As a member of the Yahoo ultralight backpacking forum, I get interesting emails from men and women who are constantly searching for solutions to their quest to be as light as possible on the trail.
Paul Sailer offered this tidbit for making a 1 oz chair frame for your Thermarest sleeping pad.
I assume he is talking about the Thermarest ProLite 4, size small (20 x 47 @ 17 ounces). But I’m guessing a Therm-a-Rest ProLite 4 Fast & Light Mattress (Regular) regular (20 x 72 @ 1.5 pounds) will fit as well. Sailer writes:
The Thermarest seat is a little small to support your back (only 11 inch by 15 inches).
However you can make a 1 oz chair, simply as follows if you have a sleeping pad.
1) one long piece of wide webbing (as wide and lightweight as possible) and
2) two plastic snaps like those used in shoulder or sternum straps on packs — that fit onto the webbing so you can join two pieces of webbing together and adjust the length.
How to make the 1 oz chair
1) Simply sew a loop on one end of the webbing large enough to go around your left knee when you are sitting on the ground with your knees bent,
2) put the long piece of webbing around your back and loop around your right knee, and attach and sew the two pieces of the snaps in such a way that you form an adjustable loop that can go around the right knee and tighten it.
The result will be a camping chair that is quite comfortable, and adds only an extra ounce to your pack weight,–and even less if you use the webbing to strap down your gear or for some other purpose
a) simply sit on the sleeping pad with your knees bent with the pad under you and behind your back, bend your knees
b) and put one loop around your left knee, the webbing around the back of the sleeping pad, and
c) put the other loop (with the adjustable snaps) around your right knee, and tighten until you get enough comfort and back support
Alternative Method–using premade webbing loops
Alternatively if you don’t want to sew, instead of one long piece of webbing, you can obtain the same result using three separate loops of webbing: two small loops of webbing (large enough to loop around your knees when sitting, (one of which is adjustable in size) , and one large loop
Simply interlock the three loops with the large loop around your back and the two smaller loops to go around your knees when sitting, and adjust the length of one of the knee loops for comfort and support.