Vertically challenged New Guy

[professor]

Mine weighs about 600lb empty. I used .250 2" square tube for the frame and 18 guage for the box and top. The top is so heavy I have gas springs to lift the thing. The box and fenders are framed with 1" 16 guage square tube and the inside is lined with cedar. I made the hinges out of 1/2" pipe and 1/2" cold role steel threaded top and bottom. The box size is about 3' by 5'.

I am no engineer but all this is probably to heavy for the Harbor Freight frame. You might consider a treated wooden box.