When my wife and I decided to make soap, our first thought was to use commercially produced lye crystals. For our second batch, however, we decided to try to make it the way they did in the past. So we decided to make our own lye for use in the process. And, it turns out making your own lye at home is not difficult at all. WARNING: Lye is very caustic! Use extreme caution when making it or using it for any purpose.
STUFF YOU NEED:
To make lye, you need a few simple pieces of equipment, and only two easily-obtained ingredients. We simply used a spare terra cotta flower pot lined with a scrap of old burlap bag to keep the ashes from simply draining out the hole in the bottom when the rainwater was put in. We then set up ten red bricks on the ground in two stacks a foot apart and set a spare grill grate across this. We then centered the terra cotta pot on the grate. Underneath the pot, on the ground below the grate, we placed an old steel coffee can to collect the lye. Be sure you use steel or glass, as the lye will eat through pretty much anything else.
GETTING THE ASH:
It is important that the ash you use for making lye is from a hardwood such as oak or walnut. Do not use softwoods like pine because the sap contains resins that will not make good lye. We used oak and burned it in our charcoal grill. We then allowed the embers to die naturally, burning completely and leaving a nice collection of nearly white ashes. From what I can tell through experimentation and through my research, the type of hardwood you use does not really make a noticeable difference in the quality of lye produced.
GETTING THE WATER:
The best water to use for making lye is rainwater. We live in an area that gets regular rain so collecting rainwater is not difficult. Rainwater is considered great because first of all it is free. All you have to do is put out containers to collect it. The other reason rainwater is used is because it has no chemical additives such as chlorine and fluoride found in regular tap water. Of course you can leave a pan of tap water on the counter for 24 hours for these chemicals to dissipate from the water and it should work just as well. Finally, another option is to use distilled water, which is available at most stores, or set up a distiller to make your own distilled water.
To make our lye, we packed the terra cotta pot with the liner about ¾ full with the hardwood ash. Then we poured the rainwater into the pot until it was nearly full. As it drained through the ash, we poured in more water until we had the amount of lye water we needed.
USES FOR LYE:
The lye we produced using this method was used in soap-making. Lye is also used commercially in oven cleaners and in products made for unclogging plugged drains. Food-grade lye, which must adhere to very strict standards, is used in several different food products, such as lutefisk and canned mandarin oranges, as well in the production of hominy, and in several different types of oriental foods. The lye produced using this method is NOT food-grade lye!
If you are making the lye a few days before you start your project, it can be stored in glass containers with tight fitting lids, such as a canning jar. If you are keeping it for a longer period of time, it can be left outside, open to the air to allow the liquid to evaporate, leaving lye crystals, after which it can be stored in the same manner as the liquid lye. Another method of turning the liquid into crystals is to boil it outside until the liquid has evaporated.
Lye is very caustic! Use extreme caution when making it or using it for any purpose.