First up No its not a new fangle-dangled revolutionary string jacks? Its a simple platform I made to maneuver projects on in and out of the garage.
As there is an abundance of Telstra rope always lying about I used it as a means of steering the trolley It might look a little chatty but the cardboard is there for stability and prevent damage to projects its supporting. The construction is 50 mm x 100mm beams of construction lumber screwed together and a 19 mm plywood platform on top.
Underneath is some serious wheels similar to a small version of a shopping trolley wheel, they each have bearings and are rated to 50 Kgs per wheel. They are mounted on blocks and attached to the top platform and to the sides in a lowered aspect similar to a 48 Dodge COB. the wheel assemblies are attached to the trolley by hardwood (lowering) blocks and 12mm bolts and nuts, so its more than load capable without the concern of a narrow spindle wheel from an office chair or the likes bending or collapsing under load.
That's my 2 cents worth
Oh and some trivia
BTW did you know Sam Maloof did a stint in the US Army?