Rather than do that, I'd MUCH RATHER order any tarps from Brian at OES
http://www.outdoorequipmentsupplier.comHe makes each tarp custom to order, and will add tieouts wherever you want, and make whatever size tarp you want, out of whatever materials you want. Hard to beat that.
He's been making tarps out of spinntex fabric, which is obnoxiously lightweight and crazy waterproof. WAY WAY more waterproof than treated cordura nylon, which can mist-through, and even more waterproof than silicone impregnated nylon.
I have an 11x10 silnylon tarp from OES that packs smaller and weighs less than most 8x10 tarps you'd find at a decent outdoors store.
