So my garage was getting a little out of hand, so I decided to get my surprisingly vast collection of sheet goods off the floor and wall between which they had erstwhile been propped. I whacked together a 2 foot by 8 foot floor out of 3/4 inch OSB and a frame of 2x4s. I left the short beams long enough to protrude on one side, but, due to a miscalculation on my part, I left them a little too long. I fastened six 4 inch swivel casters (two with brakes) to the frame. The upright supports are also 2x4s. I cut the slanted member 48 inches long and put an 80 degree mitre on the lower end. The vertical member was about 51 1/2 inches, which was as tall as the slanted member plus the height of the OSB and the 2x4 to which I attached it with lag screws. I put a 10 degree chamfer on one corner of each of the vertical members, and attached them to the slanted members with countersunk wood screws. I attached the slanted members to the OSB with some pocket screws.
While the cart is okay, I definitely have room for improvement. Got to start by cross bracing the uprights so I can use them to push and pull the fully laden beast. I also either need to trim those horizontal pieces of the lower frame or use them for something else.