Sheet, rod and tube in acrylic materials are available in both extruded and cast grades, the selection of which should be determined by the quality level desired when compared to cost considerations. When cast acrylic materials are manufactured they are manufactured from raw monomer which is cast or poured into molds. Once cured, the material is often ground and then repolished to finished dimensions. Casting is the more expensive of the two processes, but yields a better quality product.
Extruded acrylic materials, on the other hand, are manufactured by pushing acrylic pellets through a highly polished extrusion die to produce a finished product. Die marks and other slight imperfections may make extruded acrylic sheet, rod, and tube somewhat less desirable for critical applications. The process is less expensive however, and the quality is perfectly acceptable for most applications.