Trailer with swivel base

It was about time for a new trailer. I've been wanting to design one with a bogie for a while now, so I sat down and designed one.

The trailer is modular (with additional holes in the frame) so that different superstructures can be attached to it. In addition, the trailer coupling is equipped with 2 joints so that it fits all tractors.

The superstructures available so far are
Wooden stanchions and holders for a plate (for hay) are available. More will follow.

What is needed:
- M3x10, 16, 18 and 20 bolts
- one ball bearing 18x12x4 (for the bogie)
- 4 ball bearings 8x12x3.5 (for the wheels)

For the hay wagon I recommend cutting 3mm wooden boards to size (best to measure when the superstructure is on the frame).

The building instructions can be seen in the pictures, additionally the axles, axle mounts and the frame are labeled.

UPDATE:

there was a mistake with the upload, the Axle_support_F_L was wrong, now there is the correct file.