[Al Skierkiewicz]

I would envision this could be made legal using specific materials. The other factors I also considered is the space in which you have to work and the power of the motors available. 29 x 36 is a small footprint in which to add four of these devices. You also will not be able to climb very well without having the center line of the screw be fairly high. I am guessing with all the limitations, a screw could not be made to climb the bump due to the size and power needed.