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Hi Guys,
Well, I've come to the crossroads of mixing hide glue.
I purchased a can of Behlen's dry hide glue. The directions say to mix equal parts glue flakes and water "By Weight".
My problem is that I don't have a scale.

Now what?
Is there a way to do this without a scale.
Also, do I put the final product in the frig until I am ready to use it?
I would appreciate any help from you veterans of hide glue users.
Thanks,
WalterK

if you have two small identical bottles, string and an old ruler make your own balance. i keep out what i will need for the job at hand and freeze the rest in job lot size plastic bottles.

Kitchen supply stores have reasonably priced accurate scales. It's worth the money to get it right.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Walter, I'll be the odd man out here....

I stopped measuring sometime ago, I simply fill my little bowl (it's a tiny litte tupperware thing I stole from the kitchen) with hide glue to the level I want and fill it with distilled water to the top of the hide glue, then let it melt and mix. Then if needed I adjust the consistency until it's where I like it, I used to put Urea in to give it a longer set time but have found that you really don't need it if you get the consistency right. I don't know if I can describe what I'm going for but I like it "runny" or somewhat thin..

I'm sorry but I just don't think it's that important to get the ratio's perfect, and since I like mine just a little thinner than most because I find it easier to get good joints, when it's too thick it gels way to fast.

Also keep in mind that when you leave it in the pot heated, it evaporates constantly so your ratios are never going to be spot on anyway as you'll have to add water to keep it workable..

Cheers

-Paul-

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-Paul-

Patriot Guitars

Paul makes some very good and valid points....

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Do you want the consistency of say..pancake syrup?
I'm going to use it for gluing the bridge on.
Maybe a little thicker?
Thanks for everyone's help.
Walter

What Sprokett said with a few clarifying points. I let it dissolve overnight in a covered container. Next day I heat it up until it forms a uniform solution and then pour it into small containers so that there is no headspace. I then bag the containers in a freezer bag and store in the freezer until ready to use.

Make sure you use distilled water as Sprokett specified.

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

Why distilled water?

Why no headspace? (Freezer burn worries?)

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

JJ how long a shelf life would you give it, in its frozen state? 12 months? 16, 24? Indian?

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Lance@LuthiersForum.com

[QUOTE=WalterK] Do you want the consistency of say..pancake syrup?
I'm going to use it for gluing the bridge on.
Maybe a little thicker?
Thanks for everyone's help.
Walter[/QUOTE]

Good question... It comes down to a couple of things with Hide Glue (I'm waiting for Alan to chime in here and correct me if I'm wrong)...

1. How fast can you *reasonably* clamp something down BEFORE the glue starts to gel.

2. How thin can you really make it before you lose integrety of the bond.

When I very first started I was afraid to make it thin, so I would glue and slap the piece down and frantically clamp away. But over time I found that by thinning it out and gettings things at least warm (all the parts) I would get longer set times and I could not discern any difference in the joint strength. That's important for two reasons:

a) The glue needs time to penetrate the wood to create a good solid bond (I'm not talking soak here, I'm talking about it getting into the fibers and pores and things).

b) Once it starts to gel it's over, if you have not clamped it by then, take the piece off, cleanup and try again (done this more times than I can count).

Once I learned that little trick I've not had any real problems, other than the occasional bonehead move

For a bridge I like it just about like syrup (maybe a little thicker) and HOT, I keep it right at 145 degrees (the limit of what I have read), I also put my bridge in a heating blanket and get it nice and toasty as well.

Once I apply the glue to the bridge I have about 1 minute to set and clamp, for me I use guide pins and a vaccum clamp so that's easy but I could do it with regular clamps, just be sure to practice first to work out any kinks. I also like to see some squeeze out when I cleanup, it tells me that I had enough glue on the joint, I use a china bristle brush and give it a good even coat and then glue it down.

Distilled water is because you really want the glue to be as pure as you can, our waters pretty good here but in a pinch I will use filtered water from the fridge but never tap water, you don't want things in the water mixing with the bond your trying to create.

Also one other thing about hide glue, give the glue time to set and especially with things like bridges. I don't even touch a bridge until at least 24hours, you want to give it time to evaporate off as much moisture as you can. For braces it never less than an hour before I move onto the next.

Also I don't freeze my glue, I make small batches and when I'm not using it leave it in the fridge, I've done this for weeks at a time before re-heating. I don't think there's anything wrong with this approach, I just don't find the need to do it.

Cheers

-Paul-Sprockett38566.7709027778

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-Paul-

Patriot Guitars

I never use a scale either. In a small baby food jar I fill the bottom with hide glue and add water until the glue is just barely covered. I then heat in one of those mini cheap crock pots and stir with a chop stick. If it is too thick I'll add some more water until it looks like warm honey or thin maple syrup consistency. I haven't had any problems using hide glue, but you do have to be quick and you do have to worry about the working time. Take some time to experiment and find the right consistency and working time for you. Good luck!
Tracy

Hey Guys...Thanks for your informative post's on this Hide Glue subject.
Sounds pretty scary to me! Oh what the heck..I'll give it my best.
Thanks again, Walter

Hi Guys

I have a question on this one, my only experience of mixing hide was in the shop of another builder, and he use to make it fresh in a pot. When you talk about using it in bottles do you heat it up in the bottle when you want to use it ?

I haven't done it yet, but I'm planning on using small plastic nozzle bottles with a bolt in them for a) weight and b) to help them hold on to some heat (thanks to Mario for that one), and bottles because, well, I don't think applying with a brush would be much fun. I think most people use their glue 'au bain marie', heating a glue container (disposable) in a water bath kept to a certain temperature, and more and more people seem to be using small squeeze bottles rather than brushes.

for what its worth, you can get a Rival Hotpot 12.00 bucks at your local Walmart, for a gluepot. Works great!

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Lance@LuthiersForum.com

Lance...RE: Freezing. I've thawed out hide glue and heated it up after 3 months with no problems. I actually did a controlled test (2 pieces...not statistically significant) comparing the bond strength to freshly made stuff. All samples tore wood. With all due respect to Mario, I suspect that it can go a lot longer and will test it again sometime at various times with 13 samples (statistically significant). I let it thaw gently at RT first and then heat it up.

Brock...RE: Distilled Water. What Sprockett said. In a high school chemistry class, my experiment failed to produce the expected results. Sister Margaret Mary asked if I had used tap water. I reluctantly admitted my lazy mistake. She informed me that in chemistry, we ALWAYS use pure water to avoid unexpected reactions with minerals, chemicals and trace metals. This lesson carried over to my darkroom work and now hide glue mixing.

RE: Headspace...Air will cause oxidation and freezer burn in solutions, food, etc. Some people actually use nitrogen to replace the air headspace in paint to prevent oxidation and extend its life. I find it easier to displace the air with fluid...so once I remove a bottle from the freezer, it never returns. Just another quirky habit I've gotten into.

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

Hey Lance...

You know I used one of those for a while but I had to keep a thermometer on it at all times because it was touchy, I finally spent the $90 to get a glue pot and put my digital thermometer (that I stole from where else but the kitchen) and after two weeks gave up because it NEVER went above 145 degs. Now I don't worry about it and the chicken does not get burned any longer

The squeeze bottle thing is a Mario trick that works really really well, I use both a bottle and a good brush and flip back and forth based on what I am gluing.

Finally just think of hide glue as a food product, if you treat it like that you'll be just fine. When your not using it, refrigerate or freeze and keep it moist and warm when you are, make sure to give it a good sniff once in a while to make sure it's fresh and your good to go. Bad hide glue smells well....BAD...

When I'm really busy I change it out more often and I've left it sealed in the fridge for literally weeks between gluings...

-Paul-

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-Paul-

Patriot Guitars

BAd hide glue smells bad? Heck good hide glue smells bad. :P

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John Mayes
http://www.mayesluthier.com

IMO what counts in the glue line is how much of what quality glue you end up with between the pieces. Glue is not really a strong material in bulk, so you don't want too much in there, but, on the other hand, you need enough to get the chemical bond. Thick glue or a large glue surface will require more clamping pressure to get the excess out. With thin glue it's easy to get a 'starved joint' on thin or hot pieces. Old, dark glue is nowhere near as strong as new, light, clear stuff, and thinning the pld glue out just makes it weaker. I use that stuff on fiddle tops and fingerboards that I want to be able to get off anyway.

Once the liquid glue gels that is the structure of the joint. As it loses moisture it will shrink and get harder and stronger, of course. If you move the parts after the glue gelled you broke the joint, even though the stuff is soft. All you have to do to get it back is to warm it up, or you can take it apart and re-do it.

So what you're looking for is the right combination of glue thickness, heat, and clamping time and pressure, to get everything done with the 'right' amount of glue in the joint before it gels. With all of those variables, there's a lot of leeway, and what works for me might not work for you. Fortuneately, unlike building a wooden airplane, if your glue lines fail nobody will die....

A thick mix, like what they tell you to use on the can, is fine for furniture makers where some gap-filling is useful and they use honking big clamps to hold large parts together. We usually go for pretty fine tolerances, and often make little tiny parts that can't be clamped hard, so we use thinner glue. Or, to look at it another way, because we're making little pieces and can't pull them in with big clamps we have to make them fit really well, and thick glue would end up making a heavy bond line.

There's a bit of a learning curve with hide glue, but it's not that bad. So long as you get it clamped before it gells you should end up with a decent joint so long as there's enough glue in there. A little thick is probably better than a little thin.

If you think hide glue smells bad, try sturgeon glue....