Update on 2017 June 13
v3 looks great. Full access to both usb ports and the hdmi ports.
Since my plan now is to have the control node be a pi zero w and accessing the device wirelessly, then the fan unit could just be an 80mm fan. A much smaller box than I originally planned could be under it that bolts to the fan and then have feet be screwed on by the same screws that hold the fan on.
Update on 2017 June 12
Just finished the 3rd version of the build with just a few minor tweeks. Printing it right now, will pull v3 if there is anything major comes up during printing.
Going to design the base next and get a raspi 2 installed into it by the end of the week. Work out some proof of concept things. Planning on hitting micro center next week, and picking up some micro sd cards so I can program all of them, I may put a raspi zero w into it instead of a raspi 3 just to keep it pi zero only
Update on 2017 June 11.
Finally got 12 raspberry pi zeros. It took a long long time. L
I printed the case and it was close, but just didn't fit correctly. So I made adjustments and am in the middle of printing again. I have uploaded my current work which is v2... if I make more changes it will be v3.
Getting closer and closer, will have the final project tomorrow night.
There is a base file that this cluster is designed to fit onto, with a 120 mm fan in the bottom. A raspberry pi 3 is supposed to be screwed into this base and then a fan added. Need to make a few more holes for power and a power switch.
This is a work in progress. Just posting it now to get some feed back. My write up of the project is at blogger.
This case is designed to allow you to put up to 12 PI Zeros into a single small computer case, wire them up with one pair of wires between each PI and run serial networking between them all. The benefit of this is very low latency communications but at the cost of low bandwidth. This is actually a very acceptable trade off with tasks that have frequent small messages that must be processed as quickly as possible. A single master node would be connected to a network switch and this would be used to dispatch jobs to the cluster. The short wire paths between boards should improve latency. I got this idea after reading about how the early Cray computers were constructed in a C shape to reduce wire length.
Eventually this will be a stack-able design and allow you to cluster many more machines in a small area. If this works for pi zero computers, then it would work even better using a Raspi 2 and a Raspi 3 when it comes out will have even more performance, or even some other computer board that is even higher performance and low power consumption. It should be straight forward to modify the function that is called to cut out the proper holes and slots for any of a dozen or so boards and adjust the quantity that you want in the case.