This is a 20 ton Macaw Bogie Bolster wagon scaled for 00 gauge model railways and optimised for FFD printing. It is designed to be relatively easy to make and need minimal support.
Use quality PLA+ for best results, using cheap filament means you are more likely to need to fettle parts to get free movement.
A light tree support setting is recommended. I suggest painting before assembly. Use four commercial 00 wheelsets, 11mm diameter wheels recommended. The vertical stanchions are 1mm polystyrene rod.
I recommend printing using the combined STL which includes a few extra buffer pads and pivot caps.
STL (Stereolithography, filesize: 75.1 MB)