Earlier this afternoon, I was standing in the basement thinking to my self "I need more flat, horizontal surfaces".
About 6 months ago I bought a 50x50cm ceramic tile at a local home store. It's somewhat flat. (around 0.09mm over the full 50cm length when supported). It's not a surface plate (the little 228mmx304mm granite I have is ±0.00254mm over the 304 length.) but is fine for finding "flat" in most wood projects.
Did some quick design work; I got into using Onshape a few months ago when 123d design decided to shut down.. and have actually really been liking their platform.
I had some 12.5mm inexpensive plywood sitting around, figured that would make a decent simple cabinet. About an hour later and the base box is assembled:
Going to go have a look tomorrow at some caster options; ideally I need to find something between 10-13cm; (though can always rig the casters down a little if I can't find anything around that size)
The top fits pretty well; (~1-1.5mm of play all around). Not 100% sure what I'm going to do with the edges; I designed it to keep the top captive (so I can remove the tile if required) If it ends up being a pain I might end up fitting a ~2-2.5cm melamine sheet on top and just call it a day.
Next stage is to add a pair of slide-drawers. Never enough space to store things! Plus being in the drawer will keep dust off them. I REALLY should figure out a dust-collector for the basement but I keep putting it off expecting that when we get around to building the garage / workshop on the driveway I'll design something in a little better.
Will be glad to have a place to keep all of the measurement / test equipment!