Manufacturing parts with multiple materials is possible thanks to the overmolding process, which is a two-step procedure, either manual for small production runs or automated for large runs. It starts with thermoplastic injection forming the rigid substrate, followed by a second shot - generally thinner and more pliable - injected in, on, or around the substrate. As the materials cool down, they join together and form a durable part, bonded together by either chemical or mechanical means, depending on the materials and the design.

With the multiple molding steps, Honpe is able to process on-demand vacuum casting prototypes with bicolor, tricolor, and more.