny, it will run all over so I keep the piece level. when I apply the pieces together the squeeze out is kind of like honey, if you touch the squeeze out right away it will smear, if you wait about a minute or so it will ball up and come off clean.

I bought this can of glue in Nov. of 06, I tried one other time to use it but chickened out. This time failure is not an option!

I haven't read the can in years, but are you sure it says "weight" or does it just say equal amounts? I'll look at one of my cans later. I apply the glue with a brush, and it's pretty thin. The main things to watch are, make sure the joints are tight. Be sure you get the pieces clamped before it gels. Mess with some scrap wood, and you'll easily figure out how long you have to assemble stuff.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I just mixed some up and it does say equal weight. I use 1oz squeeze bottles; I don't need very much today but I put in the glue then added water until it just covered the glue. The result was 13gm glue and 15gm water. So I guess that's why it's a bit thin at first but it works for me.

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Steve Smith
"Music is what feelings sound like"

I used the Behlen's hot hide glue for the bracing on my last build and like everything except the fact it jells so fast, I will get some 192 for the next build. I was going to try it for the bridge and neck joint but I don't think I am fast enough for that. After watching Mario glue a top on with the 192 glue I think the Behlens has only 1/2 the working time so when I get the extra working time I might be fast enough. I worry so much about joint perfection I tend to fiddle around to much while gluing.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I am not sure the difference in open time between 192 and 251 is substantial. Behlen's hide glue is what I use, and what the shop I used to work in used, never seen an issue.
I mix it by feel, and keep adding water to get the consistency I want depending on the task, it's pretty forgiving.

Working in a warm shop is the main issue, and a heat gun to warm the pieces before hand is mandatory for most glue jobs. The heat gun can be used to re-warm the joint after brushing some hot water on it when in doubt, and to clean up squeeze out. Old-timers used an alcohol lamp, same concept. For the French reading Robert Bouchet "Cahier d'atelier" is a great read, he did everything with HHG, even binding and purfling, not that he had much of a choice back then.
Otherwise a 200W hallogen lamp over the bench really helps keeping the work pieces warm.

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

For those of you who are struggling with the open time of HHG, consider Fish Glue. Even though I had my technique down with HHG and never had problems gluing on tops and backs, I now really like the ability to have more open time with FG. After 3 FG guitars, I have seen no qualitative difference in joints comparing the 2 adhesives. Nonetheless, I still use HHG for braces and other operations in order to use up my 10 lb. HHG stash!

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