Vacuum forming is another variation of thermoforming but it deserves a separate write up of its own given its unique problem-solving ability. Similar to drape forming, vacuum forming starts with heating the entire piece of material in a convection oven. Once at a malleable temperature, the sheet is removed from the oven and placed over a mold. It is here, though, where the similarities with drape forming end. Next with vacuum forming, a hydraulic press pushes the mold into the heated sheet stretching the soft material over the edges of the mold and creating a seal. Once a seal is created, vacuum suction is applied through pores in the actual mold, this vacuum physically pulls and stretched the hot material into any cavities and over any protrusions of the mold. Once cooled the piece retains the shape of the mold in incredible detail. The advantage to vacuum forming is the incredible fidelity achieved with respect to the original mold even in cases with very contoured and complicated shapes. Something that would never be achievable with simple drape forming. Think bathtub liners, or blister packs for product packaging. Our vacuum forming machine has a 4ft x 8ft bed and a 2ft draw depth.
