Bought some Cuben from Cubic Tech, and have been exploring different ways to incorporate it into a tent; but something has been bugging me, and could not put my finger on it.
So, decided to print out and re-read Lawson Kline's winter 2009/2010 thread, "Cuben Tent Question." It reminded me of Prince Myshkin's conversations in a Dostoyevsky novel I'm reading, but I'll spare you all about that. And the automatic updates on the Avatars that made some of the posts incomprehensible made be wonder about revisionist history in a totalitarian cybertech paperless world; but I'll spare you all about that too.
One item that caught my eye was Franco Darioli's New Year's Eve post, and his obervation that,
"Cuben is a manufacturing process not a particular fabric or laminate. So many variations are possible, however they all have some "creep", that is, with pressure they go out of shape. Like say Gladwrap, once expanded it does not go back to the original size."
So I looked at a sample of the CT Cuben I've been using for various tests, and pulled and stretched it, diagonally to the fabric threads. It became quite mishapen, and unlike, say, silnylon, did not resume its original shape. So I pulled and stretched the mishapen area on the other diagonal, and this made a large pockmark in the fabric that would not resume its original shape.
A major concern is that when subjected to high winds, a Cuben tent wall may permanently distort into a concave shape, and thus become incapable of remaining taut and resistant to flapping, billowing, snapping, internal sagging and dripping, and all the other plagues associated with poorly designed and/or constructed tents. A slightly lesser concern is whether a hailstorm could make a Cuben tent wall look like a cobblestone street.
So then I tried the diagonal stretching on a lighter (.5 oz) 1K Cuben sample, from Zpacks, and found the stretching and pockmarking was much less.
So then I looked at a torn label on the material from Cubic Tech sold as "CT2K.08" and found that it read, "CT2E.08."
The Cubic tech info states that the "K" signifies a polyester film, but nothing about "E". I have emailed them about this and am awaiting a response.
So many of you have posted about experience with shaped Cuben tarps, and lately even tents to some degree, that I am hoping you might share any experiences, good or bad, along these lines. If you are reluctant to post publicly, I am at firstname.lastname@example.org, and will keep any eMail responses strictly confidential.
I would very much appreciate any guidance anyone might provide on this issue, as I have invested some considerable $; but mostly, really do not want to make a much more valuable investment of time and effort if it is going to be wasted. Being MYOG folk, I trust you know what I mean.