Just got back from trip on beach of Olympic Peninsula - great place for winter trip - too busy in summer.
I'm surprised there was so much feedback - not made of Cuben or anything.
I'll have to try clear 3M tape next time, I think that might work better than duct tape. Or Gorilla Tape - there's so little used the weight probably doesn't matter.
Tyvek would probably work, I've only used it a little as a ground cloth. Is it wide enough for a tarp without having to sew pieces together? The beauty of poly is they make it in huge sheets.
There are three seams on my catenary curve silnylon tarp. The two ridgelines are cat curves. I keep playing with this. Currently I have a short center pole at the bottom - the two ridges with cat curves don't make sense but it doesn't seem to make any difference. What I should have done is make the tarp with two pieces and one seam down the center, same as other similar tarps, like the Cuben one that BPL sells.
Sheet bend at corners - then the edges of the tarp aren't under tension so they flap around a little, but so what I guess.
I have some bubble wrap, not sure yet what I'll make out of it, maybe a vest, 3M tape should be of use.