We purchased a heavy-duty tarp from Harbor Freight and we're going to build a frame out of 6" dia. PVC (for the spine) and the heavier-duty sprinkler system pipe tie-wrapped to the stanchions. The advantage to the sprinkler system pipe is it's pre-curved. Saw two other boats doing this yesterday. If you put the spine up high enough, you can get the sprinkler pipe to curve right to the top of the stanchions, thus eliminating them as a trouble spot or having to remove them. Also: If you build the thing high enough, you can work in there in the winter. Or just hang out
I haven't decided what I'm going to use to elevate the spine. It seems everybody else uses wood. I'm wondering if using the same PVC as the spine, or maybe 4" dia., slotted into the spine with T-fittings, and with the bases also formed of 4" PVC with T-fittings, might not work better? The only thing is the potential added expense.