A few months ago I started experimenting with tanning deerskin using oak bark. Here’s what I’ve done so far…
NB – This post is not for my squeamish, faint-hearted or vegans friends!
The Skin and Defleshing
Once the inside of the skin (flesh side) has been scraped this then gets put in a bucket of water and wood ash (about 2 parts water to 1 part wood ash). This “lime” solution starts to work at the hair follicles to break them down so the fur can be removed. (I’m removing the fur now because roe deer is well known for not wanting to keep its fur after being tanned, apparently.)
Another fascinating factoid that my tanner-friend Peter said is that it’s not actually the lime solution that does the job but microbial action that lives in this solution. So it’s best to keep this solution for future use as it will get stronger as the bacteria grows.
This stays soaking for 2 or 3 weeks.
Oak Bark Peeling
Meanwhile, make sure it’s spring time when the sap is rising and find some oak that needs felling (check for nesting birds). The bark seems to peel best when it’s been sunny and warm, and a big moon helps to draw the sap up too.
A wonderful byproduct of this process is that you end up with a load of beautiful, white oak that can be used for all sorts of constructions. I turned the wiggly branches into display-hangers for showing off some of my leather products.
Making the Tanning Liquor
It’s best to make sure the bark, once harvested, doesn’t get too wet as the water-soluble tannins will leach away. You want to keep as much of the tannins in the bark ready to be used. We (Coppice Association North West) gather oak bark at this time of year, dry it out and then send it to Bakers tannery in Devon – the last remaining commercial oak bark tannery in the UK.
The picture below shows some oak bark harvested last year and dried out. I’m not sure if it makes a difference whether to use dried or fresh bark…
After chopping the bark up into small pieces (the smaller the better) it’s into the bucket with it, followed by some rain water.
The proportions of bark to water has been tricky to find out, so I’m experimenting. The important thing is that the first solution needs to be relatively weak, followed by progressively stronger solutions. This is so that the outer surface of the skin doesn’t get overly tanned first, preventing the tanning solution from penetrating the inner section of skin. This is more important for thick skins, such as cowhide, less so for thin deerskin. So this is what I did:
1st weak solution = 1 part bark to 4 parts water
2nd stronger solution = 1 part bark to 2 parts water
These buckets are then put to one side to let the liquor brew so they’re ready for after the de-hairing…
After about 2 weeks in the liming solution the skin is removed and placed back on the log, fur-side up. If the solution has done its job then the fur should easily come away, bringing a very thin white membrane with it. I use the same scraper as I used for defleshing.
I’ve found with the two skins I’ve worked so far the fur remains stuck on in some places. On the first skin I decided to proceed with tanning, regardless of the fur. The fur eventually came off anyway but has left the skin with a lighter colour where the tanning solution didn’t make enough contact with the skin. For the second skin I decided to put it back in the liming solution for another week or two to try and loosen the remaining fur.
Once all the fur has been removed the skin needs rinsing again.
So far I have one skin that has been in the weak tanning solution for 2 months and has now been in the stronger solution for 2 weeks. The bark is giving it a dark colour – beautiful. The second skin is still in the lime solution trying to loosen the hair.
I’ll update this post with more news as it happens.