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, a German electrical switch manufacturer, wanted to save time and cost in prototyping a new switch comprising multiple plastic parts. Since the assembled switch had to pass an electrostatic discharge (ESD) test, it had to be made of the same materials as the final part. What’s more, the newly designed parts required precise dimensions to permit snap-fit assembly.

Berker produced a series of 3D printed injection molds using Digital ABS plastic deposited by a Connex 3D printer from Stratasys Ltd., Minneapolis. This printer uses PolyJet ink-jet printing technology. The plastic molds were used to mold functional prototypes in ASA, PC, and TPE, allowing Berker to try out different solutions at the same time. These materials were molded at temperatures from 225 to 300 C (437-572 F) and pressures of 5945 to 8512 psi, with cycle times of 100 to 200 sec. 3D-printed molds were produced in 3-4 days at a cost of 1000 to 1200 Euros, vs. 6000-7000 € and 3-4 weeks for machined aluminum molds. Prototyping with 3D printed plastic molds thus reportedly saved 83% in cost and 85% in time compared with aluminum molds. Berker said the plastic molds were good for 25 to 50 parts.