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Here's an interesting article I found on the process of making hide glue. Don't go burying fido yet if he kicks the bucket. There's at least a good batch of hide glue in there...

Quoting "Hide glue made from animal hides. Yes, from animal hides, almost any animal but primarily from cattle hides. This is simply because of the abundance of cattle hides due to the enormous world wide consumption of beef and subsequent tanning of hides for leather. The trimmed hide pieces (too small or irregular shapes to provide useable leather) are shipped to the hide glue plant.

The glue manufacturing process is basically the following:

wash to remove dirt
soak in lime water for 60-90 days
wash to remove hair and lime
neutralize with acid, drain, wash & drain
add water, heat to 110-120 deg. F for 2-4 hours (called an extraction)
drain off the dilute glue solution, evaporate, chill, dry, grind
repeat last 2 steps 3-4 times to extract all of the glue with the temperature being increased 20-25 deg. F each time.

Hide glue is a protein derived from the simple hydrolysis of collagen which is a principal protein constituent of animal hides. Collagen, hide glue and gelatin are very closely related as to protein and chemical composition. An approximate chemical composition for glue is:

Carbon 51-52%
Hydrogen 6-7%
Oxygen 24-25%
Nitrogen 18-19%
Total 100 %

The molecular weight of hide glue has a wide range from 20,000 - 250,000. The higher the gel strength, the higher the molecular weight.

[QUOTE=John Elshaw] An approximate chemical composition for glue is:

Carbon 51-52%
Hydrogen 6-7%
Oxygen 24-25%
Nitrogen 18-19%
Total 100 %
[/QUOTE]

You forgot cooties!

Wooo, man, that sounds like a discovery channel "Dirty Jobs" segment.
I'll stick to driving to Woodcraft and dropping a ten spot on a pound of granules for now.
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

So let me get this striaght when my dog dies whatever part I don't turn into leather I should turn into glue? In NYC we have rats, I am thinking 1 rat per bridge reglue. According to the latest statistics that would be 17 million bridge reglues! Or of course 1 J-200 bridge
Luthery is creepy!
Evan

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http://www.NewYorkGuitarRepair.com

My neighbor stopped in the other day and was surprised to see I was building guitars. She told me a story of her father who built violins in the mid west a million years ago and of course he had a secret hide glue recipe that he kept brewing in the shop. Turns out he had a few chunks of hide smokin away, always ready for the next glue joint. She had no idea how it was done but I'll be happy to try it with a credit card and a shipping address when the time comes.

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Thank You and Best To All

If Ed Geim (sp) had only known about this glue production...

Ed Gein

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

Hmmm... Lotsa cows in Montana...   

-Mark

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Pullman, WA

The more I know, the more I know I don't know.

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hmmm lots a deer in Oklahoma...

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John Mayes
http://www.mayesluthier.com

Scary for me in Canada...

Da Bear

Lots of road kill (possums) in South Carolina.....