Just scored several yards of ripstop from wally's $1 bin in Cullman, Al ... Measured the dimensions and the weight, did the math, ~ 1.09 oz/yd. Planned to use it for a tarp... but... it fails the water test.

So... Can you DIY to make ripstop into sil? If not, can you add reliable waterproofing for less $ than it would cost to just buy sil from Ed? I don't want to waste time making a leaky tarp! But I also don't like the thought that I just blew 10 bucks on fabric that I probably won't use up anytime soon. I can make a few things, but 30'?