Geeetech i3 Underbed ToolBox

My desktop is constantly short of space and gets cluttered by tools in a millisecond, so I'm struggling to keep it tidy.

This tools holder is designed to fit under the heated bed of my Geeetech i3 and should be able to host all those tools and items I keep around, like:

* Allen keys
* screwdrivers
* wrench
* digital caliper
* pliers
* screws, washers and nuts
* nozzles and throats
* nozzle cleaning drills
* etc...

All walls are `0.8mm` thick, to match with a `0.4mm` nozzle (which I use) so that 2 perimeters fit perfectly: I hope this provides enough structure to hold everything while saving on filament and print time.

The box has 4 slots for small zip ties so it can be fixed to the M10 rods of the frame and so avoid any interference with the Y belt when you move the frame: tension the zip ties so that the toolbox remains solid with the frame.

I also designed a dedicated nozzles insert which also acts as a separator for one of the small compartments: it a