2X tarps
I have used 2 heavy duty grey tarps for the last 5 years ( same tarps) I use a 20X30 for the front- it reaches back to just in front of the traveller and a 20X15 for the rest aft. It hangs just over the rear railing. Overlap about 18 inches in the direction that keeps the strongest winds from getting under. I tried a couple of plastic conduit frames, one in the stanchion sockets and one using larger conduit over the stanchions. neither worked very well, both collapsing, the later bending a stanchion. For the last 3 years I have used a frame built of 1X3 wood- a ridgepole supported by verticals- about 6 as I recall- with supports from the rail to the vertical. Padded the ridge and any other hard spots with sill gasket. Take the stanchions and life lines off.I figure my cost per year even ncluding the duct tape to fix the tarps each year to be about 50$Part of the trick is to use a large enough tarp to get well down the sides. We store with mast down. I tie the grommets to the cradle and get it as tight as possible, I use the allegator type clamps to seal the front together after it has been folded back. That is the trickiest part.