Cherry Pi III USB and Ethernet box

My original "Cherry Pi III USB and XBox power box" worked well - but I found that the XBox 203W PSU just wasn't powerful enough to drive my printer. As soon as I turned on both the hot-end and the heated bed, the green light on the PSU briefly turned red and the controller board reset itself.

After changing the controller board from RAMPS to Duet I realised that I needed an ethernet port as well as one for USB, and I wanted to remove the hole for the XBox socket - but making changes in FreeCAD proved to be horrendous, so I redesigned the whole thing in OpenSCAD.

The SCAD files are (mostly) parametrized so people can adjust things to suit their own needs and, if they know OpenSCAD, they can add, remove or adjust the lid holes to suit their needs, and adjust the size of the box to suit.

The image above shows the Duet board in my Cherry Pi, and you can see the extension cables snaking around to the right-hand side of the board. Note: the photo shows the old case - the principle is the same.

Although designed to fit a Cherry Pi, it should also work for any similar printer that uses 2 rails made from 20x20 aluminium extrusion and M5 t-nuts.

The OpenSCAD lid file should be adjusted to suit your own extension cables, specifically the size of the socket hole, plus the spacing, size and alignment of the screw holes. The parameters for each connector are associated with its relevant SCAD code.

You will need to put the connections_box_variables.scad file alongside the files for the case and lid - this contains the global variables for both parts (and ensures that each will match the other).

The mounting holes are for M5 screws, and the lid fixing screws are #4 x 19mm (or 25mm). My USB and ethernet sockets each used M3 screws to mount to the lid.

For printing, use whatever filament you prefer, PLA or ABS, although a brim is recommended for the ABS to avoid warping. I used an infill density of 50% so that the rear plate is reasonably strong. If your printer prints a bit "fat" then you may need to scrape the edges slightly to make the lid sit nicely, as it was designed to be a snug fit. Apart from that everything is straightforward.