A Mold is a device constructed to allow the copying of a prototype piece.
Flexible Vs. RigidEdit
Box molds rely on a box or other simple container to hold mold material in place. Box molds require minimal effort to construct, but may be wasteful of mold material. Since information is lost anywhere the prototype piece is touching the box, box molds are most commonly used on pieces with at least one flat side that may lie on the base of the container.
Mold boxes may be constructed from any rigid material able to withstand the force of the mold material. Lightweight molds, like small silicone molds may be walled with simple card stock secured to a table with hot-glue. Heavier molds, like large plaster molds may require a custom wooden box secured with heavy duty screws.
A glove mold is a relatively thin, flexible mold that is created by brushing mold rubber onto a piece. Glove molds are intended to be turned completely inside-out during unmolding, and are thus able to function despite extreme undercuts. This allows the production of seamless pieces.
Glove molds may only be used on "one-planar" surfaces. Stresses placed on repeated castings of a mold can make it weaken or tear. As with most flexible molds, a mother mold is required to support the shape.