Natural tanning

[Dick Sexstone]

I'm wondering what the difference is ,or if there is any difference between vegetable oil tanned and brain tanned leather is? I'm wanting to make a scabard/sheath that will be less

 

likely to rust the blade... From I have read the natural tanned leathers are less prone to rusting the blade... I have no experience with leather so any info will be helpfull

 

 

Thanks,

 

Dick

 

 

 

 

[Matt Bower]

Dick,

 

I'm no expert, but I've done some reading (enough to have determined that, sadly, tanning hides in a suburban townhouse backyard isn't likely to go over well with the neighbors or She Who Must Be Obeyed), and a little leather working. Weigh my input accordingly.

 

That said, AFAIK, brain tanning is just a form of oil tanning. Oil tanned leather is soft and pliable, and doesn't have a lot of body. It's not really "tanned" -- the leather hasn't undergone a chemical change. It's just been thoroughly cleaned, then treated with emulsified fat and smoked, which inhibits decay and (somehow) helps prevent it from getting stiff when it's dry, as rawhide would do. Oil tanned leather is typically used for clothing, because it's soft and remains breathable. It's not what I'd consider ideal sheath material. It's too soft to carve, and it won't hold an impression. Old-fashioned buckskin was oil-tanned.

 

Vegetable tanned leather is what's commonly called tooling leather, for reasons that will soon become apparent. It's been treated with tannic acid, which chemically alters the proteins in a way that makes them much less susceptible to rotting. It's firm and somewhat stiff, but its softens some when wet and will take and hold impressions. (You moisten it for stamping and forming, then let it dry.) You can carve and stamp veg tanned leather -- tool it, in other words -- and closely form it to a knife, a pistol, etc. This is the sort of leather typically used to make holsters, sheaths, gun belts, etc.

 

Modern, chrome tanned leather generally tends to be soft like oil tan, but has also been chemically altered to inhibit rot -- using some pretty nasty chemicals. It doesn't carve or take impressions well, and you can't form it to shape like you can veg tan.

Edited June 29, 2011 by Matt Bower

[Alan Longmire]

Not to mention chrome-tanned leather will eat a blade in no time if it gets wet, they don't neutralize the acids.

 

Veg-tanned is the only way to go for that sort of thing, even with the tannic acid (which "tans" leather, thus the name) not being terribly well neutralized.

 

Yeah, soaking a hide in a pit full of wet rotting oak bark will get you in trouble with the neighbors, etc. right fast. There's a reason tanneries were always outside the town!

[Matt Bower]

Actually, the smell of the bark liquor itself isn't supposed to be so bad; I think the tannins kill bacteria. I think it's mainly dehairing -- and the byproducts of scraping the hide -- that cause the really nasty odors. They used to use human urine for dehairing. Imagine what that smelled like after a few months.

 

Here's a good site for anyone who's interested in this sort of stuff: http://www.braintan.com

Edited June 29, 2011 by Matt Bower

[Dick Sexstone]

Thanks Matt & Alan,

 

Just the info I needed

 

Dick

[B Finnigan]

There is a old traditional tannery outside of London that does it old school. I think it was the show "Dirty Jobs" that showed how they used a tub of dog manure and water as part of the tanning process. Several of the steps involved their own unique and intense stench.

[Sean McGrath]

I think it was the show "Dirty Jobs"

 

Yeah, I watched that one. Mike just about got himself sucked into a couple of those old machines. That was one of the more interesting shows in that series so far. I didn't think he was in London though...?

[VaughnT]

Used to do a good bit of brain-tanning and wrote a few articles on the subject.

 

It's definitely an interesting material, but wholly unsuited for sheaths. The best you could do is use brain-tan for accents on the sheath, or to wrap around a rawhide/vegtan sheath. Good braintan isn't going to have any resistance to a sharp steel blade!

 

That's not to say, though, that you shouldn't try your hand at making some. It's certainly not something you want to do inside as the brain slurry smells, and that's not including the serious stench that you get from the rotting meat and fat that you have to remove from the hide prior to braining. Very smelly process until you get to the smoking stage.

 

Let me know if I can help any.

[Sean McGrath]

Very smelly process

I can remember my Grandfather experimenting with brain tanning when I was young. That's a smell that you never forget...

[Dick Sexstone]

thanks Brent & Sean,

I don't have TV but I'll have to find that show on the internet somewhere..

 

and Thanks Vaughn,

 

I already have myself spread too thin to get involved with another world of knowledge.... and it sounds like the smell might stop me anyway

 

Thanks for the info all . it is helpful

 

Dick

[B Finnigan]

It may not have been Dirty Jobs since it was outside of London. Most likely it was a History Channel program.

[Wild Rose]

That said, AFAIK, brain tanning is just a form of oil tanning. Oil tanned leather is soft and pliable, and doesn't have a lot of body. It's not really "tanned" -- the leather hasn't undergone a chemical change. It's just been thoroughly cleaned, then treated with emulsified fat and smoked, which inhibits decay and (somehow) helps prevent it from getting stiff when it's dry, as rawhide would do.

 

Actually such hides are tanned - the aldehydes (created from the tannins in the wood) in the smoke are what tan it though and not the oiling - it's one reason I don't care for the term brain tanned since as you noted the oils in the brains (the fat in animal livers, eggs, and other emulsified fats can also be used in place of the brains.) are used to soften the leather only - without smoking the oils can in fact be washed out and the hide will stiffen, etc. Thus smoking is what keeps it from rotting and getting too stiff). Some folks even use a pre-smoke method which tans it first then the oils are used to soften it - this is akin to veg/bark tan where it is tanned first then softend - the softening process is known as currying.

 

Real oil tan leather (not the so-called oil retan ) - such as the German Tan sold by Crazy Crow and others - is also in fact tanned since during the process the heat produced creates aldehydes as well.

 

In fact in most of todays tanneries the veg/bark based liquor used to tan is a formation of aldhydes as well. The old time method of layering hides and bark and then adding water i.e pit tanning, is still done today by some folks and at least a couple of overseas tannerys - if one would like to use traditonal pit tanned leather you can get it from RJF Leather, his supplier is from Portugal and the leather is very, very nice and comes in shoulders which helps save on overall cost.

 

As for chrome tanning - it's not as modern as most folks think - it was first developed in the 1860's...and yes the metallic salts and other chemicals used can and will promote rust, but the same can happen even in a veg/bark tan sheath when the piece is wet. Veg/Bark tan as it comes from the tannery to you is in fact around 4-5 on the PH scale so even it is slightly acidic, so overall yes it is never good to store a blade in a leather sheath for any length of time, especially if it gets wet.

 

Back on topic - as noted by others if you're going to make a sheath use either good veg/bark tan for the entire thing or if you wish to cover with braintan use a liner made from veg/bark tan or a rrawhide liner.

Edited July 14, 2011 by Wild Rose

[Stephen Stumbo]

It might be to late now, but another forum I'm a member of - Paleoplanet.org

 

Has a leather section, both the making of, and the working of, and the people there could tell you just about everything under the sun known about leathermaking.

[Dick Sexstone]

Chuck ,

 

Thanks , this forum is so cool... I should say the people on this forum are so cool...

 

Stephen,

 

Nope not too late ... I 'm slow on the uptake so you are just on time... Thanks for the link

Dick

[Matt Bower]

Actually such hides are tanned - the aldehydes (created from the tannins in the wood) in the smoke are what tan it though and not the oiling - it's one reason I don't care for the term brain tanned since as you noted the oils in the brains (the fat in animal livers, eggs, and other emulsified fats can also be used in place of the brains.) are used to soften the leather only - without smoking the oils can in fact be washed out and the hide will stiffen, etc. Thus smoking is what keeps it from rotting and getting too stiff). Some folks even use a pre-smoke method which tans it first then the oils are used to soften it - this is akin to veg/bark tan where it is tanned first then softend - the softening process is known as currying.

 

Real oil tan leather (not the so-called oil retan ) - such as the German Tan sold by Crazy Crow and others - is also in fact tanned since during the process the heat produced creates aldehydes as well.

 

In fact in most of todays tanneries the veg/bark based liquor used to tan is a formation of aldhydes as well. The old time method of layering hides and bark and then adding water i.e pit tanning, is still done today by some folks and at least a couple of overseas tannerys - if one would like to use traditonal pit tanned leather you can get it from RJF Leather, his supplier is from Portugal and the leather is very, very nice and comes in shoulders which helps save on overall cost.

 

As for chrome tanning - it's not as modern as most folks think - it was first developed in the 1860's...and yes the metallic salts and other chemicals used can and will promote rust, but the same can happen even in a veg/bark tan sheath when the piece is wet. Veg/Bark tan as it comes from the tannery to you is in fact around 4-5 on the PH scale so even it is slightly acidic, so overall yes it is never good to store a blade in a leather sheath for any length of time, especially if it gets wet.

 

Back on topic - as noted by others if you're going to make a sheath use either good veg/bark tan for the entire thing or if you wish to cover with braintan use a liner made from veg/bark tan or a rrawhide liner.

 

Thanks, Chuck. That was very educational and filled in some blanks for me. I assume that smoking doesn't tan the leather all the way through, though? I'm just guessing based on the fact that through-tanning with bark liquor takes much longer than hides are usually smoked, AFAIK.

[VaughnT]

The smoke can pass all the way through braintan that's soft and fluffy. Think about it like a knitted sweater with lots of gaps between the individual fibers. The only problem is that in order to do that, you will necessarily darken one side of the hide more than the other. The side that the smoke starts at will have more exposure time, thus getting darker, so we usually just turn the bag inside-out and try to get both sides about the same color. The two-tone look can be quite nice depending on what you're making, and it sets you apart from others that think uniformity is perfection.

[Wild Rose]

What Vaugh said re the smoking or it can just be smoked for a very long period i.e. in the West the tops of hide tipis, which get very heavily smoked were prized for making leggings and moccasins.