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The process of tanning hides cleans them and preserves them so they can be used for many things. Traditional cultures did not waste any part of the animals they killed. Hides became clothing, tents, storage containers, and more.
You can tan a hide to make leather or buckskin. Leather undergoes a different chemical process and comes out tougher.
I'm more familiar with the procedure for making buckskin. On this page there are photos of my husband working on a hide for a demonstration during an event at Jefferson Patterson Park.
This is just a basic outline. If you really want to try it, we highly recommend the book Deerskins into Buckskins: How to Tan with Brains, Soap or Eggs; 2nd Edition which has lots of details and helpful hints.
The first step is to scrape the hide clean of all remaining flesh and hair. There are two ways to do this, the dry scrape method and the wet scrape method.
The next step is dressing the hide, which is penetrating it with fats for preservation.
Traditional hide tanning used the animal brain. Most animals have exactly the right amount of brains to tan their hide.
Egg yolks or whole eggs can be used as a substitute if you don't have any brains.
The skin must then be stretched taught during the drying process so that it dries flat and stays soft instead of becoming stiff.
As you can see, my husband likes to actively work to tug and stretch the hide as it dries. You can use a tree trunk or post to help you or for even more fun, get a group of people to grab the edges and pull.
Finally, the soft, stretched hide should be smoked to make it water repellent. A smoked hide can withstand rain and rinses in cold water. Then you can use the buckskin to make whatever you want!