I've been using this setup since about 2014 without issue and haven't seen it online anywhere so here it is: All you need is four 1/2" iron pipe tee fittings and five pieces of 5/8" rebar (#5). I had 20' pieces of rebar cut into 4' lengths at a concrete supply place. The only work you might have to do is deburr the ends of the rebar if they won't fit through the fittings. There is a bit of a learning curve setting them up but once you have it down, it's easy. I start with the cross bar already having the fittings and target on it. Stick the first two legs in and splay them apart a bit. At this point you should be able to put tension on the legs and fittings by pulling the cross bar away towards the other legs. Stick the other legs into the other two fittings and pull the legs away from the other side so there is tension in the stand (usually I have a bit of flex in the cross bar). To level the stand all you do is keep tension on the stand while widening or narrowing the legs. The obvious weak point is the pipe fittings getting shot but I have yet to hit one and they're cheap. I think back when I put these together it was less than $20 per stand. 
Here it is with my 60lb 24"x24"x3/8" plate along with my PVC rebar carrier I made. This was an absolute bitch to set up without help
Here it is with my 60lb 24"x24"x3/8" plate along with my PVC rebar carrier I made. This was an absolute bitch to set up without help
