EPS Foam widely used as Helmet Mold material, it light, inexpensive and water-resistant.
EPS foam is perhaps the most common in everyday life: this white foam can be seen in cups for hot beverages, refrigerators, insulation, packaging, etc. The foam plastic consists of 96 – 98% air and 2-4% polystyrene. Granules are heated with steam in such a way that they are rapidly expanding (foaming) and forming a low-density block (in a special form).
Expanded polystyrene – EPS
Expanded polystyrene - CNC foam cutting example
EPS foam material is inexpensive and light – usually weighing 15-30 kg per cubic meter. Expanded polystyrene does not lose its fundamental properties with time and can be completely recycled and reused.
There are two types of polystyrene foam best suited for processing with the Hot wire foam cutters and Hot knife cutters: extruded polystyrene (XPS foam), and expanded polystyrene (EPS foam). Although both types of insulation are comprised of polystyrene, the two types of manufacturing processes produce finished products with very different performance properties. XPS is manufactured in a continuous extrusion process that produces a homogeneous closed cell crossed section, whereas EPS is manufactured by expanding spherical beads in a mold, using heat and pressure to fuse the beads together.