Originally Posted by
Michael W. Clark
Do the legs need to extend down past the casters? If you stop them at the bottom rail, do they add any more strength being another ~3-4" longer not attached to anything?
Remember on torsion box, the plywood/MDF layer adds strength resistance to horizontal racking (keeping it square). For vertical support (bending/flexing in the vertical) it is about the depth of the member (strength in vertical varies with cube of height). Thickness of member helps but is only linear in strength (2X thick is 2X strong).
If you attach an MDF or plywood panel to the top, I think what you have is fine for an outfeed table and could work some as an assembly table or storage area. I would make the legs shorter so they don't drag on the floor if you intend to move it. If you are doing planing, pounding, etc, may need a support in the middle.. The casters from Home Depot that lock the caster and swivel are great. I have them on another cart and use them all the time.