Alternative Seam Sealer for Silnylon

The caulking-gun silicone will work very well. Just dilute it with mineral spirits – and make it considerably less viscose than SilNet so that it applies more easily. SilNet itself is too thick.

See this article:
http://www.backpackinglight.com/cgi-bin/backpackinglight/make_your_own_gear_sealing_silnylon_seams.html

Jason,
So you are saying that this product that I have will work as long as I dilute it?

Yes, my hiking buddy uses this exact product and it turns out very well. Sorry, I was a bit unclear! Also you might want to read the forum discussion after the article I linked to – good tips there.

Yes that will work just fine. That is what I use (though mine is the GE brand). Don't mix up too much at a time- it will "skin" over quicker then you think and make it messy to work with. It is not as fast as epoxy so don't be afraid, you will be able to tell when it starts to thicken up. When it does, just mix up some more.
I use a paper cup and a popsicle stick, when that batch thickens I just get a new cup and start again.
After it dries completely, lightly rub some sidewalk chalk on the seams to keep them from sticking, or some other non-smelling powder. Talcum powder or the like might be perfumed so in bear country might not be the best option.
Good luck

Actually, you don't even have to thin silicone caulking to apply it to seams. Just put a dab on the tip of a finger and then slide the finger along the seam. It helps to have the seam pulled tight so the sealer can enter the thread holes. It also helps to practice a bit on a piece of paper to get the feel needed for a nice even application. This is the way I seal all of the seams on the smaller items I make; using thinner is too wasteful. I have never had a seam done this way leak. It is, however, a bit more visible than a seam done with thinned silicon caulk.

Another alternative is to use flowable silicone windshield sealant (~$4) and apply it with a foam paint brush. No thinning required.

I finished, but holy crap! Mixing that stuff up was rough. I think I also mixed it a little to thin. I may make a run tomorrow to wally world and get another tube of silicone and give it another go. How do I know if I have sealed it good enough?

How do I know if I have sealed it good enough?

Just inspect the stitching for coverage. As long as you followed the article, you should be fine. I believe this is the method Henry Shires recommends, BTW. Too thin is unlikely to cause a problem as long as the coating is applied everywhere that stitching is present. It doesn't take gobs of sealant, or an especially thick band of it. A thin mix permeates the threads better. Most people overdo it with undiluted sealant, like if you can peel it off in a ribbon with your bare hands! :)

You could apply a second thin coat after the first one dries completely. But if the shelter was under tension and you covered all the stitching, you're probably good. Finding one of those teeny-tiny tubes (.35 oz) for your repair kit is a good idea though, for field touch-ups, repairs, etc. Anyway, enjoy your trip!

Kyle,
Turn a garden hose up high and spray the tent generously for maybe 5 minutes or so, then check for water inside.

> flowable silicone windshield sealant
by Permatex. Good stuff.

US$4 in America. AU$24 retail in Australia. Love those importers and distributors…

Cheers

Kyle, sometimes the thinner the better. When it is thin it can "run/seep" into the thread or seam better then the thicker stuff which sits on top of the fabric, thread or seam. I mix mine pretty thin and have never had a problem and it seem to last just as long or longer.

well I guess it has seeped in real good, because I know I brushed on the solution, but there is no way you could tell. Guess we'll see if that is good or bad. I might turn the water hose loose on it tomorrow.