Here's how I made mine, I used 3/4" pvc, the 1/2" just seemed too flimsy to me too. I also didn't want the extra pieces at the bottom... while it might make it a bit sturdier, that bottom frame would limit having to put trays inside that space. I've since added another 2' piece with a connector to the top bar to stretch it to 4' in length. I never glued the pvc pieces, which made it simple to swap it from 2' to 4' and back again if I ever want it smaller. It sags very slightly from the 2 grow lights attached, but they're very lightweight, so it's not a problem, and it's sturdy enough as is. I made it 2' high so I'd be able to use it for taller plants (and in 2 months, the seed vines really start reaching up there, so I'm glad I made it higher than recommended), and I raise the lights just by how much the chains are wrapped around the top center piece. With 2 separate lights, it lets me have 1 light for lower growing plants and 1 raised higher for the taller ones. The pvc was only around $11.
