I've been wanting to make a down sleeping bag (no quilt for me) for some time now (this forum has been very informative). Lack of funds is one reason I haven't made it yet, but I also have some questions that I would like an answer to before I order material.
I want my sleeping bag to be lightweight, so I'm looking at some of the lighter materials. M50/55 is way too expensive for me. From what I've read M90 is a good downproof fabric for an acceptable weight. I was wondering though if there aren't any other 0.9 oz nylons out there that can do the job and may be cheaper? DIY gearsupply/Backwoods Daydreamer used to have some very cheap 0.9 oz nylon, but they don't sell that anymore.
Does anyone know how owfinc tafetta (http://www.owfinc.com/Fabrics/NylonWoven/taffeta.asp) compares to M90? This is currently the only other source for 0.9 oz downproof fabric besides Thru-Hiker, but there have to be more.
Looking at my neo-air and similar mats with reflective materials also got me thinking. Would it be possible to use reflective nylon? I might be able to get by with less down that way and maybe even save some weight. Does anyone have experience with this? I wonder if breathability might become an issue if I use a reflective outer shell with a normal inner shell. What do you think?
Thanks in advance.
Mark

