We needed some way to bungee the tripod to the dolly. There just happend to be some 12" long 1/4" bolts in one of the tech shop bins. I used tech shops two pin roller to bend the bolts into hoops. This was a bit tricky because the roller is not designed for 180 degree bends. So i fudged a bit and bent by hand.
advise: if you want two nice hoops, make three or four and take the best of the lot!
second picture shows hoops welded to frame. i cut the remainder of the hoop off with a sawz-all.
third picture shows the painted frame with hoops and the pads to hold the deck screws.