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RetroBrew has a respectable variety of boards designed for the ECB bus, a late-80's eurocard form factor using a 96 pin DIN connector. In the original form, it only used the outer 64 pins, leaving the middle row on the connector unpopulated. Retrobrew has extended the classic ECB with an upward compatible extension using all 96 pins, which allows building 16 bit board with a wider address space and other extensions.
I've found a couple of ECB card cages out there in surplus market, a 6 slot and a really huge 18 slot. I've found both of these overkill, and I also wanted to build a quite small machine using the Retrobrew 3 slot motherboard. This article describes the card cage and presents the source code.
I designed and wrote the cardcage using openscad, a text based language used to describe 3d shapes. it has a C ish syntax and is concise and expressive. source code is attached and is also available on guthub: https://github.com/cm68/ecb_cage_3
The cage has 3 slots, with 2mm grooves supporting the boards. the grooves run the length of the 160mm card. the slots are 100mm wide.
The 4 parts assemble with printed dovetails. they might need a little sanding or filing to fully engage. I got mine to fit tightly with a little help from a vice grip. I used no glue, and don't think I need it. Your mileage may vary.
The motherboard is supported on 3 sides and slides in to the assembled cube. If you mount it open side down, you'll need to contrive some way of holding it in, or it will fall out if no cards are installed.
I'm going to mount the molex power connector inverted on the solder side of the motherboard, and put the power switch, LED and reset over there as well. This is where individual requirements will dictate what goes where. Hardwiring directly to a 5v supply, having no power switch, etc, are all options.
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