lightest available urethane-coated fabric

Bender uses some 30D stuff doesn't he? Maybe see if he can make it available by the yard?

The white, 30D heat-sealable nylon that Bender uses (which is essentially the same as the stuff available from Seattle Fabrics) would work but it weighs about 3oz/yard (with some batch variation). I don't expect to find urethane-coated nylon in the silnylon weight range, but I hope to find something lighter than the heat-sealable stuff…

Oh interesting. Except for cuben I'm a fabric idiot.

would cuben work as the waterproof fabric? not sure your application or budget but cuben can be bonded to cuben and i am sure it would be the lightest/strongest option but don't know your application.

Also the 70D stuff should only weigh 2.2oz/yd2

-Tim

Thanks for the tip, Tim. 2.2oz is acceptable, I think. Where did you see that material?

I'm only considering coated nylon instead of cuben because I'd like to put abrasion-resistant patches on a down-filled cuben parka (a project in its second year that may never actually yield a finished garment).

The heavier weights of cuben have much thicker mylar layers as I'm sure you know. The new 1.2oz cuben uses the same thicker mylar membrane as 1.5oz but with less spectra. 1.5oz cuben is really tough so this should be too. Since abrasion resistance is what you're going for, this seems like a good choice. I feel comfortable using 1.5oz cuben as a shelter floor without any additional groundsheet. You can buy 1.2oz and 1.5oz cuben at Zpacks.com for $28/yd.

Dan, I think you are probably right in suggesting that cuben will be competitive in abrasion resistance with coated nylon at any given weight (and superior in tensile strength). 1.5oz cuben would probably serve me as well or better than coated nylon of equivalent weight. Thanks for the suggestion. I'll post my observations as this project (gradually) progresses.

1.9oz 70D nylon ends up running about 2.2oz after the coating. Quest, OWFINC.com and all the others have a material like this and i have made a lot of packs from it with never a tear, scuff or other problem aside from pine sap sticking to it, but that will happen to anything.

Again, i agree that 1.2oz cuben is the lightest/toughest option, just have to choose cost vs weight. Weight wins!

-Tim