@ LrnFzx : wow, your suitcase bikes are pretty cools ! Are they rigid enough compared to a "not cut bike" ? Do you plan to make a folding bike one day ?

Here is my first build (and, eeeeh... my practice for welding )

My super cheap cargo bike (~100€, including all parts). Nice to ride, but a "little" tank with 32kg and 2,60m long. 90x60cm of "cargo" space, already tested with ~80kg of wood but I wouldn't put more than 70kg in use.
The donnor bike was an old supermarket MTB, steel tubes and profiles are recycling or from scrapyard, the box is made with palette wood (burned + linseed oil + walnut broth).
Welded with a MMA inverter, no jig (), a lot of grinder an files, about ~150 hours of work.

I'm already thinking about the next: a trike, that I'll modify as a velomobile. But this time with a jig an better welds.