Concretium "river & sewer tiles"

update 17.04.2025: Revised versions of the parts "sewer_wall_bridge_railing" with a thinner groove on the bottom have been added. They should print cleaner then the original part. The groove itself is just a visual indicator where to glue railing and floor and no valid connection point. You can find the updates parts: "sewer_wall_bridge_railing_L-M_rev_250417_final.stl", "sewer_wall_bridge_railing_L-M_250417_final.stl" and "sewer_wall_bridge_railing_x2_L_250417_final.stl" in the object parts fol