how to hang curtains accross large span
I'm thinking of hanging some outdoor curtains from my covered patio to block the western sun in the afternoon. I prefer to not build a wall or lattice, and I don't want the hassle of outdoor roller blinds. I found some panels made for outdoors that will work, but I am unsure of how to hang them. The span is about 20 feet, and I need them be pushed all to one side when not in use, so I cant' just mount multiple curtain rods. The curtains have grommets, so I need something rather thin that will fit through the grommet holes. (I hope this makes sense.)
Does anyone have any ideas? Maybe somehow joining 2 10-foot lengths of conduit piping? Or, hanging them from a thick cable? The problem is not being able to use mounting hardware to support the middle of a rod (curtains need to be able to slide accross the entire span).