Rather than asking for an idea or a link, I’d like to offer an idea that worked for me. Though I found very pretty and inexpensive project cases for unos with shields stacked on them, I couldn’t locate anything for a mega on amazon or eBay I had previously purchased several “crayon boxes” with latching lids for about 50 cents during back to school season at Walmart. I use them for keeping parts in order, holding all my rechargeable AA and AAA batteries, etc. As I was reorganizing, I looked at one and suddenly realized it was very close in size to an Arduino MEGA. The major modification was using the cutoff wheel on the dremel to cut a slot on the back side for the mega’s “tab” to slide into, as well as opening up the front for USB A and power, plus the power and track connection for the motor shield. But you do not need the lid for the MEGA to stay in place. It’s a press fit. With an Un of course you only need to open one short side for the power connections, but it wouldn’t stay on place if turned upside down, you’d want to do some double sided tape. I thought if I had this issue, others might as well.
So far it’s fine. I just have the one loco, but if heat becomes an issue it would be very easy to put a small computer fan into the lid as a forced exhaust.
I got some fans in the mail, they are the small ones that I use in RPi game emulator cases (nespi) just in case. Right now, no issue,and I doubt I ever will, but I needed one for a nespi so why not buy 4 instead of 1?
