Posts tagged #tanning skins

The Worst, Common Bark Tanning Mistake

On the road from raw skin to leather, there are many potential mishaps. Skins and plant liquors are potential food for bacteria, yeasts and fungus and growing the wrong ones, or too many, or for too long, can damage or blemish a hide. When dealing with natural materials, we typically have a sizeable degree of variability to contend with. It is very likely that home tanners are dealing with materials and quantities they aren’t familiar with.

One cluster of mistakes that all lead to similar results or scenarios stands out as the worst common error. Put most simply it is, that the hide is left for too long, in solutions that are too weak. This can come about in various ways and have differing effects, but it is super common. In this video, I lay out the typical scenarios and try to offer an approach to prevent them. This is an important video for anyone starting out in bark tanning, because this general area of understanding is so often lacking in the beginning. Nearly everyone seems to make these same mistakes, I know I did, and they need to be headed off intentionally.

Because there are so many variables in natural tanning, it is impossible to accurately quantify all of this. I can’t give out step by step instructions with times and quantities. It just doesn’t work very well that way with all the variables involved, not the least of which is tannin content by species, individual trees and condition of materials. What I can give is a general approach to this problem that will allow you to adapt to new materials and unknowns. That essentially involves observation and understanding the typical way things go as far as the hide tanning rapidly at first, then requiring a high enough level of tannin in the liquor to preserve the skin as it finishes tanning. Also, that some color in the liquor is not necessarily indicative that is has any tanning power left. There is a measuring device called a barkometer, but I don’t own one and find that I can judge when to add tannin by observing the liquor and behavior of the skin. Bullet points are…

*Always look at the liquor, before, after and during, just always; any time you add liquor or check the skin, or have a new batch of liquor. Pick it up in your hand and look at the color and density. All materials are different in color and how much tannin v.s. other coloring matter they contain, so you are making comparisons mostly with fresh, v.s. used and partially used samples of whatever you happen to be working with.

This fresh, strong bark liquor has a bright look and high color density

This fresh, strong bark liquor has a bright look and high color density

This solution, while retaining some color, has no tanning power left, or not enough to matter.  It will grow bacterial scum on top and the hide will decay slowly, because it is just starting to tan.  All color is not indicative of effective tannin.  With a wll prepared skin in new starter solutions, this phenomenon can happen in one day.  Unless you add a lot of tannin quickly, (which is sometimes okay) it will keep happening, but eventually it will slow way down and the solution can be left for long periods of time unattended.

This solution, while retaining some color, has no tanning power left, or not enough to matter. It will grow bacterial scum on top and the hide will decay slowly, because it is just starting to tan. All color is not indicative of effective tannin. With a wll prepared skin in new starter solutions, this phenomenon can happen in one day. Unless you add a lot of tannin quickly, (which is sometimes okay) it will keep happening, but eventually it will slow way down and the solution can be left for long periods of time unattended.

*Understand that in the beginning, hides typically take up tannin very fast.

*If the skin is left for any length of time, the liquor needs to have enough excess tannin to adequately preserve it, and also to insure that tanning continues to progress.

*Be prepared to gather/prepare/add more tanning material as needed. Thoughts such as you used a “lot” or it “should” be enough are not really relevant. It’s either doing the job, or you need more. Sometimes that is a lot if the materials are not very rich in tannin, or it is something that is just hard to gather in enough mass.

*A healthy tan can smell quite strong and in a way unpleasant. I would characterize it as unpleasant, but kind of intriguing and not just flat out disgusting or vile. It is an odd smell that will cling to your skin for a time after touching it. While an element is unpleasant, there should also be a large measure of fermentation to the smell. All of that is normal. It shouldn’t just smell putrid or flat out offensive in the way that rotten food, a dead animal or an outhouse does. Some growth of stuff on the surface can be normal.

*Typically, tanning will progress very rapidly at first, then slow down a lot as the core of the hide slowly tans. Keep the solution rising in strength if anything during this initial phase, then leave it strong enough to maintain a healthy tan as it finishes. Common ways to fail at this objective are: Using low tannin materials, not using enough material, putting the hide in and leaving it without strengthening the tan, Judging by how much it seems like you’ve used instead of by how tanning is progressing (or not), and what the liquor is doing.

*A fairly reliable approach is to cook the material twice. Use the second cook liquor to start the hide, with some water add as necessary to cover the skin well. observe the liquor before putting the hide in. Add the stronger first cook liquor over the several days as you see the liquor depleting and the hide tanning. If you run out and it still seems to be drawing down the liquor, make more. I also talk in the video about dumping some of the liquor to bring the water level down and the tannin level up to get a solution you can leave the skin in. When it is no longer rapidly depleting, you can get the strength up and attend it less frequently. This approach gets most of the tannin out of the material, prevents any possibility of tanning the skin too rapidly in the beginning, is continually adaptable, and encourages familiarity with our materials and their tanning potential.

That is the quicky version, but it should be enough to avoid this worst common problem in bark tanning.

I’ll link two video playlists here. One is a lot of useful general tanning videos and the other is my strops from scratch series, which follows the tanning of a deer skin with oak bark.

Vegetable Tanning Materials, Tannin Rich Barks, Roots and Leaves Used to Tan Skins and Hides Into Leather

I am asked a lot about what tanning materials people should use in their part of the world. Well, be careful what you ask for he he. Here is a very large amount of information to address fill that gap. I had already typed up a partial list for a vegetable tanning book project that I have done some writing on which is mostly presented here (don’t hold your breath on me publishing it anytime soon). That information comes largely from Howe’s book on tanning materials, which I think is still in copyright. But I decided to list a bunch of full text excerpts on tanning materials from some other old out of copyright tanning books. To top it off, at the end there is a surprisingly long bibliography of publications on tanning materials put out by the USDA, with such fun topics as tannin content of some acorns, Tannin content of pacific coast trees, tanning materials in South Africa and the tanning industry of Washington state. There is still much more that could be dug up on the subject. If you want to research a specific material more, you can use sites like googlebooks.com and Archive.org Try different combinations of keywords such and as leather, tanning, tannin, the plant’s common names and the plants botanic name (or names, plural since they often change over the course of 100 years or more in order to keep botanists employed and make them look busy).

Tools You Need to Bark Tan Hides & Skins Into Leather at Home; Traditional Vegetable Tanning

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In this blog post and new video, I cover all the essential tools needed to make good bark tanned leather as well as a few non-essentials. Tanning materials will have to be treated separately and I will try to revisit many of these tools and their making in the future.

Real natural vegetable tanned leather is that which is tanned with tannic acid sourced from plant materials. While there are excellent sources of tannin in not just barks, but in roots, leaves, pods, fruits, nuts and wood, tree barks are the most used sources, thus the common term bark tanning. There are only a few tools and materials that could be considered essential to the process and none are complicated. In fact, if you strip it down to the real essentials, you need very little. Adding a few simple tools will improve your experience though, and in some cases your leather.

Some tools of the Tanner and Currier, most of which are discussed in this article. The slate bladed two handled knife B is especially intriguing. I need to make me one of them.

Some tools of the Tanner and Currier, most of which are discussed in this article. The slate bladed two handled knife B is especially intriguing. I need to make me one of them.


FLESHING KNIFE

The tanner’s knife, or fleshing knife, is the most important multi-tasking tool of the tanner. In a typical vegetable tanning process, I will use this tool for fleshing, dehairing, re-fleshing, scudding, removing excess water and stretching open the skin. It is also handy when re-soaking dried hides to work open dry spots so that they rehydrate faster. Many new models are available on the market, but a lot of home tanners get by well with homemade tools. Read my blog post on fleshing knives, and watch the Fleshing Knives 101 video for more than you probably wanted to know about them. I just received the Wiebe 12” Fleshing knife in the Mail so I can review it for you guys. I like the overall form a lot for general use, and was told by a dealer that it is actually tempered tool steel, not mild steel. Aside from the potentially weak, narrow and probably short tangs, it looks promising, but I haven’t had a chance to use it at all yet. Aside from unknown potential steel/tempering issues and iffy tangs, as a general purpose home tanning knife it seems likely to be a good choice for under 30.00 shipped.

A collection of tanner’s knives

A collection of tanner’s knives


BEAMS

Wood and plastic beams. Left is the outside cur from a log mill and the other is cheap ABS, though PVC would be much better, thicker, more durable and heavier. I haven’t used plastic beams much, but I can see why people might need to use them.

Wood and plastic beams. Left is the outside cur from a log mill and the other is cheap ABS, though PVC would be much better, thicker, more durable and heavier. I haven’t used plastic beams much, but I can see why people might need to use them.

The tanners all purpose scrapping knife is of no use without a beam. For most, a beam around 6 to 6.5 feet long will do well. I’m currently using. 6.25 foot beam, which is just about right for me. It can be of wood or plastic pipe. If wood, it is best to have a smooth work area that is free of knots, large cracks, grain tears or other major blemishes extending at least 18 inches down from the top. I would try to stick with 8” diameter and larger, but to get started, or in emergencies, you can use a smaller diameter beam. If the diameter is very small, you can flatten off the working area to a larger radius. A very small radius results in a small area of contact between the tool and the beam surface. For most vegetable tanning related beam tasks, a larger surface contact between beam and tool is preferable. Large logs should be at least split in half, or even hollowed on the underside to thin them. Most of my old beams were hollowed out on the underside with a hatchet to reduce weight and discourage cracking. Taking the center of the log out by splitting it in half will reduce both the incidence and severity of cracking. Reducing the thickness further will reduce that risk even more. It doesn’t have to look pretty, just chop out some of the wood to form a hollow on the underside.

A good source of nearly ready made beam material are the round sided slab cuts from the outsides of logs removed in milling lumber. You may be able to get some from a local mill, or small custom miller. Check the phone book (under lumber, milling?) or ask about local portable mill owners at your chainsaw dealer or repair shop.

If making a beam out of lumber, choose vertical grain like this over plain sawn face grain if possible as it will be less likely to crack. This is never a choice with a round or split log.

If making a beam out of lumber, choose vertical grain like this over plain sawn face grain if possible as it will be less likely to crack. This is never a choice with a round or split log.

I haven’t done it, but I suspect a pretty good beam could be made by radiusing the working area of a 2x12. I don’t seen any good reason it wouldn’t work. If so, try to choose one that has edge grain on the working face and not face grain. that is to say that the rings of the tree run from about 45 degrees or more toward straight through the thickness of the board. This is usually referred to as vertical grain and will be much less prone to cracking than plain sawn wood faces.

Now that I’m thinking about it, an edge grain (if you can find that good of a board these days) 2x12, backed by another 2x12 could make a pretty nice beam. I would leave a slot in the backing board for a plywood stand, augmented by two 4x4’s firmly attached with lagbolts similar to the arrangement pictured below. For a firmer union, wedges could be used to afix the plywood in the slot.

You can do many different things to put legs on the beam. A good option is to drill large holes, about 2 inches in diameter and plug in round wooden staves for supports. My current beam has two closely spaced boards screwed to the bottom on edge, just far enough apart to slide in a piece of plywood as a support. It works well enough.

Simple support that is easily taken down for transport. I would use 4x4’s next time.

Simple support that is easily taken down for transport. I would use 4x4’s next time.

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DRAW KNIFE AND SPOKE SHAVE

Maintenance tools. The drawknife is probably more versatile and essential than the spokeshave.

Maintenance tools. The drawknife is probably more versatile and essential than the spokeshave.

These tools are used for creating and maintaining, a smooth beam surface. It is ideal to have both. The draw knife is best for major wood removal and repair, and the spoke shave for maintenance and smoothing. You can get away with just one of them though, in which case the draw knife is the more versatile of the two. Draw knives are also handy for peeling tan bark from logs if it is not slipping off easily. If you intentionally shred the bark off of the log in small, thin slices, you may not have to chop it any finer for extracting the tannins.

When shopping for used draw knives watch out for two things, wear on the blade and rounded bevels on the back side. Old draw knives can sometimes suffer severe wear. Look to see that the blade is about the same width it’s whole length. It should also be flat on the back with a bevel on the top side only. Either by long wear, or by mis-sharpening, the back is sometimes not flat. In a very well used knife the back may be subtly dished or rounded off, but if it has an obvious bevel or extreme wear, steer clear.

I would not recommend buying a spoke shave that has only one screw to adjust and no fine adjustment screws. The type shown is common and works well.


WATER AND HOSES

Water is not just a material, it’s a tool for cleaning things off. Skins, tools, boots, hands and tubs need frequent rinsing You will use a lot of water, and the more convenient and available it is the better. I usually use a standard hose end shut off valve to control flow. I like these valves better than most purpose made sprayers, because when opened wide the flow is fairly high, which is nice when you are filling containers with water a lot. If opened only part way, the shut off valve makes a reasonable sprayer for cleaning things off. As far as I have seen, craftsman rubber hoses are the best deal going when they are on sale in the spring, which they usually are.

Better than any sprayer I’ve tried when you want high flow.

Better than any sprayer I’ve tried when you want high flow.

Passable spray pattern and volume if not as good as a purpose made sprayer.

Passable spray pattern and volume if not as good as a purpose made sprayer.


BRUSHES

A stiff cleaning brush will be found almost indispensable for tubs, aprons, beams and tools. You may also need a finer brush to scrub bloom off of the grain side of skins. Bloom is a whitish deposit that forms on the grain surface during tanning. It is more common with certain tanning materials and also when layering or pit tanning is used.

Stiff brushes for cleaning tubs, tools and beams are almost essential

Stiff brushes for cleaning tubs, tools and beams are almost essential

Surface on the right shows bloom deposited in the tanning process. The section on the left has been scrubbed clean with an old hair brush with medium bristles. The dark stain in the center is where the skin floated above the surface of the tan liquor :-/

Surface on the right shows bloom deposited in the tanning process. The section on the left has been scrubbed clean with an old hair brush with medium bristles. The dark stain in the center is where the skin floated above the surface of the tan liquor :-/


PROTECTIVE CLOTHING

BOOTS: Rubber boots are very nice to have if you do a lot of tanning. If you don’t wear them, the hide will inevitably drip all over your feet as you stand at the beam working.

GLOVES: I tanned without gloves for years, but I love my elbow gloves now. Don’t bother with dishwashing gloves, or any other short gloves. You will inevitably reach into a solution and they will fill with smelly liquid. I use these affordable Atlas gloves, which have held up okay. When they die, I may invest in a more heavy duty glove.

APRON: I would avoid buying very cheap aprons. I am still using the same two heavy duty black, rubberized cloth aprons that I bought used at a yard sale over 20 years ago. You can make one from a sheet of vinyl or plastic of some kind, or tie a trash bag around your waist, but if you tan a lot, the protective gear is really nice to have. Hip waders are great if you already own them.

Non-Essentials, but so nice to have!

Non-Essentials, but so nice to have!


CONTAINERS

Vegetable tanning requires certain kinds of containers. Materials that can be safely used for all the processes are wood, plastic and rubber, ceramic, stainless steel and enamel ware. I use galvanized tubs, but only if there is no rust at all on them, and for liming and rinsing only. Aluminum I’ve used for rinsing only. I know aluminum and ashes don’t mix well but I don’t know about lime. While I have no idea if aluminum is safe for tanning liquors, I’ve avoided it. Anything that rusts is out of the question for all processes related to vegetable tanning except for dyeing the skin black. Any rust or iron will darken the skin permanently.

The common rectangular plastic storage tubs with lids are the most versatile. Choose designs that can be rained on without funneling any water into the tub if possible. Some do not have that kind of overhang on the lids, or have holes of some kind on the edges. All of these others also get used, but none are particularly better than rectangular tubs.

The common rectangular plastic storage tubs with lids are the most versatile. Choose designs that can be rained on without funneling any water into the tub if possible. Some do not have that kind of overhang on the lids, or have holes of some kind on the edges. All of these others also get used, but none are particularly better than rectangular tubs.

The ubiquitous 5 gallon plastic buckets are handy to have around for various uses, but tanning anything over the size fur bearers in buckets is unpreferable. Large rectangular plastic storage tubs of 15 gallons and up are very useful as are other large tubs of various sorts. I have used wooden wine barrels cut in half quite a lot. They look really great, but aesthetics aside, they have their down sides. Wooden barrels need to be kept filled with water, or they dry out and fall apart. Since they need to be full of water, they breed mosquitoes unless you dump them regularly and they are quite heavy when full. You can tan hides up to the size of deer in half wine barrels very easily and sometimes large hides if you get creative. The size of the container should be adequate for the size of skins you are tanning. Without getting into specific details, an 18 to 20 gallon tub is adequate for deer, goat and similar sized animal skins. I’ll usually cut cattle and other large hides into sides and bellies, and those pieces can be tanned in a half wine barrel or large rectangular tub easily enough.

Rectangular tubs are an advantage over round ones, when layering, a technique where you put layers of shredded bark between layers of hide and let it sit for a month or three. I can layer a deer hide well in an 18 or 20 gallon tub, by carefully folding it up with layers of bark between all the folds, but if layering a larger hide, or even a very large deer skin, you’ll need to size the tub up. For liming, rinsing, or tanning the skins in liquors, round containers have the slight advantage in being easy to stir, but that is not important enough to favor buying them over the more versatile rectangular tubs. Use what you have or can get cheap or free if it works, but if you buy something storage tubs with lids are probably the best all around. If you are tanning cattle, elk, moose, horse or buffalo skins, and want to keep them whole (not a very good idea unless you really need it that big), start keeping your eye peeled for larger containers. However, too large is too large. You don’t want to have to use excess amounts of liquid to tan, rinse or lime a hide.


BARK CHOPPING

Primitive and slow, but effective enough. The benefits are that it makes you slow down and chill out, and it’s good hatchet practice.

Primitive and slow, but effective enough. The benefits are that it makes you slow down and chill out, and it’s good hatchet practice.

Some materials, like sumac leaves are easy to use, but you will generally have to cut up barks, roots and woods. I have almost always used a hatchet on a block of wood. I lay out a tarp to catch the chips and start hacking away. You could use a small axe, but for most people, an average sized hatchet is a good weight to start with. A heavy hatchet or axe can lead to repetitive strain injuries like carpal tunnel much faster. Just ask my tendons about that.

Hatchets can also be used to “raze” off the outer dead portion of the bark, which was sometimes so removed in traditional tanning as it was considered unnecessary or even injurious to the leather.

Chipper/shredder machines can be very effective. Garden chippers are often under-powered for thick heavy bark, but they are nice when they work. If necessary, you can break the material up into smaller pieces, or try shredding it while still fresh and softer. If there is a lot of rust in the chipper, it could contaminate and darken your liquor. Consider running some branches and leaves through the unit to clean it out.


COOKING POTS

It is possible to extract the tanning materials from plants with cold leaching, but it is much faster to cook it out. Even though I don’t know that it isn’t safe, I have always avoided aluminum. That is easy for me to do though, because I have large stainless steel pots from 3 to 5 gallons. Enamel pots could work, but be sure there are no rusty spots where the enamel has chipped away. Copper was used at one time, but large copper containers are expensive and uncommon. Large thin walled stock pots with thin bottoms can be very cheap and are fine for cooking bark, but will easily burn food if you are not careful. Try to get at least 16 quart and preferably 20 quart or larger. I find large stock pots like this to be indispensable tools in my lifestyle and they are a lifetime investment. When shopping key points to look at are thickness, build quality (especially handles) and steel quality. Some stainless imports are made of inferior metal. Read reviews carefully. When I won some fancy all clad cookware in a contest, I sold it on ebay and bought a Tramontina stock pot, which I’m happy with.

A 3 gallon stainless stock pot. Get 20 quarts or larger if you can afford it or better, repurpose a stainless beer keg.

A 3 gallon stainless stock pot. Get 20 quarts or larger if you can afford it or better, repurpose a stainless beer keg.

You can also modify an old beer keg, which many home brewers do for cooking beer mash. Full sized Kegs are 15.5 gallons and a 1/4 keg is 7.5 gallons.

I also own a large pool filter housing that must hold around 25 to 30 gallons. I set it up with a valve and cook large batches of canning jars and bark in it. I have never seen a comparable one. In most units the lid is nearly as tall as the body, making them of limited use.

My pool filter housing bark boiler, aka the MEGA CANNER.

My pool filter housing bark boiler, aka the MEGA CANNER.


Happiness is tan liquor on tap. It doesn’t get any better than this folks.

Happiness is tan liquor on tap. It doesn’t get any better than this folks.

SLICKING TABLE OR BOARD

To use the following two tools, the slicking iron and slicker, you need a large flat surface of some kind. The skin is stretched, smoothed and flattened with this trio. These are only used if you want to dry the skin smooth and flat. If the hide is to be softened you dry it in some way that is less involved. A good technique for drying hides flat is to paste them down to the board with fat applied to the flesh side. This technique allows us to finish the grain out perfectly smooth and then leave it on the board to dry slowly. Just put it where your chickens can’t walk on it! You can also nail the skin to a wall to stretch it, or lace it into a frame, but for leaving hides well flattened and finished, you probably can’t beat the slicker and slicking Iron on a smooth slab. If you are doing thick skins, you can get away with something that has a rough surface, such as unfinished plywood. When working thin skins on a slab, the surface should be smooth or the texture of the surface will show through on the grain, much like the technique of rubbing a piece of paper placed over a textured surface with pencil or charcoal. I use plywood and a large slab of thick salvage plastic. Traditionally, stone tables have been used. If you run across a large surface that is very smooth, water resistant and 4 feet or more wide, grab it.

A large sheet of salvaged structural plastic that I use as a slicking board.

A large sheet of salvaged structural plastic that I use as a slicking board.

Cattle leather oiled and pasted out to boards to dry with the slicker. When working with thick skins, the board texture will not show through. When finishing thin skins, you will need a smooth surface unless the skin is to be softened later, or the wood grain will show through on the hide’s grain surface.

Cattle leather oiled and pasted out to boards to dry with the slicker. When working with thick skins, the board texture will not show through. When finishing thin skins, you will need a smooth surface unless the skin is to be softened later, or the wood grain will show through on the hide’s grain surface.

The skin can be pasted to the board with a coating of fat on the flesh side. It will stick well enough if it is dried slowly. When pasting thick skins to boards, you must use wood for thick skins or the skin may mold from drying too slow. For thin skins you can get away with pasting them to a non breathable surface like plastic, but make sure they still dry out within a couple of days. I use this technique a lot. I also often use it if I’m going to use the graining board to soften the skin (see below), but in that case, it is okay to use a rough piece of plywood, because the grain is going to be wrinkled and reworked anyway so the texture of the board showing through the skin is of no consequence.


SLICKER

This tool is usually made of stone or glass and you can make your own with a piece of slate. it is a slab of hard material, with one rounded smooth edge, and and smooth rounded corners. A handle is nice, but not necessary. The tool is used to smooth and even the grain side of the skin and to paste it down onto a slicking table or board with fat for slow drying. You could probably have a glass shop make you one out of a 3/8” glass. A shop that works with stone tiles should be able to make you one as well, or at least cut a slab for you if they don’t already have some spare tiles of the right size. If you want to make one, cut a piece of slate or other clean hard stone and grind the edge round on a slab of cement or sand stone. Use water as a lubricant. If the stone is hard, add sand with water to make a slurry. Slate is fairly soft and easy to work. This method will even work with hard stone or glass if you are patient. It can be finished and polished with diamond sharpening hones and/or sand paper. A belt grinder would also be very handy, but the dust will mess up your lungs. Silicosis fibrosis anyone? Glass grinders are lubricated with water to prevent dust. You can also still buy slickers new, since a few leather workers use them for polishing. I have also used hardwood and moose antler in a pinch.

Size should be around 4x5 inches and 1/4 inch or more thick, with the long edge being the rounded working edge.

Vintage slickers from the museum area of the Muir McDonald Tannery in Dallas Oregon, now sadly closed. Both are slate. In the tool on the left, it appears that there may be screws for clamping the slate into the handle.

Vintage slickers from the museum area of the Muir McDonald Tannery in Dallas Oregon, now sadly closed. Both are slate. In the tool on the left, it appears that there may be screws for clamping the slate into the handle.

Glass plate in a leather working machine. This partly replaced and augmented the slicker. This may be the scariest machine I’ve ever seen in operation. Muir McDonald Tannery, used to polish the grain of tooling leather.

Glass plate in a leather working machine. This partly replaced and augmented the slicker. This may be the scariest machine I’ve ever seen in operation. Muir McDonald Tannery, used to polish the grain of tooling leather.

Smoothing the grain and flattening.

Smoothing the grain and flattening.

Home made slate slicker 1/4 inch thick and a slab of repurposed jade with the edges polished

Home made slate slicker 1/4 inch thick and a slab of repurposed jade with the edges polished

ideal slicker edge is evenly radiused and polished.

ideal slicker edge is evenly radiused and polished.

The slicker at work dealing with wrinkly edges. This tool is always used with fat as a lubricant.

The slicker at work dealing with wrinkly edges. This tool is always used with fat as a lubricant.


SLICKING IRON

My current ideal slicking iron prototype. I would favor a thick blade. This is a tool where weight and rigidity can be advantageous.

My current ideal slicking iron prototype. I would favor a thick blade. This is a tool where weight and rigidity can be advantageous.

This tool is similar to the slicker in size and shape, but it is a metal scraper with a dull edge. It is used on the flesh side of the skin to even out wrinkles and smooth and stretch the skin out toward the edges, before turning it over to use the stone or glass slicker. The slicking iron should not be super wide, about 5 inches wide at most. If I made one to my specifications right now, it would as in the diagram. It would have a very, slight radius across the working edge. I would also add a generously sized hardwood handle that is slightly drop shaped in cross section, copper riveted, and saturated in raw linseed oil. Regular carbon steel is okay to use, but always check it for rust and clean before using. Never leave it resting on the skin.

A serviceable homemade sicking iron and a cheap dough scraper. The dough scraper is on the thin side, is already rusting and should be modified to narrow it. It is probably better to check in with local scrap yards, metal fabricators and sheet metal workers.

A serviceable homemade sicking iron and a cheap dough scraper. The dough scraper is on the thin side, is already rusting and should be modified to narrow it. It is probably better to check in with local scrap yards, metal fabricators and sheet metal workers.

Dough scrapers can be used if modified. Most dough scrapers are wide and could stand to have an inch or more removed from their width to make them 4.5 to 5 inches wide, which you can do with a hacksaw and files. Use a file to sharpen and modify. The corners should be rounded off well to a 1/4 inch radius and the whole thing sharpened from both sides to form a fairly obtuse edge (not too thin) and then dulled enough that it won’t cut the skin. The edge should be of such a dullness that it will easily grab the skin and pull it when the tool is used, but will not cut or gouge it. If shopping for one, look at reviews to make sure it is not too thin. Cheap scrapers will bend under the high stress applied to this tool under normal use. I bought this one and it is barely thick enough. It is also already showing some rust as cheap stainless steel is prone to do. Here are a few that look like they may be thick enough, but it’s hard to say until you see them in person. pizza cutter, RSVP, OXO. Keep in mind that they will still be better if modified by narrowing them, so dropping by your local sheet metal worker or metal fab shop first is probably smarter. They usually have lots of scrap around and all the tools to make something like this quickly, minus the handle. If you have a file, a drill and a saw to cut a kerf in a wooden handle, just have them cut out a slab for you and do the rest yourself. If you have a good metal salvage yard around, look there for scrap stainless.

This paunchy spot was eventually flattened completely by persistent work with the slicking iron and slicker.

This paunchy spot was eventually flattened completely by persistent work with the slicking iron and slicker.

You may very well be able to use some sort of household item or kitchen tool in place of the slicking iron, for instance a thick stainless spatula. You can also do some of this work on the beam with the fleshing knife, like stretching the skin our toward the edges. At times though you may wish you had the slicking iron for dealing with tough wrinkles and lumps in heavy hides. I would definitely say it is more necessary and useful when dealing with big thick skins. It’s not a tool you have to have to start tanning. You will know when you need it. Checkout this image of Talcon working down a paunchy spot in a bark tanned bull hide. That spot ended up totally flat in the end. This is the kind of application where the slicking iron shines.

The same hide flattened, smoothed, pasted with fat to the board and left to dry slowly.

The same hide flattened, smoothed, pasted with fat to the board and left to dry slowly.


OTHER OPTIONS FOR STRETCHING AND DRYING

If you do not have a slicking table, and need to stretch a skin out to dry, you can use a frame with ropes. Cut many holes, parallel to the edge and lace the skin evenly and tightly. This will not always remove wrinkles and paunchy spots like slicking out on a flat surface can. Framing a hide is also a lot of work and wastes skin around the edges. Similarly, you can stake the skin out flat just off the ground. A better option than both for most people will be to nail the skin out to a large board or wall. Use hot dipped galvanized box nails if you can. Any nail that will rust is not recommended and nails that are already rusty are a sure way to leave black stains on your hide.

Horse sides framed for drying. Not the best solution in terms of labor and material conservation. It also does not provide the best options for flattening and smoothing the skin.

Horse sides framed for drying. Not the best solution in terms of labor and material conservation. It also does not provide the best options for flattening and smoothing the skin.


PALM AND ARM BOARDS

Old engraving of a Currier at work with an arm board. If you look closely, you can see that the artist illustrated the wooden teeth on the sole of the board

Old engraving of a Currier at work with an arm board. If you look closely, you can see that the artist illustrated the wooden teeth on the sole of the board

Skins can be softened by rolling on a table with the hands and forearms. These tools are used to make that job easier and work the skin a lot harder.

The soles are designed to grip the skin’s surface. One type has a wooden face with ridges carved into the sole from side to side for when the tool rides on the flesh side of the leather. Boards with cork glued to the soles are used when the tool will contact the grain side.

There are two basic sizes, a hand board, sometimes called a pommel, and an arm board. The hand board is short, 8” or less, with a strap that goes over the hand. The arm board rests along the forearm and has a strap at the back and a peg at the front for a handle. The difference is size and scope of work. Any home tanner ought to do fine with hand boards.

If the skin is worked folded grain side to grain side, the result is a pleasing wrinkled grain surface since the grain is crushed and compressed. The process of creating that grain effect is called graining, thus the term graining board. In this case, the sole of the tool touches the flesh side only and the teeth cut into the wood provide excellent grip.

Postion for graining process. Note the ridged graining board contacts the flesh side only.

Postion for graining process. Note the ridged graining board contacts the flesh side only.

Surface produced by graining

Surface produced by graining

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If a board is used with the skin folded flesh side to flesh side, the grain surface is left smooth because it is stretched instead of compressed. The cork soled board is used in this case to prevent denting and damage to the grain surface.

An antique cork faced arm board from the Muir McDonald Tannery in Dallas Oregon. Note that the cork is partially worn off on the front of the tool

An antique cork faced arm board from the Muir McDonald Tannery in Dallas Oregon. Note that the cork is partially worn off on the front of the tool

Fancy Antique cork soled board.

Fancy Antique cork soled board.


MALLET

In some cases, we may want the skin to be compressed and hardened, not softened and broken loose. The tool for this is a wooden mallet with a polished face, which is used to condense the leather when it’s in a damp, but not wet state. The face can be close to flat, but the edges have to taper off and round out gently. If you are leaving any kind of dents in the skin, then you need to either hit the leather flatter, or refine the edges. The leather should be smooth when finished. Use the heaviest wood you can, mine is probably iron wood and is extremely dense. Polish the face to a gloss finish. In the past, both Iron and brass/bronze mallets have been used, but make sure they are very clean and polished, with zero rust or oxidation. Even so, you are risking staining the skin with a steel hammer, so I recommend sticking with wood.

The mallet for compressing and firming leather should be dead smooth. Use the densest wood available. The hide underneath in the foreground has been pounded leaving it about 1/3 thinner, much denser, stiffer and polished. Otherwise, it was exactly the same as the top piece.

The mallet for compressing and firming leather should be dead smooth. Use the densest wood available. The hide underneath in the foreground has been pounded leaving it about 1/3 thinner, much denser, stiffer and polished. Otherwise, it was exactly the same as the top piece.


STAKE

This is a dull metal blade set into a post that is used for softening and breaking open the fiber of skins. They are useful if you are trying to get skins really soft and for working furs. Unless you are doing one of those two things, it’s not a very essential tool. I find them more useful in braintanning buckskin and working furs of any kind. The post can be permanent or in a stand of some kind for portability. The blade should be rounded at the corners and they usually have at least a very slight radius. The width of the blade can vary. For any kind of large skins, a wider blade would be better. 5.5 inches with the edges rounded to a 1/4 inch radius and a very, very slight radius to the whole edge would be good for general home tanning work of all kinds. A lot of dough scrapers are 6 inches wide, so that might be a good source of material for a blade. It should be stainless if possible, so you can leave it wet or in the weather. Use stainless steel screws as well.

A simple portable stake used for classes. A fixed stake or one on a heavy base is better if you’re going to use it a lot.

A simple portable stake used for classes. A fixed stake or one on a heavy base is better if you’re going to use it a lot.

Use stainless steel screws

Use stainless steel screws

A good stake blade design for the home tanner.

A good stake blade design for the home tanner.

This blog post and similar content is informed by almost 30 years of research, experience and communication with other tanners. You can support my efforts to bring back and preserve these traditional self reliance skills and arts by sharing content to friends, forums and social media, with general financial support on patreon.com/skillcult, or with one time donations using the link in the side bar. I also now keep separate accounts for earmarked donations toward research in tanning and apple/plant breeding. If specified, donated funds will be used for things like tools and materials, and outside labor solely related to either endeavor. Thanks for reading :)

A Review of Tanning, Leatherworking and Skin Related Books in My Collection

Below are Tanning and skin working related books collected by myself and Tamara Wilder over the years.  The video version talks about these books and a little history and such.  Some of them are broadly recommended, and some are only for people with certain specific interests.

Many, many books on Tanning, Glue Making and Leather working that are not listed here are available as free downloads from the Downloads page, SkillCult.com/freestuff

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Buckskin, The Ancient Art of braintanning, Steven Edholm and Tamara Wilder, 1997: 

The book I wrote with Tamara Wilder in 1997.  From what I've seen, it is probably the longest and most detailed book on home tanning to date, especially considering it's focus.  As of writing this, it is currently out of print with plans to revise and re-print in digital and print forms.  Covers wetscrape braintanning, with some satellite subjects like sharpening and dyeing buckskin with natural materials.  If you've read it, please consider leaving a review on Amazon.


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Deerskins Into Buckskins, Matt Richards, 1997: 

Published the same year as our book, this one also covers the wetscrape method, but focused on bucking, which is using alkali to soak the hide instead of water.  It is the best, if not only, book reference for that technique.  There is also a companion DVD.


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Traditional Tanning Leather and Furskin, Lotta Rahme, 2014:

This would probably be my number one recommendation of a book on general tanning covering a lot of ground and many methods.  It has lots of anecdotes and tidbits on traditional tanning from various parts of the world, and good basic information on tanning chemistry and theory.  If a person were interested in braintanning primarily, they should get a book on that subject.  This may be currently the best single book reference for vegetable (bark) tanning.  Lotta is an experienced, small production tanner, with her own micro-tannery, so she has real insight, skill and knowledge to offer.


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Fish Leather Tanning and Sewing, Lotta Rahme, 2006: 

Lotta's cool book on tanning fish skins.  This is a popular subject.  I keep hearing about and seeing more and more fish leather. Much of the information is also contained in her general leather tanning book, but there is also a lot of information specific to fish skin and various species of fish, though they seem largely to be species from her part of the world, Sweden.


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Blue Mountain Buckskin, Jim Riggs: 

My teacher and teacher of my teacher Jim Riggs.  Jim was largely responsible for disseminating braintanning knowledge, having learned from his teacher Buckskin Slim Scheafer, who's book is below.  This is the best all around reference on dry scrape braintanning.  Fun, thorough and insightful.  #1 recommendation for a book on dry scrape braintanning.

Jim died last year.  He was friend and mentor many and had a profound and enduring effect on the primitive skills movement.  Many people's live took radically different directions because of either contact with Jim, or with others infected with his knowledge and philosophy.  My buckskin book contains much of Jim and would not exist without him.  Blue Mountain Buckskin is an enduring slice of Jim in the best way.

Tribute page for Jim Riggs: https://www.facebook.com/pg/jimriggsmemories/community/


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The Tanning Spirit video, Melvin Beatty, click here to watch:

Mel is one of the best tanners I know to this day and has always produced the best quality wetscrape buckskin.  His tips helped me get to producing better wetscrape buckskin.  You can watch his video on the subject on youtube now.

Also visit mel at the following.  He posts tips and experience on braintanning at his facebook page.

www.Braintanbuckskin.com

And Facebook as BraintanBuckskin


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The Indian Art of Tanning Buckskin
"Buckskin Slim" Schaefer, 1973

Jim Rigg's teacher Slim wrote this book at Jim's urging.  It was published the same year as Larry Belitz' book, Brain Tanning the Sioux Way, those being the first two books specific to braintanning that I know of.  This book is out of print, but they show up on ebay and elsewhere now and again at not unreasonable prices.


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Brain Tanning the Sioux Way, Larry Belitz:

This is a small book and lacking somewhat in detail. There is enough information to learn the process, but it will be more trial and error than when using a more in depth book.  I think a lot of braintanners in the 70's and early 80's probably learned at least partly from this book.


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Making the Attikamek Snowshoe, Henri Vaillancourt:

Available on the Author's website, this book is fantastic.  It is exactly what it should be, a detailed documentation of a traditional art, with as much important detail as possible, recorded in quality images and insightful text.  Henri is part anthropologist and part craftsman, which is how it should be, but almost never is.  The section on hide working outlines interesting traditional methods common to moose country for tanning skins and producing rawhide, both very important skills in that part of the world.

 


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Home Tanning and Leather Making Guide, A.B. Farnham:

This guide has some useful information, but leaves something to be desired as a stand alone guide to tanning.  It is still one of the better references for vegetable tanning and well worth taking advantage of, all the more so, because it is out of copyright and can be download from tanning book collection


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Home manufacture of Furs and Skins, A.B. Farnham, no date: 

A useful book when it comes to handling and dressing furs.  Available as a free download from tanning book collection


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Home Tanning of Leather and Small Fur Skins, USDA, 1923:

Of limited use due to lack of detail, but worth reading.  Download from tanning book collection.

 


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Primitive Wilderness Living and Survival Skills, John and Gerry McPherson, 1993:

This book contains John McPherson's small book on braintanning by the dry scrape method.  It is a competent and useful guide to that subject, and also contains lots of other great stuff on primitive living skills of all kinds.  A good and useful book worth the price of admission from some old friends back in the day.

 


Aboriginal Skin Dressing in Western North America, Arden Ross King, 1938: 

This book is unobtanium, and likely only available in a few large university libraries.

 


The art of leather manufacture, Alexander Watt, 1885:

One of the better old books on tanning, although the only digital version I could find is the later 1906 version.  Available to download from the tanning book collection.  Much of the better part may be derived from the De LA LANDE translation below, which is more recommended.


The Art of Tanning and of Currying Leather... Collected From the French of monsieure De La Lande and others, 1773:

or download in my tanning book collection here

Maybe the best all around old resource I've found, introduced to me by friend and tanning colleague Jason Leininger.  Unusually well written and exhaustive for that time period.  Anyone who reads french should go to the original text, as no doubt things are changed, left out, or lost in translation.


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Dictionary of Leather-Working Tools, Circa 1700-1950 R.A. Salaman,1986:

Another book primarily for the enthusiast, tool maker and researcher.  A jillion variations on leather working tools as well as some tools of the tanner and currier.  Helpful in identifying old leather working and tanning tools.


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Secrets of Eskimo Skin Sewing, Edna Wilder, 1976:

Traditional patterns and techniques from the source.


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Glue, Gelatin, Isinglass, Cements and Pastes, Dawidowsky & Brannt, 1905: 

This is the book I learned most of what I know about glue making from.  It is a technical manual for manufacturers from the intersection of tradition and science at a time when hide glue was still king.  Dowload free from Glue Books Collection


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The American Indian Parfleche a Tradition of Abstract Painting, Gaylord Torrence, 1994:

An art book, packed full of art-speak.  There is some interesting history, and the small amount of functional detail it does contain helped me figure the process out eventually.  The photos are excellent.  This is a beautiful and unique practical art form that originally combined a functionality tailor fit to a singular lifestyle with expressive art.  Very neat book.

 

Axe Strops #6 Tanning the Deer Skin in Oak Bark

In this segment we finally begin tanning the skin.  Vegetable tanning is one of the neatest things I've ever learned.  This is the most exciting part where the hide fiber is transformed into leather.  Leather is not skin or tannic acid, it's a unique material made of the marriage of those two.  It can be left in the weather for years, and though it may become moldy and damaged it will not rot away for a very long time.  There are pieces in my compost piles that I pull out and throw back in every year just to see how long they will last.  The first piece of leather I tanned was a rotten piece of skin that I should have buried, but I had some oak bark sitting around so I made a solution and tossed it in.  The tan almost seemed to heal up rotten parts of the skin and knit them together.  I still have that piece of leather.  I left it hanging in a tree outside for a year or two once, but it appears pretty much unfazed.

Axe Strops #5, Rinsing, Drenching and Bark Preparation

In this segment we repeatedly rinse and scrape the skin to remove lime and unwanted gunk, then soak the skin in an acid drench made from fermented bran and water.  Oak bark is prepared by chopping and cooked to make the tanning solution.

The Most Common Bark Tanning Mistakes: Pitfalls to avoid on your way to beautiful leather!

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By Steven Edholm

Hey!, the Buckeye Gathering barktanning class is coming up and I have bark on the brain.  This article is going to be awesome.  A lot of people ask my advice on barktanning and I see the same mistakes made over and over again.  I can help, because I’ve made them all too (and still sometimes do), so I know whereof I speak!  So listen up fledgling barktanners, because we can save you a lot of frustration, heartbreak and WTF moments.

Procrastination:  This is a common mistake in tanning in general.  I still do it all the time, unfortunately, but I shouldn’t and you shouldn’t either.  Bark tanning is more forgiving than some other types of tanning because some of the solutions the hide is put into can be preservative to a degree, but that shouldn’t be used as an excuse to keep putting off what needs doing.  The solutions used in liming and tanning are not foolproof and will not preserve the skin indefinitely, so try not to use their limited preservative power as an excuse for procrastination.  good luck with that.

procrastination can lead to problems such as this damaged grain, which has lifted from the main body of the skin.
procrastination can lead to problems such as this damaged grain, which has lifted from the main body of the skin.

Using crappy hides:  For some reason, people tend to pick some crappy hide for bark tanning.  I don’t like to start any tanning project with a crappy hide.  It’s too much work to waste on something which can’t be better than the material which you are starting with in the first place.  If crappy hide is all you have and you want to experiment with bark tanning, working with just a small piece of it can be a great learning experience.  And in general, don't be afraid to "round out" scrappy skins, meaning trim off the rough stuff and tag ends, before tanning.  I also don't think it's a great idea to start with a really large hide.  Actually, squirrels are great and make a great starter project, and really nice leather.

This skin is scored.  Try to start with decent skins, or use parts of them to experiment on rather than tanning the whole thing.
This skin is scored. Try to start with decent skins, or use parts of them to experiment on rather than tanning the whole thing.

Leaving in the lime or buck too long:  Leaving the skin in lime or a bucking solution too long is not uncommon.  The skin can stay in for quite some time and come out Ok, but try to leave it in for a reason other than blatant procrastination!  This issue is dependent somewhat on the strength of the solution.  Although long liming is sometimes used intentionally, and sometimes in weak lime, generally you can process the skin as soon as the hair slips out easily.  Overly long liming can weaken the skin and damage the grain.

Failing to de-lime adequately:  Residual lime in the skin can cause brittleness and dark coloration.  Rinse the skin thoroughly many times, and scrape over it on both sides between soakings.  Re-scraping to push out lime and dissolved tissue is called scudding.  You can finish with bating or drenching (soaking in poop or fermenting bran respectively, but that's another story), or at least rinse with a splash of vinegar in water before tanning begins.

Using weak-ass material to make the solution:  It takes quite a bit of tannin to finish out a full skin from a medium sized animal, let alone something large like an elk or cattle skin.  There are tannins everywhere.  They are in most plants to some degree.  Finding sources rich enough, or abundant enough, to make good tanning solutions and finish your project is less common.  Don't use, old dead bark or dead leaves.  You need leaves or bark that have been gathered when fresh, and have not been rained on for a season, or worse.  Keep your eyes out for freshly fallen trees and get the bark when you can, storing it for later.  It is possible to use weak-ass materials, but it is not practical, nor very fun, and the results are likely to be disappointing.  In most cases, older trees have bark that contains more tannins than younger trees.  Stripping saplings may work, but be prepared to do a lot of it!  When you get that good material, chip it up fine.  Boiling large pieces is another common mistake.  You just can't tan an elk skin with some big chunks of old dead pine bark floating in a tub... not gonna happen.

Gather fresh material whenever possible.  Old dry bark that has sat out in the rain is poor in tannins.  Be opportunistic as here where we are gathering bark from a tree that fell across the road.
Gather fresh material whenever possible. Old dry bark that has sat out in the rain is poor in tannins. Be opportunistic as here where we are gathering bark from a tree that fell across the road.

Making the tanning solution too weak:  This problem can happen for numerous reasons, some already covered above.  Many people are so terrified of case hardening, that they start with a very weak solution and then finally end up with a solution that isn’t even strong enough for a good starter.  The skin can be put into a pretty strong tea in the beginning without adverse effects.  It can also be brought up in strength very quickly once the skin is partly tanned.  For instance, you can go from weak to medium over the course of a day and have the skin in a fairly strong solution on day two.  Case hardening is not common and in my experience must require a verystrong solution.  I’m not even entirely sure I’ve even ever seen it at all!  I just threw some squirrel skins into a full strength tanoak tea and they came out soft and beautiful. (full strength meaning shredded tanoak bark just covered with water and boiled for hours, like the picture below.)

This bark liquor is awesome.  It's hard to produce good rich liquor like this from tannin poor materials.  It is possible in some cases, but be prepared to work at it!
This bark liquor is awesome. It's hard to produce good rich liquor like this from tannin poor materials. It is possible in some cases, but be prepared to work at it!

Not strengthening the solution often enough during tanning:  This is the most common mistake.  The skin will use up tannins very quickly in the beginning.  The process slows somewhat until the skin is struck all the way through, but it doesn’t slow down that much unless the skin is thick (think big animals like cattle).  If the tan is agitated, the skin will tan quickly and the solution can be strengthened frequently to keep the process moving along.  The typical beginner scenario is to put the skin in a very weak solution to start with, and then just leave it there until the solution becomes completely used up, which can take only a day, or even just a few hours.  If the solution is not strong enough, the skin will begin to rot.  Add concentrate frequently.  If you are using materials which are poor in tannins, you will need a lot of the stuff to tan a skin (a good reason to do smaller experiments before moving on to full skins).  Don’t judge by how much material you are using, judge by the strength of the solution and how the color is progressing through the skin.  Judging solution strengths is difficult and has to be learned by experience for the specific materials you are using, but I also just don't think it matters that much unless it's too weak, which will be fairly obvious with a little experience.  From what I hear from other people, and judging by my own experience, I’d say that a rule for beginners might be that if you think it’s strong enough, it could probably be a lot stronger.  After the color reaches the center of the skin, most of the tannin binding sites are taken, and the fiber takes up the solution only very slowly.

This is one weak ass tanning solution.  There is basically nothing left in here to tan the skins.  Color does not always mean available tannin.  Add concentrate frequently.
This is one weak ass tanning solution. There is basically nothing left in here to tan the skins. Color does not always mean available tannin. Add concentrate frequently.

Not moving the skin enough:  This mistake is probably most important to avoid during the tanning phase, but it applies to many of the processes, such as rinsing out salt, liming, de-liming and tanning.  Any time a skin is put into a solution, stretch it over and move it around to be sure it is soaked all the way up in all areas.  Several visits may be necessary if the skin is not well soaked up to begin with.  Air bubbles trapped in the skin can also be an issue.   Many beginners stuff skins into a bucket or vat and just leave them.  The skins must have solutions contact all surfaces to be processed evenly.  It’s okay to fold or wad hides into containers, but there should be adequate room, and the skins should be stirred several times a day for the first few days and then occasionally until finished.  If not, they will not tan evenly and can finish uneven in color.  A good strategy for small containers is to remove the skins and put them back folded differently each time.  Just do it often enough.

This skin was dropped in the solution overnight and left there.  Think what would happen if the skin was never moved?  There are exceptions, but generally speaking, more the skin is moved, the more evenly and quickly it will tan.
This skin was dropped in the solution overnight and left there. Think what would happen if the skin was never moved? There are exceptions, but generally speaking, more the skin is moved, the more evenly and quickly it will tan.

Drying the skin without oiling:  This practice usually leads to brittle leather and cracking grain.  It is best to oil or fat-liquor the skin once it is tanned, and before it is dried out.  Otherwise the grain is generally brittle and liable to crack on bending.  Oil functions somewhat like moisture does in living skin, providing lubrication for the fibers and engendering suppleness.

Oiling the skin re-lubricates the fiber and makes for a more wear and bend resistant grain.
Oiling the skin re-lubricates the fiber and makes for a more wear and bend resistant grain.

Bad water:  Water with iron can make skins dark and brittle.  If you have to use high iron water, try to keep the time the skins are in the water to a minimum.   If you have very hard water,or especially if it contains iron, consider collecting rainwater for liming and bark solutions.  It is difficult to collect enough rain water for rinsing processes however.

Whelp, there are of course a lot more details to fill in but, given a basic working knowledge of tanning, that's actually most of the wisdom you need to know to successfully barktan skins!  If you know someone dabbling in barktanning, send them this post.  We rely mostly on word of mouth to get people here.  Please let us hear your experiences and experiments in the comments section.  Hopefully we'll be adding Barktanning to the Paleotechnics class list sometime in the near future!

Posted on April 13, 2013 and filed under Animal Parts, Tanning.