This wheel has been able to easily replace my broken wheel.
This new version just need bearing (for ex 623ZZ) and a small metal rod to block the wheel.
It works really well now.
I printed it with PLA now, it is as you know easier, and no pb for the strenght (more than 2 years now with the same wheels).
The version file V2 is stronger than the first one.
Just add two 623ZZ bearing per wheel, and a curved metal rod to block the final little piece, and you're done for a while.