In this moldmaking instructional video, Milo shows how you can make your own mold knife using readily available, affordable blades. Mold knives create a key in your mold when you cut the mold, which helps the mold register and align properly when casting resin, rubber, foam, or other materials. A mold that registers well will give the least amount of flashing when making props, sculptures, or other types of pieces. For more info about silicone and other rubber for moldmaking, visit: https://www.