You need a secure environment to do that of course. No prying fingers, animals or light fingered passers-by.
I've explained my setup before caveman, but in case you missed it, I'll go over it again.
I buy a very, very cheap case. This case is a full Midi Tower standard. Some Midi Tower cases are not full depth, they are no good and components can interfere with the mainboard etc, you need a full Midi Tower with the long front to back dimension.
Some cheap cases are nasty pressed metal with sharp edges. The ones I buy have rolled edges with plastic caps on the sharp terminations sometimes. They should also have front USB ports and include a bag of fasteners and standoffs. The front panel needs to be nice enough to look at if you intend on leaving it on.
I then strip the case down, removing the side covers, top and front panel, leaving the frame exposed. I paint the bare metal frame (and inside the lid and sidecovers if they are to be refitted) with some metal spray primer and then respray with a bright colour, I usually go for fluorescent pink, orange, yellow, blue or green. The bright color gives better internal lighting than black.
If the front panel is discarded, the buttons wiring etc. can be hotglued into some of the perforations on the front of the frame.
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A plywood base is fine, but it doesn't, on it's own, provide good support for the components. This can be a problem when a heavy monitor cable is attached to the video card and it tries to twist the card out of it's socket. A wooden or other support bracket is indicated where required.
I removed my voice over IP/modem/switch/wireless router from it's case and built a slatted cedar enclosure for it out of a broken venetian blind. This type of router gets very hot and the supplied plastic enclosure seems designed to destroy them at 2 minutes past the warranty expiry date. Mine will last longer now.
The slab of wood the router sits on is a raw and very old chunk of Australian maple that stretches across the room and is my shelf. I found it in an abandoned sawmill.
My computer desk is huge and is made of maple and red cedar from the same mill.


PC cases are built to exacting tolerances and a pre-defined standard. Deviation from the standard will often quickly demonstrate why the standard is in place.
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The ATX standard metal frame is butt ugly, but it's quick and everything fits where it is supposed to.
I built the custom case below out of acryllic and I learned that it is no easy task to make it all work correctly.
