Particle foaming for real
The molded parts for the Floppy, POLLA and Varii projects were foamed at Kurtz Ersa in Kreuzwertheim (Bavaria) using Wave Foamer. The other projects LAR, minus20 and PackVac, on the other hand, were produced at the Fraunhofer ICT in Pfinztal near Karlsruhe. For both partners, using the mold materials plaster, ABS, polycarbonate or plywood was largely new. The knowledge gained benefited everyone involved. For example, the moisture present in veneer plywood or plaster is problematic and led to such strong heating in Floppy that ETPU turned back into TPU in direct contact with the mold and stuck to the mold.
Surprisingly, the mold made of ABS worked better than expected with Varii. POLLA and Varii also worked with a special compressed air setup to achieve better results with EPP.
Various molds were also placed in a wave former at the Fraunhofer ICT. The students experienced how their own tool shapes affected the magnetic field, whether the tools withstood the compression and what effects their deformation had on the molded parts. Another group of students gained an insight into particle production and had the opportunity to produce their own non-spherical particles.
& Simon Höfer