Suppose I have a 5 mm strong plate of say 200×200 mm footprint. Which of the following materials would make it stiffest? [list type=square] [*]WSF: Shapeways' White Strong & Flexible (Nylon) [*]ABS: 3D printed (FDM) on a Stratasys machine [*]Acrylic glass: laser cut [/list]My assumption: Acrylic glass (stiffest) > ABS > WSF (softest)
On plastruct.com, I found an article about properties of ABS, acrylic, and various other plastics. They write: "Acrylic is the most rigid and brittle of these plastics." For comparison of ABS and WSF, I have ordered a set of FDM printed ABS parts from fabberhouse in Germany. The nice thing is that they print in solid black and other colors.
Yesterday, I received my order. It's hard to tell from the parts, which are quite small, but ABS seems to be more rigid than WSF. At the same time ABS is certainly more brittle: When I bend a thin part it breaks quickly. WSF, on the other hand, can sustain quite a lot of torture before it breaks. Still, FDM printed ABS is a great material, and I consider using it for a mechanical design.