Thread: Natural Tanning

Have done both bark/vegetable and brain tanning, hair on and off. Mostly do bark tanning since I like it as a "hard" leather rather than a fluffy shammy type leather. Both are good with their own strengths and weaknesses.

Bark tanned leather is reasonably simple and produces a good leather product much like you would expect. Uses the same tannin that you have in black tea (it's why your mouth feels weird when drinking strong black tea, it's tanning your tongue and inside of your cheeks). Downside is that it can take weeks to months depending on the size and thickness of the skin and you need to monitor it throughout that time or you'll lose it. Can be used for all sorts of things that you would normally use leather for. I've had good success doing bark tanning on hair-on hides.

Brain tanned is nice in that it can produce a nice soft leather, much more suited for clothing. Uses brains as an oil-water emulsion to stop the hide from gluing itself together as it dries, but is sensitive to moisture unless you then smoke it to waterproof it. It's a lot more intensive to do in the short term, but can be done in a day or two if you know what you're doing and keep working at it. Because of this is more suited to people who don't have the space and time to do large longterm projects. It's not as suitable as a general leather product though - think of it more like a tough soft fabric than a hard leather, and it needs to be waterproofed to avoid going hard if it gets wet. Have never had great results doing a brain tanned hair-on hide, but others have. In general I don't do brain tanning much.

Both require a fair bit of focus to do properly. Natural tans are less forgiving of mistakes than commercial modern tans are, so you have to be a bit more fussy over your work to get them right. That said, people were doing it 10,000 years ago, so it's still achievable

Some tricks that will make your life easier and increase your chance of success:
- Reducing nicks or cuts in the skin, along with any fat or meat on the skin right at the start goes a long way towards making your job easier. Punching out a skin with your hand, or a paddle or spatula, is a great way to skin an animal without a knife (helping avoid slicing the hide, or leaving meat/fat on the skin). Imperfections in the skin make fleshing and softening more difficult. If you're skinning an animal to be processed by a tannery they'll be happy if you bring them a clean pristine hide.

- Storing the skin properly before working on it is also important. If you don't store your skin properly it can lose hair all the way to fully rot and dissolve. Most of the time you can't reverse degradation, so your best bet is to avoid it happening. Easiest way to store a hide is to just freeze the whole thing until you're ready, if your freezer can cope with a whole large hide. Keep in mind that a hide can take a long time to both freeze through and thaw out, so if you're doing a hair on hide then you need to cool it quickly so that the hair doesn't slip. Most slipping comes from bacteria, along with some skin breakdown, so best is to create a cool, dry, hostile environment to slow them down. Salt can help, as can acid, which both kills some bacteria and acts as a pickle to set the hair. If you're doing a hair-off hide as a leather product, then you're a bit luckier - hair slip happens first, then the skin starts to rot later. You can certainly salt then freeze a hide, but I have had issues with small freezers struggling to cool a hide and the salt didn't help... just drew moisture from the skin and created a pool of slushy liquid in the bottom of the freezer.... not nice, so beware. Thawing is a similar idea - if you thaw it slowly, the bacteria will start to slip the fur in the warm areas while the cold areas still aren't workable. Submerge your hide in a large source of salty mildly acidic water and routinely disturb it and pry it apart to thaw. If you don't want to freeze it, you can also stretch and salt a hide, but you have to watch out for any fat or oil in the hide turning rancid and burning the hide, beetles/bugs/animals eating it, and moisture causing it to rot/mold.

- Hair off hides can be immersed in a tub of water to let the bacteria slip the fur, or you can go a step further and make a basic solution which will force the hair to slip AND degrease the hide. A mildly basic solution is good enough - don't go too strong or you'll end up with chemical burns as you work the hide.... not fun...

- Processing the skin usually means at least some amount of fleshing and degreasing. You'll want to flesh the skin side of the hide and remove as much membrane as possible along with ALL the meat/fat. If you're doing a hair-on hide this' especially important since you're only really getting effective tan penetration from the flesh side, and traditional tanning solutions aren't all that effective to begin with. Meat/fat with straight up cause rot and destroy your hide, while membrane just acts like plastic food wrap and blocks tanning solution penetration which ultimately means your hide doesn't tan. Fleshing can be a real chore, so be prepared. I usually wear a rain jacket and rain pants, reduces how much miscellaneous meat bits end up on you. Any fatty animal will have a lot of fat in its skin, which will turn rancid and brown/black eventually and destroy the hide. Don't know what animals in NZ this would apply to - Bear and Raccoon are bad for it in North America. Deer should be alright, usually fleshing takes care of it. Scraping and mopping up with sawdust is the cheapest way of degreasing.

- Tanning is a whole giant discussion on its own - whatever you do, don't get lazy. Traditional tanning is time and effort intensive, so you need to keep on working the hide, agitating it in its solution, stretching it, etc etc etc. The time you decide "it'll be alright, I'll get to it in a bit" is the time it'll spoil, go rock hard and tough, etc.



Best bet is to start with rabbits, maybe possums, then work up to goats or the like. Rabbits are dead easy to tan, though the skin can be a tiny bit on the fragile side. It's easy enough to work that you can experiment without being shattered if it doesn't turn out, and it responds fast enough that you can see your results quickly, rather than find out you made a mistake hours, days, or weeks later. Cheap bulk black tea can be used, as can fresh oak leaves and acorns, or fresh willow bark and leaves. You can take them off the ground but rain will leach the tannin out, so it's just easier to cut it from the tree and get a good concentration for your work. Quebracho bark powder is available elsewhere in the world for cheap, if you can find some - should be something like $20 for 5kg. Results in a red-brown adobe brick color which I'm not super happy with, but it's easy.

Only major thing that working small animals won't teach you is that thick skins need time for solution to penetrate, and that with bark tanning using too-strong a solution initially can cause the skin to "case-harden" and block further tan from going deeper, leading to rot. For thick bark tanned skins you need to start with a pre-used tan to allow it to penetrate without sealing the skin from further tanning. You then beginning increasing the solution concentration as the skin uses up the tan.

Probably a few typos and mistakes in there, but that's the main stuff that people seem to get blindsided by.

Thanks Canross. I'm thinking of making some knife sheaths. I've tried vegetable tanning just once. I soaked a possum skin in a wattle bark solution. It went a deep reddish colour. Best wishes.....