Primitive Soap from Wood Ashes

Wood ashes have been used for centuries as a source of lye in the soap making process. When lye derived from wood ashes is mixed with fats or oils a chemical action takes place to produce what we call soap. This is a simple process to use on treks & immersion events when carrying excess gear or non-period supplies may be problematic. It also makes for a great demonstration for the public. 

Ashes from hardwood trees are better for making wood ash “soap” than softwood ashes.  The wood ashes used to wash your eating gear must not contain residue from plastic, food, or other trash that was burned in the fire, as they could be toxic.

The lye from wood ashes dries hands if left on for a period of time;  be sure to rinse your hands in clean water after scrubbing your gear.  Similarly, do not use wood ashes to wash your body or any gear which cannot withstand harsh soaps.

Let the fire burn down to the point where you can easily extract wood ashes. Select the greasiest pot you want to clean.  If the food residue is not very greasy you can help the soap making process by adding a small amount of fat or oil into the pot.  Butter, olive oil, animal fat, etc. are all good. Just a few drops are enough.

Add a few cups of ashes into the pot; any bits of charcoal mixed in with the wood ash will aid in scouring. Add enough hot water to the wood ashes in the pot to make a paste.  The hot water will pull potassium salts from the wood ashes, which will then mix with the fats or oils in the food residue creating the soap.  

When the water & wood ash paste is cool enough to handle, smear it all over your cooking gear & mess kit.  Let it set for several minutes before scrubbing your cooking gear & mess kit clean. Rinse with water & let dry. Be careful not to use too much of the paste or let it sit too long on your mess gear; strong soap will take the seasoning off of cast iron.