Silicones (not to be confused with the semiconducting element silicon) are a group of synthetic polymers with various properties. Some of these, e.g. heat resistance and flexibility, are very desirable in a product or prototype.
|Suggested Tools:||caulking gun|
Silicone sealant is usually pressed out of cartridges with a caulking gun and hardens upon air contact. A common workshop trick is to seal the cartridge with an old wood screw after using to prevent the formation of a clog in the nozzle.
For a nice finish, lay down an even bead with the caulking gun and spray some water or a water/dish soap mixture on it. Smoothen the sealant with a light pass of a finger, popsicle stick or a special little plastic card for this purpose. Instead of spraying, you can also just wet your finger/tool!
If you've made a mistake, better be quick - water can help very early on, when the sealant is partially dried there are special silicone removing agents, and when it's dry you can't do much except scrape/rub/pull it off with a lot of patience...
Molding silicone is used to create a negative mold from (almost) any template. We have documented the procedure here.
There are different types, food safe silicone is more expensive. If you want to make non-food molds, e.g. for candles, consider using the cheaper silicone.