Different Types of Molds For Cold Process Soap Making
The most popular is the wooden log soap mold. This type of mold is constructed using a hard wood, like pine or poplar. It is formed into the shape of a long rectangular box with a removable lid, like a shoe box. The box is then lined using a release, this can be a plastic-coated paper or a custom silicone mold. This allows the soap to be removed easily after it has hardened. After the box is lined, the saponified soap mixture is poured into the log mold and allowed to sit overnight. Once hardened, the soap resembles a loaf of bread, and can then be cut into 1' thick bars to cure for several more weeks.
Another type of wooden soap mold is the slab mold. This is also made from hard wood, and is shaped more like a flat rectangle with dividers inside. The size of the interior dividers determines the size of the soap bar. Most slab molds will hold 20-30 bars of soap at a time. You can also use slab molds without interior dividers, and later cut the bars, or use cookie cutters to create fun shapes.
Soap molds are also available constructed from silicone materials. The benefit of silicone molds is you do not have to line the mold before pouring the soap mixture, as the silicone acts like the release agent itself. Although this may seem quicker and easier to do, after awhile the silicone does break down, absorb odors and colors and should be replaced.