A simple well car I designed for G scale. You'll need two prints of the half-frame, one print of the well, and 10 copies of the half-beams to create 5 full H beams that support the well under the car.

The dual wheel bogie I used can be downloaded here: https://www.thingiverse.com/thing:3024808

The couplers can be downloaded here:
https://www.thingiverse.com/thing:1974185

The brake wheel I used is from here:
https://www.thingiverse.com/thing:400368

Creality

Ender 3

No

No

0.32mm

no