out of pure curiosity i decided to make an underquilt out of a space blanket. i pulled the blanket into a hammock shape by just tying the two sides together with a nylon rope, then i used a presik knot to keep it tight against the hammock. i depart for my hanging slumber in a few hours and will continue to check on this thread if anyone has ideas.
current temp is 30, and it isn't supposed to get much lower. no precip, and i'm using a tarp as a "A" frame shelter.