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

grain header

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 which has sat out in the rain will be poor in tannins. Be opportunistic as here where we were gathering tanbark from a tree that fell across the road.  Weak-ass materials = weak-ass results, or at the least, a lot of extra work.

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 very strong 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 difficult to produce good rich liquor like this from tannin poor materials.

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 tanning solution. There is basically nothing left in here to tan the skins. Some weak residual color such as this, does not always mean that there is any available tannin left at all, and certainly not enough to matter. 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 and slicking out a side of bark tanned bull leather.  Oiling the skin re-lubricates the fiber structure and makes for more bend resistant leather and wear 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!

Advertisements
Leave a comment

57 Comments

  1. Dennis

     /  May 20, 2013

    I have made all of these mistakes and ruined many hides. So sad to think about…Using nice hides to begin with can’t be emphasized enough. Here’s a couple more from my experiences bark tanning.

    Wasting bark/tannins: I used to boil bark and make tannins solutions like hot tea tosing the bark after I drained the solution out. Not anymore as I’ve learned that wastes bark tannins (especially when using low tannins sources). Instead I make a cold press and keep adding the cold press to more bark to bulk up the strength. If you’re using Hemlock, Pine, Alder, Willow, like I am I would cold press in at least three successive soaks. Tanoak, oak, oak galls is another story as they are so high in tannins you can get away with being quicker/soaking bark less (I only have experience with Oak Galls, so take that for what its worth) . When soaking hides in solution I also just add the old bark to the container to keep drawing tannins out and hold the hide down in the tea. Puckers from hides peeking out of the solution is another common mistake I’ve made, and I solved it with adding the bark back in.

    [Adding to the comments on moving the hide often] Containers: Use large containers for deer hides and larger hides. That five gallon bucket looks really tempting. Kick the bucket away, don’t even think about it (it is OK for sheep hides, small goat hides, squirrel, etc). Use a large 18 gallon tote at least if you’re on a budget. 55 gallon barrels and, of course, old oak wine barrels work amazing (especially for multiple hides). One cool thing about buckets is you can put the small hides in, put on a secure lid, and kick it around to boost penetration of tannins.

    Getting the membrane off: In the middle of tanning I scrape the membrane off to increase penetration. It’s easier for me to do in the middle of tanning instead of at first.

    Softening: I used to think bark tan would only come out hard/orange peel like. Using a steel spring for a lawnmower engine and stretching it out as a softening cable on a post, plus lots of brains/neetsfoot oil/emulsion, I can get hides very soft and nice by scraping the flesh side. If I want boot style leather I don’t bother with softening and just stretch out on plywood. If I want stuff to wear (or for book covers, etc.) I soften really hard until dry, adding fat as I go so the grain doesn’t crack (a spray bottle of neetsfoot really helps for this). The neck poses the most difficulty especially as you can only soften the flesh side.

    OK, this is really long…

    Thanks for the article! I wish I had this three years ago! Hopefully less hides will go bad and more beautiful leather will be made as people continue to unravel this complicated art.

    Reply
    • Thanks for the great experience Dennis! Between my post and your comments, barktanning novices with basic tanning skills should do pretty well. I do two or three boils with the same bark, using the second and/or third boils to start the next batch of bark, or to start skins in. Anymore, I sort of just use whatever solution regardless of the strength. I think it’s probably actually Ok to use a weak solution if it is changed or moved often, but it rarely is. At least that is my leaning right now. What I don’t want to see is skins left in weak solutions for a really long time, which they usually are. Even a medium strength solution is stripped out pretty fast, especially in the early part of tanning. We should be thinking in hours rather than days, at least at the beginning. Another thing I’ve learned is that color does not necessarily equate to tannin content. A used liquor will not be clear and the color remaining is not necessarily useful for tanning.

      I think people can get away with really small containers if the skin is moved a lot, but I agree that the bucket is just not an ideal shape/volume ratio. the rectangular tubs fit skins better in general and the 18 gallon totes can do a lot of stuff, even sometimes cattle sides and bellies if the they are accordion folded in and removed and refolded frequently. I just tanned some skins in a cooler which was not ideal, but they turned out fine in the end, in spite of being wadded up in there a little too much.

      I like to do a decent job membraning before tanning, but perhaps you’re right and it’s not even worth it. As long as the skin is scudded thoroughly, which often removes much of the membrane, I think it’s probably fine to membrane sometime after the skin goes in and I do it anyway to get the remaining membrane off. I agree too that it is a good way to work the skin open and increase penetration. Sounds like we probably agree on most stuff.

      There is definitely significant difference in how hides turn out depending on what was done to them before they go into the tan, and to at least some extent, how long they spend in what strength of tan solution. There is a certain level of drape and suppleness that comes with losing some hide substance along the way. Losing the least amount to get the desired effect in drape and lusciousness is what we all need to figure out. Working the skin very hard, like buckskin must help. I have been using olive oil/egg yolk emulsions with light grain oiling during softening, much as you describe. I tend not to work the skins very hard though as I have limited time and energy and also have other stuff I’d rather be doing. I’ve also been working on bating experiments lately, but it is difficult to judge and control.

      What’s your take on case hardening or the qualitative effects of putting skins into very strong solutions?

      Feel free to comment extensively. I have to go deal with some hides I’ve been procrastinating on for way too long! ;)

      Reply
  2. Dennis

     /  May 21, 2013

    Steven, Thanks for your reply.

    Membraning: I don’t know if I recommend it as a preferred practice–I probably delay penetration and waste tea–but it’s just something I always end up doing. And it seems easier because the hide is more firm and gratifying to scrape off. In a way I consider it part of my currying process near the end of the time in the tea.

    Case hardening: There’s a huge difference to me between Hemlock tanning (catechol) vs. Tanoak (hydrolsable tannins/gallo tannins). I have messed up hides with too much hemlock too fast; the puckering never went away even with weaker hemlock teas. With Oak Galls I never experienced puckering no matter what the strength (but my sources are limited as prairies and oaks are rare here). I have completely “mellowed”/fixed astringent/puckered hides with gallotannins (chestnut extracts, oak galls). There’s still visible defects in the hide but the hide still turned out OK rather than just a failed bark tan for the compost. If I had abundant gallotannins I would just go full strength in one day; I have friends who don’t even bother with weak teas on deer, goat, sheep hides and report no problems. My guess is case hardening is basically irreversable puckering from catechol tanning and mellow oak tanners should just ignore the warnings.

    Stacking skins in small spaces: As with case hardening, hemlock tanning in small bins is sketchy for me, especially at first. Stacking a bunch is even worse. With gallotannins I would stack two to three per bin (with bark in between) and just go full strength all the way. I bet Miles of Courtenay BC, or Daniella, or other Cascadian hemlock bark tanners might say something different…

    Bating/deliming, etc.: I’ve experimented with a lot of weird techniques but have never done the chicken bate. I just can’t do it. I’ve gotten goat hides from Fez, Morocco–just to see how the pros do it–and they smell like pigeon shit. Forever. No thanks. So I’ve done mostly vinegar baths and that has worked great. One time I got a papaya because I heard they drop a hide like nothing else, and it did (you’ll notice in the health food section papaya enzymes for sale “for digestion of fats, carbs, and proteins”). And it smells great! But of course it’s not very practical. I think what tanners are wanting from beer dregs, bran drench, pig pancreas, chicken shit, papaya, fermented piss, sour brains, and everything else is: acid/low pH producing bacteria and enzymes to break down the lime and pre digest the hide. This makes me think that maybe kombucha, sauerkraut, yogurt, sourdough could be possible practical home solutions for bating and better smelling than chicken, dog shit, sour brains. In a Herman Oak video on youtube, one of the last industrial bark tanners left, they drop hides with enzymes “people use everyday in cleaning products” like Bac Out or other enzyme cleaners. I’m not going to use Bac Out but it gives me a point to reverse engineer the industrial process. Bran drenches never did much for me and seemed like a waste of time.

    Finishing bark tan like brain tan: I would try it at least once, or if your wanting a hide for a specific project that’s especially soft. It did take me eight hours to finish two hides, so yeah I can see why most people wouldn’t bother. I’m trying to make no tech rain gear as it rains here 8 months out of the year (in Olympia, WA) and need more pliable material. Having been working on store bought scraps of bark tan cow leather I’m actually thinking of finishing my next batch orange peel style to so it’s easier to work on/lays flat for bags, belts, boots, etc.

    The next step for me in this is figuring out “rapid” tanning techniques with pickling, pre-smoking, and other techniques…One experiment I’m going to work on is pickling hides (with salt and vinegar) and rapid tanning with catechols like it was gallotannins; supposedly the pickling will prevent puckering.

    Check out these resources. I consider them way better than Reed, Odle or other sources:

    http://books.google.com/books?id=RaZRAAAAYAAJ&printsec=frontcover&dq=Hippolyte+Dussauce+leather&hl=en&sa=X&ei=tiibUYCMCe_oiwLPxYHIAQ&ved=0CC0Q6AEwAA#v=onepage&q=Hippolyte%20Dussauce%20leather&f=false

    The most interesting thing in this book is that there’s a method for using Yellow Clover as a mellow tannin that I want to try out (I plan on growing yellow clover as a cover crop anyway). Pre-smoking methods are also described. I’m really into figuring out homestead techniques that don’t require, or might off set, scrambling for tree bark.

    This is the best referrence for bark tanning I’ve found, especially on how to make concentrated teas. The bag tanning techniques mentioned are interesting as they require no bin: the hide is the container! I think this is where I got the papaya idea.

    Reply
    • Interesting on the different tannin types re: case hardening. I just dunked a bull hide in a pretty strong tan oak tea, so we’ll see how it goes.

      The hen bating isn’t as bad as it sounds actually, and I’ve not noticed a residual smell yet. Other lactic ferments like yogurt can be used to drench, but I doubt that drenches have the same effect, or at least not as profound. There is a book on Bating and Drenching that says drenches are more for removing residual lime that can’t be washed out with water and that the softening effect is minimal. ( Puering, Bating and Drenching of Skins by Joseph Turney Wood ) I believe that vinegar is also considered less effective at lime removal. I’ve used vinegar and can’t say that I’ve noticed a qualitative difference in vinegar v.s. bran drenched, but haven’t done A/B comparisons yet. Drenching is quite easy, so I’ve gravitated toward that. Vinegar seems easy, but it doesn’t appear to have been very common in the old days. I’d of course like to use something more pleasant and less dangerous than poop for drenching, but I don’t want to buy anything and I’d like to do it enough to figure it out. So far bating with hen dung has shown mixed results and high variability. One interesting thing I learned from the Turney book is that dog dung puering is more softening and less penetrating. Bird dungs at low temps were used on heavy skins because they are slower acting and they wanted to be sure the effect reached the center of the skin before the outside was over bated. Apparently thin skins can be bated at a higher temperature.

      I think handling (in any way) and moving the skins goes a long way in speeding up the process. In the buckeye bark tan class, we scud the hides several times a day and stir them frequently adding tea a couple times a day to strengthen. we haven’t had a hide fail to be finished in the 4 days or so that we have to get them penetrated all the way (goat skins). I think scudding out really helps to open the skin back out after the initial tannin shrinkage, improving penetration. I’ve found that the membrane will come off really easily once the skin is even a little stiff from the tannin, which isn’t very long. It was very common to pull skins out and let them drain at least once a day to speed the process (assuming they weren’t in layers with bark). At Muir McDonald, they had big rockers that kept the skin in constant motion, which obviated the need for all that handling. I’m thinking that wind could be harnessed for that purpose without too much effort. An old Cherokee account mentions a hollowed log that was placed in a high traffic area so that anytime anyone walked by, they gave it a shove to rock it.

      I like the Watt book a lot. Those older technical manuals are harder to wade through and require some tanning knowledge, but that’s where a lot of the interesting wrinkles are.

      Bark Peeling: yeah, early. April to July here.

      Black Dye: I’ve messed some hides up doing black dyes with iron. My take anymore is use the least iron possible, applying weak solutions several times if necessary. Also, rinsing the dyed skin in weak tannin and then rinsing very well to remove any unbound residue. I don’t have a “method” yet, as I don’t do it often, but that is my leaning now. At Muir McDonald, they told me that they used to use urine somewhere in the iron blacking process, but not sure where.

      Thanks for the links. I’ll check ’em out.

      Reply
  3. Dennis

     /  May 21, 2013

    Forgot a couple more things:

    Collecting bark: I collect bark whenever, but the best bark is available right now (May, June). It’s the easiest to collect (peels off rather than coming off chunky like in the picture above) and is the highest in tannins. Look for fallen trees after big wind storms…I’ve used a machete, axe, drawknife…

    Small experiments: if you’re not sure what your doing, why waste a hide? Just cut off a piece of a small hide and experiment in mason jars. This would also help if you want to see the results of different tea mixtures.

    Black leather: Vinegar and rusty nails. Dub on before the dubbin for black leather. I’ve noticed this works best on hemlock. Some hides I’ve had turn greenish black, not jet black.

    OK, that’s it for now.

    Reply
  4. Alicia

     /  October 28, 2013

    Thanks for all of this information and experience.

    What about using redwood or bay laurel bark? Tannin concentration, resulting qualities of hides tanned with either?

    Reply
    • There is a book on redwood: Redwood: a report of fundamental investigations and related application studies for the Pacific Lumber Company, 1937-1945 that has some information, but I cant find a place to read it online. It is available through some university libraries though. http://www.worldcat.org/title/redwood-a-report-of-fundamental-investigations-and-related-application-studies-for-the-pacific-lumber-company-1937-1945/oclc/3838538

      you can read a couple partial snippets here: http://books.google.com/books?id=vDvxAAAAMAAJ&focus=searchwithinvolume&q=tanning

      I had a reference some years back that mentioned all the materials that have been tried in California, but I can’t figure out what it was. I remember one was gold cup oak acorn caps, a.k.a. Canyon live oak: http://en.wikipedia.org/wiki/Quercus_chrysolepis I’ve used them to dye buckskin a nice light tan color. There are so many oaks in California that I think no one really bothered to branch out much, though investigations were obviously made. As resource greedy and mindless as people were, some could still see the tunnel at the end of the light coming. If you have redwoods, you usually have a bunch of overcrowded tanoaks, and the health of the forest and remaining trees could often benefit from removal of some of them. It is also not uncommon to find freshly fallen oak trees that you can strip for tanbark. I don’t want to discourage you from experimenting though. I’d start with very small samples, like a few square inches, just to see what it’s like and how much material you need before diving in to a larger skin. Squirrel skins make good experiments, and nice leather. Please report back if you try either!

      Reply
  5. Tom

     /  December 17, 2013

    Appreciate the information! I am trying to tan a deer hide and it went ok so far, but after 4 days in progressively stronger liquor, it is tanning unevenly with large areas coloring nicely but some spots not coloring hardly at all (mostly around the edges). Any suggestion on what I have done wrong or how to fix at this stage? Hair and membrane came off fairly clean but I’m not exactly sure how much of the tough fibrous stuff to take off the flesh side. Using very dark hemlock liquor in a large shallow pan so the hide lays almost flat and moving around a few times every day so no folds or bubbles remain. Not quite sure what to do next. Any suggestions would be appreciated.

    Reply
    • Usually that is from uneven access to the tanning liquor. I’m not sure what else might cause it. You might be surprised how little time it takes to end up with uneven coloring, even when moving several times a day. Usually it evens out though if you do keep moving it, so if it’s not doing that after 4 days, then I’m not sure. It would help to look at it. You can send me a picture maybe? The more you get off the flesh side, the nicer the finished leather is. Just throw it back on the beam now that it’s partly tanned, and flesh over it. The stuff will come off a lot easier now. Did you lime it? Are you sure the parts that are not coloring are fully soaked up and not dry at all? What about grease in the skin? That would probably prevent binding of the tannins. It is completely submersed all the time? Hard to say if I can’t examine it, and no saying I would no for sure if I did. If you can give details on what you’ve done so far and what state the skin was in to start with that might help.

      Reply
      • Tom

         /  December 18, 2013

        I don’t think there is any contamination of grease on the hide and I am sure that all parts have been kept fully submerged and wet in the tanning liquor.
        I did use a lime and ash mix to de-hair. (1/4 cup lime and 1/2 cup ash per gallon of water) for a couple days until the hair slipped. I think I should have let it soak longer as it took a fair amount of effort to get the hair all out. Let it soak for one more day and finished removing the tougher hair from the neck area. Then I rinsed it out with several changes of water and soaked in water with a cup of vinegar to get the lime out. A day of this and then I pressure washed the remaining ash off of both sides. Maybe I should have soaked longer or with more vinegar?
        Then I put it in the first batch (third pour cut with water) for a day and the next day I added rest of third pour. Day three it went into straight second pour and day four I added some of the first pour to strengthen it. Prior to soaking in the second pour on day three, I dumped out the first batch in case more lime leached out into it.
        It seems that the thicker parts of the hide (near the back and neck) are tanning much better and the thin parts (just forward of the hind legs) are not taking color well at all. I’ll e-mail some photos so you can see what it looks like. Thanks again for the suggestions and the great article.

      • Most of that all sounds pretty good, except, yes, let the lime work longer. It may have been too weak too. I don’t have a formula for using builders lime (type S) which is what you probably used, but that seems reasonable, especially with wood ash, which is generally around 30% lime I believe, plus the potassium hydroxide. And, yes, probably should have de-limed a little more. It’s something that is easy to under-do. In my experience, it will make the finished skin dark and brittle. Vinegar is not that effective in removing residual lime. It is best removed with a bran bate, or by soaking in one of the manure solutions, like hen dung. Just mix a little chicken poo in water and let it start fermenting a bit, then throw the hide in, Same with bran drenching. Wheat bran from the feed store. throw in a double handful or two and let ferment. Either solution will damage the skin if over done. Scudding is also important. No amount of rinsing and treating in solutions will clean out the lime and skin fiber without mechanical action. Scud out many times between rinses and solutions. Think of the skin as full of junk and you are really trying to push everything out that is at all soluble, leaving a clean matrix of fibers. It is impossible though to remove the lime with and scudding alone. None of this really answers your questions though. my only possible thought is that the thin areas were more thoroughly de-limed and are coloring lighter. A well de-limed hide, can turn out quite light in color. Check out commercial bark tan. It is usually very light tan or pink. For me to get a very light hide, I’ve had to bate skins though. And, that just doesn’t seem like it’s likely to be the problem. Your solution procedure sounds good, but I’m not used to using hemlock. See Denis’ comments below.

  6. Tom

     /  December 18, 2013

    Also….skin came off a mid sized buck around Dec. 1st. Few wounds and a bullet in and out but not too many abrasions. Flesh and fat came off fairly well with a few hours of effort and I salted and froze the hide two nights between cleanings prior to the ash and lime bath. Hope this helps.

    Reply
    • That sounds good. Fresh is good. No need to salt when freezing. Also, when scudding, it helps to get what you can off the flesh side. That’s where you want to be scudding anyway, using the fleshing tool. By the time you’ve scudded it 6 times or more, most of that membrany stuff will be gone. The rest can be easily removed at the stage you’re in now. Fear not, in all likelihood it will make something useful! And it’s a great learning experience. Sometimes you just have to jump in to even know what questions to start asking. Way to go, going for it. Anymore, I’m inclined to recommend people start with a squirrel though :D

      Reply
  7. benadett

     /  February 1, 2014

    am a beginner in tanning from kenya,africa. One of my experimenting sheep skin has white spots on it although it has been in the tanning liquor for 2 weeks. What could be the reason?

    Reply
    • If it is not moved often enough, that can happen. Usually it will look like streaks or you can tell it is where there were wrinkles in the skin. Otherwise, it’s hard to say. You can try to send my pictures if that is possible. Sheep skin can be difficult to get the fat out of. Is the hair still in?

      Reply
  8. benadett

     /  February 8, 2014

    benadett, frm kenya, africa. Thanks steve for your reply. Yes, turning regularly could have been the problem. I would like to know whether driers could be used in a small scale tannery for drying and tumbling of sheep skins. What else can i use.

    Reply
  9. I think a drier is an interesting idea. It would depend on what type of leather you were making though. If you want to soften the leather thoroughly, you might try tumbling it with a shoe to soften and break it up. I think you are probably better off softening by hand though. Bark tanned skin is not difficult to soften.

    Reply
  10. benadett

     /  February 9, 2014

    thanks for replying. But am wondering how i should use a shoe to tumble. Should i spank it with the heel?

    Reply
    • In the dryer. I’m assuming you meant a tumbling clothes drier. As the drum spins, the shoe beats the skin in the drum. It’s just something soft and heavy to beat the skin in the drum.

      Reply
  11. Alicia

     /  May 21, 2014

    Hi,
    I have a few hides that were wet-salted for a year and a half and I just pulled them out to tan when I found some pink mold areas on the flesh side of all of them. Upon rinsing them to rid the salt and prepare for bucking, two of them appear to be in good condition while the other’s hair slips readily. I’d rather not waste time on crappy hides, but I’d really like to make use of them if your experience suggests they’ll make decent leather. What are your thoughts? If you don’t think the mold is a problem, any suggestions for the one with hair slipping so easily – better luck to bark vs brain tan?
    Thanks!

    Reply
  12. Alicia: The pink mold is common and doesn’t seem to cause any major issues in my experience. As to one slipping more than the others, who knows. Maybe it was already not so fresh when put in the salt, or maybe it was not salted thoroughly, or soaking in salt slurry. Hard to say if it will be an issue. If you haven’t bark tanned before, I’d actually start with a smaller skin, or just a portion of a deer skin. My current favorite to introduce people is squirrel. They’re small so they don’t require a lot of materials, you can learn a lot, and you’re not out much if things go south. a quarter of a deer or goat skin is pretty manageable too. One thing with bark tanning with the grain on is that you’re going to see any blemishes on the grain. Sometimes minor damage can happen during long salting, or if the salting wasn’t done properly. It’s kind of a crap shoot. If the skins seem to be in good condition, it is probably fine. Hard to say much without seeing them though. I certainly prefer to bark tan fresh skins rather than salted when possible, but I’ve done plenty of both and the salted often turn out just fine. Hope that helps. It could probably be of more help if I could see them.

    Reply
  13. Alicia

     /  May 27, 2014

    Thanks, Steven.
    Do you acidify your hides for bark tanning (after rinsing, before membraning)?

    Reply
  14. I’ve used vinegar a lot, but it doesn’t work as well as drenching in bran and bating do, though it’s probably better than nothing. I know it is not effective at removing the last of the residual lime. Drenching in bran is easy. Just mix a few double handfuls in a bucket with water let it start fermenting and toss the hide in till it floats to the top. Some sources say to push it down and let it rise one more time. But, it’s not rocket science. Just don’t leave it in too long or it can be damaged. More important than all that is thorough scudding before and after. Chemistry alone won’t do it. You have to manually flush lime out of the skin. You can get bran at a feed store, usually in bulk. I think any source of starch would probably work, but haven’t tried others yet.

    Reply
  15. Dino Zack

     /  June 15, 2014

    Wow, great info! I wish I would have read this before I started. I don’t want to take advantage of your tanning knowledge but was hoping you could help me with a “few” questions I have on the process.

    First a little background; I am a proficient hunter, hobby trapper, and primitive bowyer, and have lots of experience handling and putting up my furs and working with wood. I read all I could find on brain tanning and tanned four hides over the past couple months (could not find brains so I used egg yokes and a little Castile liquid soap as my dressing)…the last hide turned out better than the first and I learned lots about the process by diving in. By talking to and showing my hides to some experienced tanners I think I understand some of the issues I have been having.

    Regarding bark tanning; I tanning whitetail deer with white oak inner bark.

    I figured I would number my questions/comments to make it easier to respond to.

    1. Liming verse Bucking. Is the goal the same; to get hair to slide, swell hide so grain can be removed easier, and have mucus work its way out of the hide? I started with ash and have now been using Sodium Hydroxide (pH 14). Is Sodium Hydroxide considered liming or bucking? Because I left the grain on my hides for bark tanning, can I stop soaking as soon as the hair starts slipping? Regarding procrastination, I was in the middle of traveling during this process and the hide may have soaked longer than idea…sections started to turn to clear gel…is this hide glue?

    2. Drenching verse neutralizing. Does drenching refer to the use of acid (vinegar, poop, etc) to neutralize quicker than rinsing (anchor hide to rock on bottom of river)? Pros/cons either way?

    3. Is Scudding the same as Scrapping? Or is scudding squeegeeing?

    4. During bark tanning process, is the grain side off limits after hair is removed (i.e., as to not damage the layer)?

    5. Bark solution. Looks like lots of different techniques. Any issues/comments with the way I handled this step?

    -hand shredded 10 pounds of white oak to get three 5-gallon pours (correct ratio?)
    -boiled each batch in two pots (2 gal and 3 gal) for 1.5 hrs and poured off through cheese cloth (is straining needed) into separate 5-gallong plastic pails?
    -I boiled bark in Al pot…is AL ok to use or do I need stainless?
    -Rain water verse tap water verse river water…I understand the Fe issue but is there an issue with organics in the river water with the process…does the tannin go to organic matter instead of hide or is such a small amount of tannin lost that it doesn’t matter?

    6. Case hardening. Some say yes, some say no from what I read. Should I go to first pour using white oak or move through each of the pours; weak to strong?

    7. Soaking time. Some say 6-12 months, some say 4 days…very big difference. I’m I looking for color to know when done or do the tannins need the time to do their “thing”. What would happen if I started to stretch/dry a hide following neutralization, i.e., no brain/egg dressing or no tannin?

    8. I noticed the pH of my bark liquor following my first soak in the third pour was pH 7/8…pH of second pour before hide is pH6…I’m assuming due to residual sodium hydroxide.

    9. I put three small deer hides into 5-gallon plastic pail with bark liquor…I will use large bin next time. If I have three hides in one bucket, over time (days/weeks), with the tannin reach the entire hide if I mix periodically? I will use bigger container next time.

    10. Wringing/stretching. Should I wring/stretch hide to removal water from hide following neutralization and pre soaking in tannin? I tried to wring hide but with grain on it was very slippery and I was not able to do a good job…I used my scraper to squeegee water and remove residual membrane. Would it be helpful I try to wring/stretch (scrape) hide between soaking in different pours?

    11. Does the tannin “push” or “replace” water in hide? From what I read for brain tanning, all free water must be removed so dressing can penetrate into hide and not be “blocked” by water.

    12. Time in tannin liquor. Regarding brain tanning, the longer the hide sits in dressing, the easier to break. Does soaking time (short/long) in tannin effect the hide? Pros/cons?

    13. Processing bark. Does it mater if I process (shred) bark wet or dry? Can tanning stay stored in bark if I keep “raw” bark in a plastic bag? I assume yes as it is not leaching out anywhere.

    14. Do walnut husks contain tannin? Can I use them to stain leather? If so, at which step? I would like to make dark brown leather right now.

    15. Oiling. Can I use my mixture of egg yoke and liquid castile soap for this phase or is there a better “oil”? If I use the above mixture, would it be good to soak bark tanned hide in the mixture as if I was making brain tan hide?

    16. I use beaver tails to wrap my bow handles and carp skins to back my bows…these are applied “green”…I air dry then rehydrate when needed. I would like to try and bark tan them…does anyone have any experience bark tanning beaver tail or carp skin? More interested in bark tanning carp skin as I think the contrast between the dark tan and scale texture/pattern would be cool (note I remove scales). Also, both are VERY oily…I wonder if I soak in sodium hydroxide it would help (I think it would ruin the beaver as it would cause the tail scales to slip) with loosening the scales on the carp skin…I typically soak the carp skins in dish soap for a few days to loosen the scales.

    Well, many more questions than I originally anticipated. Hopefully the answers to these will also help others. It will definitely help me as I would rather not “re-invent the wheel”!

    Thanks in advance for any help!!

    Dino
    dinorocks@gmail.com

    Reply
    • That is a lot of questions! It will take some time to answer them in any detail at all. I’ll see if I can get to answering some of these, but it’s a bit of a project. In the meantime, start smaller! Literally, very small sections of hide and squirrels are great to learn on. Not much investment in time and materials, for a big return in experience. Also, when you have so little invested, it is less risk to experiment with things like case hardening or bating. I’m planning to post more on barktanning in the future, and hopefully a few videos too.

      Reply
    • Dino:

      Your buck may be a little strong there. I just use lime, which is traditional, can be made at home, and can’t be made strong enough to damage the skin except with very long soaking times. both have the same goals, to remove stuff that isn’t collagen, and weaken or remove defensive mechanisms of the skin that protect it from chemical attack (like tanning).

      I think I’m referring to soaking in a fermenting bran or other carbohydrate solution when I say drenching, though some use it to refer to any acid treatment. soaking in water or vinegar allegedly won’t remove all of the residual lime, but it can be adequate with enough scudding. I like the bran treatment so far. soak a few handfuls of wheat bran in a bucket with water till it starts to ferment, throw in hide till it rises to the top. Some say push it down and let it rise one more time. Overdoing it can certainly damage the skin. Of course follow with thorough scudding and rinsing.

      Scudding, however it is performed, is just pushing liquids and solids out of the skin between rinsings. Re-fleshing is a good way to go, but the grain should be gone over several times as well. Don’t skimp on scudding! I used to think it wasn’t that important, but it is very important.

      Shredding bark finer yields more tannin. Multiple extractions help get all the tannin out. I just put bark into the pot and cover with water, for the strongest extract I can get. you can always dilute. Then do usually one more extract and possibly a third to pour in to the next batch of shredded bark.

      rain water good. river probably fine if not heavy with sediment.

      Not sure about aluminum, I’ve always avoided it.

      No real reason I can see not to work from weak to strong solution anyway.

      Keep solution strength up and it should be done when fully penetrated through. Usually stuff is only left in longer to “fill” the leather more for specialty leathers. Don’t need to worry about that now, just tan them and see how they turn out. If left in weak solution a long time, the coloring matter (not necessarily tannin) can penetrate through with only a minimum of tanning going on. Again, keep up solution strengths to a reasonable degree.

      Not sure about drying the skin post prep and pre tanning. I haven’t tried it. Let me know what happens if you try it.

      Soaking time can vary. We pull off goat skins in 5 days at buckeye gathering (already limed adequately before class starts) by frequent handling and steadily increasing bark liquor strength.

      Use a bigger container now, not next time.

      cutting bark when wet is easier. Walk on it with boots on a tarp when it’s dry to break up more. easier or not, I just do it when I have the time and energy.

      Read Denis’ comment on case hardening in the comments. I think with white oak, you’ll be hard pressed to case harden. cut off a small piece and throw it in the strongest solution you make. I’ll bet it will tan quickly and come out fine.

      Skip the wringing all together. It’s best to have the skin uniformly soaked up, or stretch it immediately in the liquor to get it soaked all the way up. Re-fleshing between soaks is a good idea. It will open the skin fiber up and compensate for some of the shrinking the skin generally undergoes when soaked in tannin. More frequent handling of any kind will speed the tanning process.

      I haven’t tried over dyeing with walnut, but I’ll bet it will work. Walnut hulls have less tannin and lots of coloring matter. I know someone who did a whole skin with them, but it took a crap ton of hulls. not recommended. Remember the leather darkens a lot with use too.

      For oily skins, throw cornmeal on them as you flesh to absorb fat. Liming/bucking sounds like a good idea too, and just lots of fleshing, scudding, rinsing. You definitely want to get the oil out. Lotta Rhame wrote a book on tanning fish skin. I haven’t read it yet, but she’s awesome! I don’t have experience with fish skins at this point.

      Reply
  16. Dino

     /  June 30, 2014

    Thanks so much for taking the time to read and answer my questions! VERY HELPFUL!! I will be pulling my three deer hides out of the bark liquor soon…I will let you know how they turn out. I have three more hides in the bucking solution right now which I plan to brain (egg) tan.

    I will look up Lotta’s book…sounds like it will help me.

    Thanks,
    Dino

    Reply
    • You’re welcome. Lotta has another book on tanning in general that was just re-translated and re-released in the states. We don’t carry it at paleotechnics yet, but we may soon. I’m not sure of it’s availability beyond ordering it from her in Sweden. It’s definitely worth checking out. Here is her website link. http://www.lottasgarveri.se/Garveri.html Lotta Rocks.

      Reply
  17. Jason

     /  February 13, 2015

    I just finished a batch a pronghorn skins. I limed them, de-limed with wheat bran, and tanned them in layers of hemlock bark, they soaked about 4 months. They came out good, except they seem to “open” and somewhat spongy, with hardly any water resistance. I test water resistance by making a fresh cut on the edge and placing a drop of water on the cross section. Ideally the water drop should sit there beaded up for awhile and not soak into the leather. This is how my deer skins turned out that I tanned in douglas fir bark. Other than using hemlock bark and pronghorn hides the only thing I did different was the wheat bran drenching. Do you all think I left them in the wheat bran too long and damaged them from too strong a ferment? Or are pronghorn hides just open and spongy….or is hemlock bark low on the water resistance scale? Just trying to figure out if I did something wrong or am just missing something? Any comments would be appreciated. Also how much oak galls do I need to tan say…. one large deer hide? Thanks. Awesome site!

    Reply
    • Hi Jason: I have limited experience with Pronghorn, and only in braintanning them. My impression though was that they were closer to goat than deer in texture with a tight, fine fiber network. Possibilities besides the nature of the skin itself are, as you already mentioned, drenching strength/time, liming time, any other periods where they soaked in water for a while, and weak tanning solution. Pronghorn are thin enough that you should be able to tan them very quickly. Goats can be done in a matter of hours if manipulated constantly in a warm bath, and we do them in a few days in classes by just manipulating them a lot and steadily raising the strength of the solution. It may be that you just left them in for 4 months in a strong solution, but if it actually took that long to strike through the neck or other thick parts, your solution is probably too weak. Using weak solutions high in bacteria and bacterial by-products has been one strategy used to modify the character of the leather. Layering is usually used after initial tanning in solution. The hides are then laid away for a while in layers of bark. Maybe you can write more about what you did and times spent in various solutions and rinsing, but I’d say if you want dense leather, move things through quicker. Drenching is a pretty brief process in my experience. mix it in, let it rise to the top, and maybe push it down and let it rise one more time. And, I have damaged hides during drenching. Water resistance isn’t something I’ve paid much attention to, so can’t help there. Also, I am usually using oak bark. Oak galls I haven’t used a ton, but they are very high in tannin and seem easy to extract. I’m not sure they make great leather. My initial impression is that they might make a brittle leather, but like I said that’s just an initial impression.

      Reply
  18. Jason

     /  February 13, 2015

    Thanks for the response. I limed some of the skins for about two weeks, other for several weeks. The drenching was also varied…some for a few hours others overnight. They were risen to the top for awhile before I took them out. What happened to the skins you damaged by over-drenching? The skins were first “colored”or “handled” in weak solutions, and then laid away in ground bark. About one inch between each skin…..the solution was definitely really strong. I left them in that long from procrastination….a big no no. I should have pulled them out to “crust” and softened them when I had time. They were probably tanned through in a month or so….although the ground bark method is definitely slower than the strong extract method. Yeah I have read oak galls can give a brittle leather if used alone…I probably will mix it with oak bark. Anyway I’ll bet if anything I over-drenched them. The leather itself is good and usable….just seemed a bit spongy to me and was trying to see if anybody some advice. I have read in some old texts about the water drop test..being used to test for properly tanned leather….so when mine failed it I was interested as to why. Your advice on moving things quicker I think is wise and I will take it…I tend to over-do some of the processes. Do you have any experience with traditional cod oil tanned leather…or thought of making it? I really want to make some but I need to figure out how to build a fulling mill. I think there is only one place left in the world that makes it in the traditional way with the large wooden hammers. The down side is, not being by a river I would need to use an electric motor to power it. Thanks again!

    Reply
  19. I think I had pitting and obvious visible degradation of the hide with over drenching, but it’s been a long time. I do remember that it happened very fast though.

    Of course it depends on the strength of the lime, bate, drench, tanning solution v.s. time soaked. In the case of lime, weaker lime can be less bacteriostatic. Same with tanning solutions. I guess drenches and bates are the other way around.

    I’m not sure long tanning is a problem as long as the solution remains strong. Most noobs lay stuff away in too weak solutions and leave them a long time expecting them to be preserved, but the skin slurps all the tannin out right away leaving a pretty much totally spent solution. Usually people end up with usable leather, but it is often “empty” (light weight and spongy) as you may be describing, and grain damage and delaminating grain are also common.

    I’ve been meaning to try oil tanning for years. I have some cod liver oil set aside. It was done in the NorthWest US by native groups using shark liver oil and the like. I think there are some accounts in our Buckskin book. I doubt you need the hammers or oxidation rooms, or any of that stuff.

    Reply
  20. Jason

     /  February 13, 2015

    Thanks. The tanning solution could have in fact been used up by the skins, and even though they were tanned through, they were still sitting in a weak solution. Probably should have taken them out as soon as they were struck through. Good call. This was a good lesson.

    Reply
  21. If the skins were well tanned before being left in the layers, I kind of seems unlikely that the time in that solution would cause it to feel very empty, but hard to say for sure. If you get some more pronghorn, try moving one through all the steps quicker and see what happens. Fast hot liming can cause rough grain, but you could do a quick bate in hen dung to smooth that down a bit if it doesn’t suit you. Scudding every few days and adding concentrate to the bath will tan thin skins pretty fast. I would love to hear about what you learn! If you don’t need whole skins, consider cutting one up into halves or quarters and treating them all a little different. That’s a good way to learn a lot fast. Once you get something that works for you, then you can run batches and get a more consistent product. It really is easy to procrastinate in bark tanning though….

    Reply
  22. Jason

     /  February 14, 2015

    Right on. I have about 30 deer skins and at least a few more pronghorn. I will do some experiments and post my results. One more question about liming. When you say fast hot liming what do you mean? I was under the impression that lime reaches a saturation point where the solution can not get any stronger no matter how much lime is added. I need to get a better grasp on this concept. I figured stirring the lime solution reactivates it. I have been making lime solutions with 1.5-3.5oz. per gallon of water.

    Reply
  23. Like everything else, there are a lot of variables in liming. There is the strength of the solution, what you are liming, age of solution and what has been in it before, dwell time in the solution etc… So, how to do you figure out what works and how to really manipulate the process to get the results you want? by doing it over and over with the same materials and hides in the same context. That is why tanneries tend to specialize and stick with what works for them. Or at least they used to. By hot I meant using a strong fresh solution that would be fast acting with a minimum of bacterial action or enzymes floating around in there chewing up the hide substance. One think you might try is comparing that to using weaker solutions or old solutions. I haven’t done as many experiments as I’d like on that (or paid enough attention to the results of the ones I have done!), but it would be very interesting to figure out just what difference it makes and how much. Fast strong liming will generally give a firmer leather, with maximum substance, but the leather feel is not likely to be mellow and the grain can be raised and harsh. You can affect that with downstream processes to an extent though, so that complicates matters more. Some of the variables are very hard to control of course, which is why I say that doing it again and again in the same context is going to give the most insight. For instance, lime is actually more soluble in cold water than in hot. Of course everything happens faster at warm temps though. Then there is the bacteria, ammonia and enzymyes in the lime bath, what kind and how much. If you’re going to do a lot of tanning, like a big ole batch of deer skins, I’d be looking for something that you can repeat and that is practical. Deer skin tends to be mellow and loose anyway by its nature. I’m not sure what’s best to do with it as a standard process, but I think a reasonably fast liming, followed by bating to mellow the grain a little and drenching to finish de-liming might end up being a good basic process. I have had it turn out buttery and incredibly warm and mellow with long liming (wood ash actually) and long tanning in weak solution, but definitely more empty and weaker than it could otherwise be. I really like bark tanned deer skin. The header at the top of this page is oak tanned deer skin worked with the grain in to make the crinkled grain look. It is fairly mellow for a fast tanned skin, but still with plenty of substance.

    Reply
  24. Peter B.

     /  March 18, 2015

    Thanks for all the great info. Maybe you could help me with a couple questions.

    Is liming and/or bucking necessary? I’m not really sure why I’d lime/buckif I’m not brain tanning. Same reason?

    You mentioned doing goat skins in 4-5 days. Other than because you used lime, is the constant scudding in your workshop similar to wringing a skin with the doughnut method when brain tanning? Just helps with better penetration and opening fibers, correct? I’m hoping to try this soon but would you think a deer skin could be tanned in a day or two if using the multiple wringings method that’s often used with buckskin? Would it be too different of a physical or chemical change to work similarly?

    I’ve had good results using red oak acorns and shells with deer, coyote, fish and goat. Some folks claim they don’t work well. I’m assuming success could be species specific when using acorns as a tannin source. Any experience using acorns?

    Thanks for any insight you might have.

    Reply
    • No, liming is not necessary. It does some useful things though. I think it depends on your goals. Don’t accept or reject it on principal, just try both ways and see how it affects the skin. If you don’t lime or buck, you can’t remove the hair unless you sweat the skin or soak it. That often results in less than satisfactory hair removal and can also lead to grain damage. It was done though. Liming (bucking is similar enough to lump together) can help clean the fiber structure to allow easier penetration of tanning fluids and can modify the quality of the finished leather.

      Frequent scudding does help keep open the fiber structure. it also removes stagnant depleted liquor from the skin so it can be replaced with new fresh liquor.

      I would not wring barktan if the grain is on. Maybe you could run it through an old washer wringer, otherwise, I think scudding is better. Scudding the flesh side also removes any traces of remaining membrane tissue. You might be able to tan a thin deer in a few days, but it would probably require a lot of extra work. Deer have more variability in thickness, with typically thicker necks and rumps than a goat skin, but they might tan faster just because the fiber structure is relatively loose.

      I have not used acorns much. I see no reason they shouldn’t work though. The caps can be good too. If it works, it works. I’m sure that there is a great deal of variation in tannin content among acorn species.

      Reply
  25. Sean

     /  March 18, 2015

    Hi Stevene,
    What are the signs that the hide is rotting? I have had a deer hide soaking in solution made from chipped douglas fir bark for about a month. I strengthened it twice, and now am starting with a whole new fresh batch of black walnut bark solution. Most of the hide appears to be tanning, though the color has not penetrated to the center. Some portions of the hide however, feel slimy and squishy and developed a some black mold (i think) on them. Is that rot? Can it be fixed or should I cut it out? I’m afraid the chipped douglas fir bark may have had too many sap sugars from needles that were mixed in. The black walnut solution appears to be stronger and more astringent. Thanks for your input,
    Sean

    Reply
    • I wouldn’t worry about the needles in the bark. If it’s strong enough, it shouldn’t hurt anything too much. Just guessing, but probably not something to lose any sleep over. I would finish the skin out just the way it is unless there are parts that are clearly rotten and weak, then maybe cut those out. That is a lot longer than you should need if the solution is strong and you are tending to it once in a while with stirring or scudding. I haven’t used black walnut bark. From the little I’ve seen of people using doug fir, it might be hard to get it very strong. You can still keep moving the skin from one solution to the next pretty fast, just using up what is in there. It doesn’t take that long for a fresh skin to use up a solution. If you can’t keep up, then you can’t keep up, but think in terms of shorter tanning times with thin skins and of keeping the solution strength up with frequent additions, or just moving the skin to a new fresh solution. Good luck with the black walnut bark. I don’t know much about using that.

      Reply
  26. I finally got around to reading this article. It is great and much appreciated. Bark tanning is on my long list of skills I need to acquire and this is an excellent start.

    Reply
    • Hi George; book coming soon, that’ll be an even better start. We virtually all make the same mistakes in barktanning. I’ve seen them over and over again. You probably have experience with buckskin. That will help. With that and this article, you’ll probably do okay first time around. Also, read all the comments here if you haven’t. Lots of good stuff in here from other people! And thanks for reblogging my skinning video. I got a lot of new hits and followers. Much appreciated!

      Reply
      • I’m looking forward to the book then. I’ve been around bark tanning and have done more brain tanning than I even want to admit. I just love the bark tanned stuff.

  27. yournextboldmove

     /  November 15, 2015

    Would you even start thick hides like cow in strong bark liquor? I’m tanning half a cowhide now, and I’m starting it with the third boiling of oak bark diluted 1:1 with water.

    Thank you for all of this information. It’s very helpful. I’ll definitely buy your book.

    Reply
    • I wouldn’t even consider that close to very strong. I basically wouldn’t consider even the second boiling really strong at this point, though it depends on so many circumstances. I’m starting to suspect that case hardening is more of a modern phenomenon when strong extracts became more common. I don’t think it used to be easy to make strong extracts, but later, they would run the same liquid through mulitple bark leaches and really bump it up. This just occurred to me recently and I haven’t ever read the literature with that thought in mind. But just thinking back, I’m not sure I’ve seen any references to case hardening in the really old literature.

      If you are actually boiling the bark, you get a lot out. the first pour should be very strong, but I’ve put pieces of skin into that with no ill effect and I have pretty quality bark here. It may depend on the type of tannin though and there are stronger materials out there for sure. I start in a second or third boil usually, with a little water as needed, but the minimum amount because you will be adding so much more liquid as you go along. combining 2 and 3 is probably fine. It gives you more liquid to start with, and still dilutes the second boiling if you’re concerned. I just stopped worrying about it at all basically. If anything at this point I like erring on the strong side. If I ever hit the wall, then I learn something, which is more important to me than any given piece of leather actually turning out. Anyway, it is not supposed to damage the skin permanently, more like slow the process, though it might affect the qualities of the leather I would think somewhat. But I wouldn’t know, because I’ve literally never seen it. I have plans for experiments to find that point with my oak bark where it is actually a problem, but haven’t got around to that yet. I need three of me. One just to do tanning and tanning experiments! Or at least some competent help/labor.

      Whatever the case, I like to scrape over the flesh side pretty soon in the tanning process, just after the outside is tanned.. It will open the hide out and make for more even and faster tanning.

      Reply
  28. Steven

     /  December 26, 2015

    I’ve made about 50 gal of red oak bark solution about 1 month ago did 3 boils and put into 5 gal buckets with lids, and yesterday went to get some tanning solution and its starting to get what looks like a slimy tannish gel chunks in it, has anyone else seen or heard of this? Can it be going bad? I have the 5 gal buckets in the house which is 70 80 degrees. I currently have a squirrel hide soaking in the solution now with the gel strained out and seems to be taking color fine. Was just wondering if the oak tan solution can go bad over time. Thanks for any help on this.

    Reply
    • I haven’t seen anything like that that I can recall. I tend not to make up extra solution too early anymore though. It can definitely go off in various ways, like mold and ropiness (slimy stringy). I have no idea how any of those specifically effect tanning or the tannins in the solution. I’m not sure what liquid concentration you’d have to make it in order for it to keep well. Most concentrate is in dry form. If possible, it is probably better to save the bark dry and make up solution as needed. I think you just need about 50 more squirrels and you can use up that 50 gallons! :)

      Reply
      • Steven

         /  October 4, 2016

        Thanks for the reply, I have forgotten I posted this question until now with hunting season opening again. Well I think your right about producing the solution as needed, I tanned 2 squirrel hides with hair on successfully, when the solution was fresh, then did a few more after the solution started to gel and get slimey and the mix had a real loud smell at this point, them squirrel hides did alright except for I was getting the same dark rich color as before and I did get some hair slipping. So I gave a buddy 20 gal or so of the 3 different strength solutions for a deer hide and after about a month of soaking it, the hide started to turn a greenish tint and stunk horrible and majority of hair slipped out, so he soaked it in ash water to save it and stripped the remaining hair off and made a drum out of his hide. So after he told me what happened I then took the remaining solution and did a deer hide as well to see what happens, I started out with a really high concentrate and kept adding new mixture for 2 weeks the color came out amazing but I did start to get a loud stink at this time with slight greenish tint on a small portion of the hide and I did lose some hair but I think that was my fault for over working the hide but no bald patches from slipping like my buddys. Also the flesh side got a little on the hard side probably because of the high concentrate I used from the get go. So this past weekend I dropped a red oak tree for fire wood and I plan on striping the bark and giving it another go this year but this time I’m going to do what you said and produce concentrate AS NEEDED LOL, and see what the out come is this time. But I believe after not to long storage, matter of weeks the concentrate deff. begins to degrade, just by the smell it had not to mention the thick gel chunkys in it. Again thanks for the reply. Ill let you know this years results as soon as I get started.

  29. Kelly Moody

     /  April 25, 2016

    Do you have any experience using coffee or tea in tanning? I have seen a finished tea-tanned hide done but not anything with coffee. I usually use hemlock, but I am at a craft school where there are buckets of tea thrown out daily and it is a way to experiment with using the waste. I started the hides I have with tanbark, then froze them for 6 months because I was traveling, and then pulled them out and started soaking them in black brews again while at this school (Penland School of Crafts in Western North Carolina). I know its probably weaker than the tanbark but I’m seeing how it goes. There are two soaking right now. One is small and looks pretty tan throughout when I cut a cross section. Skudding regularly and limed the hides last year when I started them. I’m taking a traditional book making class for 8 weeks and want to use my own leather with the books. People freak out here over my finished bark tanned hides. Because, its not exactly the kind of place where people do these kinds of primitive skills (blacksmithing, woodworking, pottery, sure), and the bookmakers who usually buy commercial leather are all very interested in bark tanned hides. Its an interesting peak into a world where people are disconnected from that part of the process even though learning craft skills is about the process.

    Reply
    • Kelly Moody

       /  April 25, 2016

      black brews- I mean ‘black tea brews’

      Reply
    • I don’t, but I have some thoughts for sure. both obviously have some of the tannin removed already. If they were strong enough to easily tan hides in the first place, they probably aren’t now. Most people already make liquors much too weak and leave them too weak. I would make tea with the same water using multiple batches of leaves. At least two batches if not 3 or 4 to get something that is reasonably concentrated. So, steep in very hot water (125 degrees? I only say that because some tannins are destroyed by boiling and I don’t know what kind are in tea) for hours, then strain and add another batch of leaves. Just barely cover the leaves. You can judge strength by tanning skins in it. Look at the liquor before you start and try to remember what it looks like and how much it changes after hides are put in. The hides will use up the tannin very fast at first and you should be strengthening the liquor within a day, or leave for several days until the tannin is spent, then use a new batch of tan to replace it. Just because there is color, doesn’t mean there is tannin.

      Goat skin used to be used a lot for bookbinding. It should be pretty easy to tan those for that purpose. They tan really fast. Once tanning starts, it shouldn’t be taking you very long to finish goat skins, like a week or two usually if the liquors are kept up and it is manipulated or scraped over once in a while. We do goats in just a few days in classes.

      To me making your own supplies for crafts and art is the holy grail. I think more people will be doing it. They just have to be shown how possible it is.

      Reply
      • Kelly Moody

         /  April 27, 2016

        What my friend said she did because she worked at a coffee shop and wanted to experiment with their generic iced tea: was to take the ‘unbrewed’ bags, the fat ones for restaurants, and then boil them for hours and use that brew, as well as the throw away tea from the tea counter. I haven’t thought of the tannins in the tea possibly being destroyed by boiling. What I’ve been doing is collecting the throw away tea from the tea counter here at the school because they toss it every single meal and then throwing the tea in my hide bucket. I’m always trying to think of ways to close that loop or eliminate waste. I stopped using coffee because I felt like it was really dying the hides and I was worried it would trick me into thinking they were further along than they actually were. This week, another person here who has taken to the process has helped me collect untreated douglas fir shaving from the woodworking studio and we have boiled that along with heating up unbrewed tea bags like my friend Miranda did just to get some more strength in there. Since the hides were already halfway done from a strong and attentive cycle with tanbark solutions, I thought i’d give this a try. Also, since I’m busy with the classes, and don’t have a ton of time to go out with the draw knife and collect while i’m here, this was a way to see if I could do it another way. Although it is probably subpar because the tea is not strong in the quick cafe brew. I’ll try the multiple brewing concentration method. One hide ‘seems’ done- it is a small thin baby deer and when skudding it, it just feels saturated and tanned through. The cross section is dark, but I’m not sure if the coffee is the reason for that. I’ve always had trouble knowing ‘for sure’ if a hide is done. The other hide is an adult doe and is obviously not done, and the cross section still has a fleshy color in the middle. We also threw a roadkill blacksnake skin in we picked up the other day- it was the idea of another student here who has never done this before. I have actually never tanned a fish or snake so we’ll see how that goes. It seems thin and like it would go quickly given strong brew. If it comes down to it, we’ll just go cut one of the young dying hemlock trees around here (sadly, many have the wooly adelgid) and pump up the brew. Since I’m not on the west coast anymore I can’t use any more of the tanbark, which I’ve really liked using in the past. And, the sumac here hasn’t leafed out yet, which I’ve also used.

        My teacher, who has a MFA in bookbinding (crazy that exists) and mainly focuses on art and ecology themes in his work, offered to buy one of my kind of junky brain tanned hides full of holes that had yet to be smoked to use it in a book project. He said that tons of bookbinding professional type folks- would be especially interested in the ‘natural leather/bark tan’. I’m into it to a degree, more on the lines of showing other artists that you can make your own easily-, but something about selling or trading that leather to someone who is planning to make a thousand dollar book.. is a weird thing for me. There is all the ‘equipment’ here to do fancy leather bookbinding, we’ll see if I’ll get to it before I’m done here.

        Do you think pig skins would be good for book binding? I have access to a bunch of those and haven’t worked with them before.

      • I think you might be right about the coffee color masquerading as tan, but I don’t really know. I know Benjamin Pixie has used coffee grounds some. It’s on my list of things to try. Look for blow downs right now. I know you guys have wicked spring storms. One good oak tree or even a big limb could yield a lot of easily peeled bark at this time of year. You might also check with firewood cutters. They often pile up bark and just burn it. Well, those thousand dollar books might also keep the craft of bark tanning alive. I know it’s ironic though. I have trouble with that stuff too. Pig is highly variable in thickness. That is actually an issue with any skin for bookbinding I’m sure. goats tend to be a little more even. I believe sheep and calf have been used a lot too, but I’m not sure. Hides used to be thinned by hand according to what they were to be used for using a special knife called a curriers knife. Cool stuff.

        >

  30. This is definitely one of the best barktan articles on the web. Thanks!

    Reply
    • Thanks, I agree :) I feel like this approach is just about the most useful since I’ve seen these mistakes over and over in myself and others. Absorbing these problems and understanding them should be able to save the vast majority of mistakes made in learning to veg tan. I refer people to it constantly and will probably do a video version soon or maybe just continue to treat each problem in turn in it’s own video. I don’t really keep up this blog anymore. Everything is over at http://www.skillcult.com including all articles from this blog, or on http://www.youtube.com/skillcult Thanks for your comment.

      Reply
  31. Steven

     /  October 4, 2016

    I just read the rest of the comments, If your the SKILLCULT guy on youtube, your channel is one of the best Ive found with butt loads of good explained info, Keep up the Awesome work, you got true talent and drive.

    Reply
  1. Turkeysong, the Year in Pictures 2013 Late Winter and Spring « Turkeysong

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: