what's that?

I made the top (hinged) attachment bracket for the hoist mast and have (temporarily) bolted it to the top deck of the cart.

A semi-circular cutout in the channel will be made and the mast welded to that.

The channel will be welded to the hinges.

The hinges will be welded to the backet.

The thigh bone is connected to the leg bone.

There will be a similar bracket for the bottom deck. It will receive the bottom of the mast, which will be held in place with a removable pin.

All this so that the mast can be lowered across the top deck; otherwise I couldn't get it into and out of my shop.

aside: there are two pieces of "U" channel in this photo, both were fabricated because deep U-channel isn't exactly common.  Both are ≈.115 in. wall thickness claiming to be one-eighth inch.  The top (movable) bracket, that is sitting on the hinges, one is 1x2 and was made by milling out one of the short walls.  The bottom one in the image (bolted to the cart edge) is 1x3 and was made by welding three pieces together. Turns out my employee discount (on steel at least) is really, really good, because the store cost is really low, such that I can skip driving out to the scrap yard for many simple things pieces. I will probably be leaving that gig soon and by the gods I sure will miss that employee discount!

 sigh: I bet there aren't many steel yards where we plan to move up in the mountains.  sigh.