The "Boom" is a 8' section of 2+3/8" galvanized steel fence post (with end-caps that have been drilled and grommetted for the power cable to the hoist).

The wheels are rubber, and rated for 350 lbs (presumably for an exclusively downward load). I built the hexagons intentionally too-tight to cause a slight compression of the rubber while the boom is inserted. It glides easily, and even admits (slow) rotation during translation.

The hoist is some Chinesium special that isn't rated for more than 220 lbs. I will trust it to approximately 75% of that rating.

The bearing is 1/3 the length of the boom at maximum extension.