Simple, Fun Ideas for Making Soap With Lye

To make soap, you only need three basic ingredients: lye, distilled water, and oil—olive oil, coconut oil or shea butter work. With shea butter and coconut oil, you need to melt them first. In the beginning, be precise and follow the ratios properly until you get a feel for it. Finally, if you want to incorporate colors, make sure they are good for use in soap.

The smell from fragrance oils is wonderful, but they affect saponification—the chemical process behind making soap. Depending on which essential oil you use, saponification will either slow down or speed up, making the end-product a mess. Be sure of the fragrance you want to add and use a small amount to understand how it works for your recipe.

There are a few required tools that you need to assemble. Because you are dealing with lye, which burns through the skin, goggles and gloves are mandatory. Should it make contact with your skin, have some vinegar handy to neutralize it. Use a container that can tolerate heat for the lye, a spatula, a stick mixer, and your favorite silicone mold tray.

Add the lye to the water and stir. The mixture will get hot and produce a pungent smoke. Stir until it becomes a clearer liquid that is slightly cloudy. Add the lye to the liquid oil and mix it until it achieves trace—a creamy liquid coating the mixer, and when it drips, it bounces a bit as it hits the liquid surface.

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At this point, add the color first, gently stirring it in. Then add the fragrance. If you are dealing with an essential oil, measure it properly so you find that nice balance. If you’re adding ingredients like rose leaves and mint, fold those in. You want to be quick, as the soap will thicken the longer it's out in open air.

Get your silicone mold ready and pour the mixture in, scraping the batter out with the spatula. You can put the mold in an old cardboard box, seal it as best as you can, and cover it with a towel to help with insulation for the next 24 hours. Remember to keep it in a dry spot and out of sunlight.

After a day, you can take a look at the first stage. The soap should be hard and molded nicely. If you had a mold tray with multiple compartments, just pop out each bar. At this point, its consistency is like cheddar cheese, so it will be easy to slice. While it looks hard, the soap isn't completely dry and needs additional time. The final step is to complete the saponification process by curing it for four to six weeks. Find a spot where they won’t be disturbed, place each bar on wax paper and cover them with more wax paper to prevent dust from accumulating.

Lye is an alkali that comes in two forms: potassium hydroxide and sodium hydroxide. Potassium hydroxide makes soap more water-soluble, but sodium hydroxide is more common. Lye helps the water and oil mix homogeneously, so it’s an essential soap ingredient. However, it eats through organic material, requiring that you protect yourself and keep it away from children. If you don't want to handle the chemical or don’t have ready access to it, there is another alternative.

You can get a batch of melt-and-pour soap. These are premade starters with lye, so you don’t have to handle the caustic material yourself. These starters are made from shea butter, olive oil, glycerin, or some other combination. All you need to do is cut the starters in cubes, melt them down in a stainless steel pot set on simmer, and add your colors and fragrances to the cooled mixture. This is the simplest way to create your own custom soap.

If you like a little more lather in your soap, you can add castor oil to your recipe. By itself, it creates a brittle soap that's also a nice shampoo. The benefit is that the skin absorbs it easily and uses it to maintain a nice moisture balance. Castor oil is sticky, so you need to use the spatula to get all of it. Adding castor oil, however, speeds up the emulsification process, so plan accordingly.