
The larger part (make 4) is a set of support brackets designed to build a box 450mm wide by 425mm deep (edit: make it 450x450 if you've printed the cable management dowel rod holder on the back of the Z tower). Front side is between the X/Y towers. I'm going to hinge the door using a design I found on Thingiverse. The part of the bracket at a 45-degree angle is meant to hold shorter (125-150mm) pieces of OpenBeam to let the bottom frame sit on the table (you can drill the table to use M3 nuts/screws to lock it in place). The single hole at the intersection of all the pieces is for a piece of Openbeam tapped for an M3 screw to be the vertical standard.
[img]http://i.imgur.com/iOXpprL.png[/img]
The smaller part (also make 4) is for the top. Short piece of OpenBeam mounted to the top plate of the printer, with a pocket to capture the vertical standard, tapped M3 at that end as well.
[img]http://i.imgur.com/asWHzfM.png[/img]
I'm printing in Black ABS - the channels are slightly oversized (15.8mm) based on my printer tending to err on the small side on prints. Holes are in theory sized to let an M3 pass through freely (3.5mm diameter), but I ended up needed to enlarge the holes slightly.
The 6M pack of OpenBeam available on Amazon should be enough to enclose the machine with a bit to spare.