How do you keep a sil-nylon poncho clean when you also use the poncho as a tarp?
I use a sil-nylon tarp and after a few nights the tarp is coated with sand that sticks to the sil-nylon when pitching the tarp. The sand is impossible to clean off in the field. I'd like to try having my poncho pull double duty as a tarp but I think the poncho would be very uncomfortable to wear as a garment if it was coated with sand.
Thanks for any tips/info you can provide.

Michael,
I have encountered the very same issue. In addition to the discomfort of wearing a sand-coated silnylon poncho, there is also the weight issue. That sand adds up! Since I do all of my backpacking in the Grand Canyon, sand is a huge issue. My solution has not been the discovery of some ingenious way to clean silnylon. Rather, I bought a Bozeman Spin poncho, which is actually lighter than a silnyon equivalent and made of silicon impregnated fabric that does not have the same sticky quality of silnylon. After one trip in the canyon, the sand accumulation problem was minimal, and it was much easier to brush off sand that did gather. It might be worth looking at, but prepare for sticker shock.

Thanks for the info Dave, the spin poncho sounds like an interesting alternative. The sandy conditions I was concerned with are when hiking in the Grand Canyon so it's nice to hear from someone who has experience in the area I wanted to use the silnylon poncho.
Mike

Aren't there anti-static sprays out there, or is this a figment of my imagination? I wonder if that would help.

John,

My sense is that the sand problem with silnylon is not related to static electricity, but rather to the slight, inherent "stickiness" of the fabric. Everywhere you go in the Canyon you encounter very fine silt particles that are small and light enough to cling to this slight stickiness of the silnylon fabric. I once had to use a silnylon poncho as a ground cloth, very briefly, and two years later I still find silt clinging to it. This problem may be restricted to areas where you're likely to encounter this type of ubiquitous and very fine silt.

David

I think it's a combo of both static electricity and the stickiness of silnylon.

Fresh silnylon can generate quite a bit of static pretty easily. The static in turn attracts dust etc. which reduces static over time. The stickiness factor depends on the type of silnylon. Some brands are just stickier than others, there's actually quite a wide range of stuff out there now with different coating weights.

Because the Spin cloth has lighter sil coatings than silnylon, it tends to be less prone to static and dust/sand pickup.