I spotted this October 2000 issue of American Woodworker. Since my shop can only be as big as one half of a two car garage, I'm always looking for
ways to get the most bang for the space.
This project served several purposes and does them all well. I wasn't able to actually build it until I moved back from Europe in June, 2002 but I think it was worth the wait. It gives me a workbench, plus storage for 3 tools and rolls into the corner when I'm not using it.
The cabinet is made of MDF, which is basically sawdust and glue, squeezed together under high pressure and temperature. It's extremely dusty when cut, so made sure you have good dust collection and probably a
dust mask too. It's flawless and gloss smooth (unlike plywood) but has no structural strength.
It's also damn heavy and with 3 full sheets of it in this project, a scheme to support its own weigth and the weight of the tools had to be invented.
The tosion box below is that solution.
A torsion box is a framework of half-lap joints and a LOT of glue. In this configuration, and with the pieces standing on edge like I-beams, it has tremendous rigidity and load capacity. This part sits right on top of the casters and the rest of the box is built on it.