Hello all. I am currently in the process of wiring up my electronics for my CNC router, but as money is tight, I don't really want to buy an enclosure. Is it easy enough to make one myself?

I have access to a water jet cutter at work so was thinking of just having it cut out of sheet metal ready to fold up like a cardboard box. However, as I am not very electronically minded I wanted to ask some basic (probably stupid) questions.

1. How big will my enclosure need to be? I am housing a standard off the shelf 48v PSU, along with the leadshine mx3660. How much free air space do I need to leave around them?

2. What material would be best? Ali or steel, or does it even matter? Can I paint it?

3. What other features should I incorporate? Such as a dedicated earth fixing point?

Thanks.