I undertook the task of making a roof rack. Again. Learning from past efforts, this is what I came up with. 1" square tubing with conduit, rounded corners. It is rigid, light, makes no wind noise and it cost very little to make. The powder coating was about he same cost as the materials. I'm in it about $85. I cut the cross rails down to essentially be just plates into which I could thread the attachment screws for the rack.