Tarp Building Pointers

[MacGyver2005]

My local Wal-Mart has DWR nylon in the $1 bin so I am considering snatching it up and making a tarp. I am thinking I can waterproof this with the "homemade" method of silicone and alcohol. How do I make this concoction? I have an air compressor and paint gun, would I be able to use this to apply the waterproofing? What is a good lightweight method for tie-outs? Also, what does DWR stand for? Are there any suggestions for me to keep me from making typical mistakes? Thanks in advance!

Regards,
-MacGyver
GA-->ME

[Seeker]

you lucky dog! i've only been able to find 1.1 oz silnylon there twice, and even then someone beat me to most of the roll (or whatever it's called) so i only got about 8 yards.

i've lost the link, but iirc, it's a 3:1 mixture by weight of mineral spirits to silicone caulking... i used roughly a tube of clear silicone caulking to about 3/4 of a 3lb coffee can full of mineral spirits. takes a LONG time to dissolve, but that's just the way it is. be patient and stir... i painted it on with a 3" wide foam brush, having hung the tarp on my clothesline outside... only used about 1/3 of what i'd prepared, for an 8 x 10, coating both sides...

if you mix it a little thinner, you could probably get it through a paint gun, but it's not worth the waste, in my opinion... you an also buy spray cans of silicone (camp dry) in walmart's sports dep't. they work too, but more for re-touching.

i used synthetic webbing about 1'' wide for my tieout loops, but if i were to do it over, i'd probably find some 550 parachute cord, slip the middle strings out of it, sear the ends of a 6" piece, and sew that into the hem, leaving a 1-2'' loop.

for tie out cords, kelty triptease is pretty light (50' weighs 1oz), but i have discovered that i don't like how well it shows up at night, and have gone back to a thin nylon cord... might weigh a bit more, but i really like being invisible at night since i usually hike alone.

[Just Jeff]

DWR = Durable Water Repellent

What color is the material?

[Footslogger]

[quote=MacGyver2005] I am thinking I can waterproof this with the "homemade" method of silicone and alcohol.
==============================================
Silicon/Alcohol ?? I generally use silicon and mineral spirits.

Maybe I'm thinking about seam sealant.

'Slogger

[erichlf]

I use 1/2" Grosgrain ribon for tie outs. This is also what Ray Jardine suggests, amongst many others.
And for tie outs I use EZC line it is bright orange
Weight:
0.018 oz. per foot
Strength: 275 pounds
Quantity: 50-foot lengths
Price: $9.95
http://www.gossamergear.com/cgi-bin/gossamergear/ezc_line.html

[erichlf]

Also, if you are willing to part with some of that DWR I would be willing to buy 5 yds at $2/yd +shipping

[MacGyver2005]

Wow, thanks guys.

Seeker: Thanks for the tips on the waterproofing. The parachute cord tieouts are a great idea!

Just Jeff: Thanks for the info, I finally found the answer on the net, too. Unfortunately (IMO) the nylon is bright orange.

Footslogger: You are correct, I think I am so acustom to alcohol with stoves that it immediately came out instead of mineral spirits.

erichlf: I can probably do that for you. Like I said, it is bright orange, and I do not know the weight of it either. Keep in mind that I believe it to be DWR; it has the "checker-board" pattern to it and is difficult to blow through. I will gladly grab some for you if you are truly interested.

Thanks guys, this is very helpful information. I think I might throw together a hammock, too!

Regards,
-MacGyver
GA-->ME

[MacGyver2005]

Ran into Wal-Mart, they didn't have much left. What they did have I promised to erichlf, so I guess I'm just going to be keeping my eyes open around town in hopes of it popping up again.

Regards,
-MacGyver
GA-->ME

[Rambler]

The purpose of mixing the sealant with "spirits" is to thin it out so you use less and it spreads easier. As it dries, the alcohol evaporates leaving only the sealant. Personally, I have found this more trouble than it's worth. Needle dispensers are not worth the bother either. I just spread the sealant on right out of the tube! Do not use silnet on other nylons, just silnylon. It will just flake off other nylon as it dries. DWR is a coating that can be sprayed on after extended use.

http://www.rei.com/online/store/LearnShareDetailArticlesList?categoryId=Camping&url=rei/learn/camp/outwaterf.jsp