Most clever idea I've seen for spreader bars is to use an arrow shafts. Hunting arrow shafts use inserts that allow various "points" to be threaded into them. Turns out this thread is a standard 8-32. You cut the arrow shaft to the right length, epoxy inserts into BOTH ends, then use 8-32 screws to attach them. Bow hunters know what I'm talking about. Next time your in a sporting goods store that sells bow hunting equipment check it out. It's light, stiff, strong, easily adjustable, and removable.