Last Year I made a Diy Hammock underliner for my Hennesey Hyper Lite. I used shrink storm door plastic , elastic and sewed edge binding all the way around.
My sister gave me a bunch of ripstop so I cut on out today. I havent sewed it yet ,but will be done soon. This idea came from Henneseys four season insulation system. There eggcrate liner pad is available for 29.00 Not bad, underliner is 100.00 and change. I am trying to fine lightweight open cell eggcrate foam? Guess what looks to be cheaper to just bye liner pad from them. I know my big screen tv was packed with it years ago. If anyone has some around let me know. I thought mabe a chepo eggcrate mattress pad may do! Nope to heavy and doesnt compress to pack well enough. I would love to have a down underquilt, but not in the budget right now. I will post a pic or two of my finished underliner when complete! May just have to bye Henneseys Pad, but the DIY in me says keep looking? I must be nuts! If I was smart I would have bought a super shelter system when they were on sale last year for 98.00 No I gotta make one or two? LOL, sometimes we are better off biteing the bullet and drop the cash!