Brain tanning is one of the oldest and most rewarding methods of turning a raw animal hide into soft, durable, washable leather. Unlike modern chemical tanning, this process uses only the oils found in the animal's brain — a substance every animal produces in just the right quantity to tan its own hide.
Why brain tanning?
There are many ways to tan a hide. Chrome tanning dominates the modern leather industry, but it relies on heavy metals and industrial chemistry. Vegetable tanning with bark produces beautiful, firm leather — ideal for belts, bags, and tool sheaths. But when you want buckskin — soft, stretchy, breathable leather for clothing, pouches, and wraps — brain tanning is unmatched.
The resulting leather is:
- Incredibly soft and supple
- Washable (it can get wet and dry soft again, if smoked)
- Free from chemicals
- Connected to thousands of years of human tradition
The process
The full brain-tanning process takes several days of hands-on work. Here is a simplified overview of the stages:
1. Fleshing
The fresh hide is draped over a beam and scraped clean of all remaining flesh, fat, and membrane. This takes patience and a sharp fleshing knife.
2. Bucking (optional)
Soaking the hide in a wood-ash lye solution loosens the grain and hair. After bucking, the hair is scraped off and the grain layer is removed, leaving the inner hide.
3. Braining
The brain is mixed with warm water into a slurry and worked thoroughly into the hide. The lecithin in the brain coats and lubricates the fibres. The hide is wrung, re-brained, and wrung again — this step may be repeated several times.
4. Stretching and softening
As the hide dries, it must be continuously pulled, stretched, and worked by hand (or on a frame) to keep the fibres separated. If the hide dries stiff, it hasn't been worked enough. This is the most labour-intensive stage.
5. Smoking
Finally, the soft hide is sewn into a bag shape and hung over a smoky fire of punky wood. The smoke deposits aldehydes into the fibres, which lock in the softness even after the leather gets wet. Without smoking, brain-tanned leather would dry stiff after washing.
A living tradition
Brain tanning isn't just a technique — it's a way of relating to the materials around us. Every hide is different. The process demands attention, physical effort, and respect for the animal. The reward is a piece of leather that carries a story, and that will last for years.