Using homemade hide tanning solutions will give you more control over the leather you need for your projects. There are many different tanning solutions. Since each process produces a different result depending on which type of hide is used, you will need to experiment at first to determine the look and feel you want to achieve. Once you become accustomed to each process, your finished results will be more consistent.
Mix the solution for bark tanning hides two to three weeks before you plan on tanning. Grind 13.6 to 18.1kg. hemlock bark in a grist or hammer mill using a fine screen. You may also use oak. Pour the ground bark into a 60 gallon wooden barrel or plastic container Pour 20 gallons of hot water over the bark, and stir it thoroughly. Allow the mixture to stand for two to three weeks, stirring it occasionally. This makes enough solution for one large hide, or several small hides.
Mix the solution for chrome tanning hides at least two days before you plan on tanning. Add 1 0.340kg. of sodium carbonate crystals and 1.36kg. of salt to 1 1/2 gallons of warm, soft water in a wooden barrel or plastic container. Stir until dissolved. In a second wooden barrel or plastic container, dissolve 2.72kg. of chromium potassium sulphate crystals in 4 1/2 gallons of cold water. Mix the two solutions together by slowly pouring the first solution into the second solution while stirring constantly.
Mix the solution for salt-alum tanning on the same day you plan on tanning. Mix 0.454kg. of alum in a wooden or plastic container containing 1 gallon of warm, soft water, stirring until the alum dissolves. In a second, similar container, mix 1.13kg. of salt with 4 gallons of warm, soft water. Add the salt solution to the alum solution, pouring slowly while stirring constantly. Let the mixture cool before beginning the tanning process.
Mix the first solution for alum-carbolic acid tanning on the day you begin the tanning process and the second solution the next day. Mix a solution of 1 1/2 tbsp of carbonic acid crystals for each gallon of water needed to cover whatever hide you choose to tan. Soak the hide overnight. The following day, mix a solution of 0.227kg. of salt, 0.113kg. of alum and 14.2gr. of carbolic acid crystals for each gallon of warm, soft water needed to cover your hide, stirring until ingredients are dissolved. Let the solution cool, then remove the hide from the first solution and soak it in the second until it is tanned completely. You will know the hide is done when the colour is the same all the way through; just clip a small piece off the edge to check.
Mix the solution for sulphuric acid tanning on the same day you begin the tanning process. Fill a wooden barrel or plastic container with enough water to cover your hide. Stir in 0.227kg. of salt for each gallon of water used until completely dissolved, then carefully stir in 14.8ml. of sulphuric acid for each gallon of water used. Let the solution cool before submerging the hide.
Mix the solution for acid oil tanning on the same day you plan on tanning. Mix 0.113kg. of salt with 1/2 gallon of warm, soft water in a wooden or plastic container. Let the solution cool before very carefully pouring in 7.39ml. of sulphuric acid while stirring constantly. Use a paintbrush to apply the solution to the flesh side of your hide. Next, sprinkle a layer of sawdust over the side of the hide with the solution on it. Cover the hide with plastic and let it sit for 8 to 12 hours. Scrape off the remaining sawdust. Combine one part of neat's foot oil to an equal part of lukewarm water and apply it to the hide. Stretch the hide on a hide stretcher, or tacked to a wall until it is dry. Mix 11/2 tbsp carbolic acid crystals with 1 gallon warm, soft water until dissolved and dampen the hide with the mixture. Roll the hide up tightly and let it sit 24 hours before continuing the tanning process.
Do not use metal utensils or containers to avoid chemical reactions.