HO Stelcon / industrial plate

H0 Scaled 'Stelcon plate', also known as industrial or concrete plates. It's a common and relative cheap way to pave larger areas of industrial or agricultural areas.

These plates are made out of concrete, with a metal frame on the outside. In the middle two holes are present, used for laying the plates with a crane hook.

I've created two designs. The design that's printed in one piece is tested with a FDM printer. The other design, that allows for the outer metal frame to be painted separately, isn't tested and could properly only be printed with a resin-printer.