I had an old cheap metal toolbox that use to piss me off every time I tried to move anywhere. The metal on the bottom that the casters where screwed to was so thin that it would bend any time you moved it, so the wheels never would stay flat or level, one even bent almost to a 90 degree angle when it got caught on a small rock while I had it rolling across the shop one night. Well you can only guess what happen? yep that’s right the tool box flipped! tools spilled everywhere and I took a header over the whole dang thing. Well; I picked myself and my tools up and pushed that box over in the corner with ever intention of taking to the dumpster.
I really couldn’t afford to replace it, and I didn’t have any place handy to put the tools that it was holding, mostly drill bits, marking tools and other misc stuff, that is when I decided to make a new bottom for it. Then while watching some work bench videos on U tube I came up with the idea of making it a rolling work bench. I had some short pieces of 2 x 10s and a small vice; so I cut, glued, and screwed it all together into a nice little handy work surface. The best part I didn’t lose any storage.