I have to put a PC in an awkward location (it has decent ventilation, but is L-shaped). I cannot find a case that works in the location I need to use so I am experimenting with mounting the computer on a piece of wood. Do I need the motherboard tray for grounding or other electrical benefits? Normally with everything in a case there is a metal cage around the components. I assume that if the case becomes charged that is a very bad thing for the user. However is there any electrical need to have the components mounted in a case?
I was planning to use a motherboard tray I salvaged from an old case, but the tray is too long. I need to either cut it shorter (which will likely leave a nasty edge) or ditch it altogether and just put the motherboard pegs into the wood. If I need the tray I will make sure all components or their mounting brackets have some contact with it. If I don't need it then I will put it out for recycling with the rest of that old case.
Take a look at breadboarding. It's typically done for testing, but could be set up more permanently.
I don't believe there is any actual need to build a computer in a case, besides the obvious protective and ventilation uses. That said, I'm not an expert on the more technical aspects of computers, so this may not be true.
^Agree. It should run fine on a board. Just make sure you don't let any cats near it! No carpet either. As long as it is protected from any large sources of static electricity (like cats) and well ventilated (depends on the parts, but you may want to put a desk fan over it) it will be fine.