Build sturdy stands using strut
In looking for an affordable way to make rock-solid, good-looking, and eminently functional machinery bases, it occurred to me that steel strut channel, used in the building trades for supporting electrical, plumbing, and mechanical systems, might be worth trying. So I bought a few 10' lengths at a home center and soon found that strut makes great legs when joined top and bottom with 2×4 rails. (Pine 2×4s provide plenty of strength for typical machines weighing 100–300 pounds, but for heavier loads, use hardwood.)
To get a sturdy base, prepare the 2×4s for a tight fit to the strut. First, plane the wood to match the inside dimension of the strut, and cut tight-fitting dadoes near the rail ends for holding the curled-in strut edges. Tapping the snug rails into the strut squares up the rigid leg assemblies. Then, drill a 3⁄8 " hole completely through each strut-and-rail joint to accommodate a 5⁄16 " bolt secured with a nut. Simply screw on the remaining 2×4 pieces and casters to complete the base. The slots in the strut channel come in handy for mounting motors, tool accessories, and organizers.
—Wes Swartout, Spearfish, S.D.