I can't say the misting described can't happen perhaps with some defective silnylon but I haven't seen it and I don't believe it..... I consider the claims to be fear mongering.

Condensation being knocked down by impact on the farbic from hard rain is possible in some weather conditions with the way the shelter is pitched being a factor. Try it some time. When there is a lot of condensation in the morning go out and smack the out side of the shelter and see what happens inside.

I have spent nights in the rain in tents with conventional urathane coated nylon and silnylon. There is no difference. Rain = 100% humidity to begin with. Rain and fog many times go together. In hard rain the air feels very humid even if you are in say a carport where no misting through the roof is going to occur. When it rains hard the drops hit the ground hard and bounce/splash back up. This brakes up the larger drops and creates some mist. Now put your self in a small shelter out in it. How are you going to have dryer more mist free air inside the shelter than is surounding it? Water vapor moves from wetter air to dryer air very quickly. You can see the mist in the air with the beam of a flashlight light both in the carport and in the shelter out in the rain.

Enjoy the experiance of closeness with nature being out in a small shelter in the rain.

Hi All, I agree with Dave at Oware. I've never had a customer say anything about misting either. Heavy condensation can be bounced off the underside of any tarp, and rarely happens. I do have a limited amount of special 40D (not the 1.35 standard 30D) heavy double coated (impregnated) silnylon in med green that is for all practical purposes is completly waterproof. I use it for tougher packs, pack backs, tent floors, super tough stuff sacks (dry bags) and kids gear. It weighs 2oz sq/yd. Fabric weight is about 1.4 and the coating is about .6. My real life test was to stand on a wet cloth and try to push water through the material to a dry receiver underneath. My ball park spec is over 190lbs sq/in as it did not push through when standing sand grinding my heel. It's about twice as strong as the reg 1.35 silnylon. (I have seen some 2nd's 1.35 silnylon that was too thin for tarps. A good general test is weigh. If it is below about 1.25 sq/yd then most likely the coating is too thin. Most 2nds sold by the DYI folks, like thru-hiker.com are solid and you need not woryy about inferior water resistance.) I will sell some of the special weight 40d silnylon for $10p/yd, 3yd min. plus shipping. Contact me. -Ron

Hate to get into this argument, but misting is as real as dirt. That's just the plain truth. I've seen it, and experienced it first hand on very many occasions, and I know the difference between condensation being knocked off and water from the outside spraying in. As to the test of standing on a piece of silnylon in a puddle to test water resistance. I use it for the bottom of my bivy and for groundsheets and find it reasonably water resistant for that. However, if you make a water bag of the stuff and fill it more than 9 or 10 inches deep, it will weep. Not condensation either, bald-faced leakage. That is true of good first quality 1.35, 30D. So fess up. The stuff is good, and the misting is not significant enough to be a real safety problem (probably), but it dern well happens. I do not plan to reply to any responses to this post. You can argue all you want. I know what I know.

deleted - wrong posting

Edited by pue397 on 07/27/2008 09:23:58 MDT.

"I agree with Dave at Oware. I've never had a customer say anything about misting either."

Well, I guess you have now. :-)

I have the Hex Hammock Tarp in Spectralite, which I used over a JRB hammock last month in Vermont. We got caught in the mother of all rainstorms, the kind that, had I been driving, I would have pulled off the road because I couldn't see the road anymore. Fortunately, we had gotten off the trail and set up just prior to the rain starting, and I was lying back in the hammock when the skys really opened up. The tarp was maybe 1.5 to 2 feet over my head, and it was definitely misting through the tarp so that the spray kept landing on my face. Since we had just set up, I doubt it was from condensation under the tarp, and it continued for the three or more hours of the downpour.

Understand that this is an observation, not a complaint. I basically filed it under "yeah, SilNylon tarps do that." I'm not suggesting that torrents of rain poured through, turning the hammock into a bathtub; it was just a bit of misting. More importantly, when I go out again I'm going to take the 6.5 ounce Spectralite tarp rather than a 1 pound plus PU coated tarp, and just deal with whatever misting occurs. I'll live, although I *may* just try to add a bit more of a silicone coating on the underside of the tarp.

8/5/08:

Okay, I'm reevaluating the above statement. I think that if I expect severe rain I *will* take the PU-coated tarp, for a few extra ounces, and enjoy a mist-free evening; if it's going to be drier, then the SpectraLight tarp goes with me for the lighter weight. I guess as I get older I get crankier about comfort, and the inevitable trade-offs between comfort and weight. For me, weight isn't everything, although it's obviously still important. But if I really need something, ...

Edited by backslacker on 08/05/2008 14:22:51 MDT.

Both my silnylon (seconds) MYOG poncho tarps, my first silnylon (1sts) MYOG tarp/Wheelen lean-to and my GG Spinntwinn have misted through. My tarp made of Ray-Way silnylon has NEVER misted through so I firmly believe in Mr. Jardines claim that his proprietary silnylon coating eliminates misting. Also the Ray-Way silnylon has a slightly crinklier feel.

Edited by lollygag on 08/05/2008 13:32:29 MDT.

Not all silnylon is created equal. Simple silicone impregnated fabric will seap under a small head of water (6 to 8 inches) and raindrops will sploot a light spray through it because they focus a very high head on a small area. This is in addition to their knocking condensate off the inside. Double coated silnylon which goes through the process twice - once on each side - is functionally waterproof and will not mist. Ditto for fabric that has a film of polyurethane over the silnylon. However, the latter has all the disadvantages of polyurethane and tends to delaminate.

I intend to try to add more silicon on the underside of the tarp to gain a better seal against water penetration. It will add a few ounces, but still be much lighter than straight PU-coated tarps.

Edited by backslacker on 08/06/2008 04:06:55 MDT.

And some silnylon is a blend with a touch of urethane in the
mixture which can be applied to one of both sides and in lighter or heavier amounts.

There is no free lunch, although some are tastier than others.

I'm assuming that the MLD SpectraLight [Cuben] is silicon coated only - no PU.

While there may no free lunch, sometimes you can season to taste. :-)

Edited by backslacker on 08/06/2008 04:06:19 MDT.

Would GTX PacLite laminate be heavier than medium weight PU coating?

If so the expense may be worth it to avoid the misting problems in Silnylon fabrics.
But then it's likely not going to pass flame retardent tests.

Jim Woods 5:1 ratio of mineral spirits to silicon applied with a VERY low nap roller may just be the answer for those who love their tent but hate its misting.

Eric

Edited by Danepacker on 08/05/2008 21:20:17 MDT.

How can you tell if the silnylon is single or double coated ? Is the standard 1.1 (1.35 after coating) fabric sold by thru-hiker, or OWFINC double coated ?

Also, does anyone know where to get 20-40 denier ripstop with silicone coating on the outside, but a PU coating on the inside ?

No idea whether it's single or double coated, only that it's .65 SpectraLight (Cuben), and I assume that there's no PU coating on it.

JohnG.
The only way to tell about double coating is what the manufacturer claims. American Home and Habitat (americanhomeandhabitat.com) is one source. It sometimes (sporadically) shows up at other fabric sources.

None of this applies to Cuben which is a fiber-reinforced Mylar (polyester) film.

I say again, there is no free lunch. A lightweight coating,
say .3 oz, whether silicone or urethane is going to have similar
water resistance under pressure. If you increase the coating
to .5 oz or 1 oz or 1.5 oz or 2 oz you will get correspondingly more resistance under pressure as well as
more weight.

Paclite in its lightest versions is similar to a 1.9 oz
nylon with a .5 oz coatings or urethane or silicone.

The advantage to silicone is its durability in long term
damp conditions and that fact it increases the tear
strength of the fabric it is applied to.

Again I say that you could carry two silicone tarps for
the weight of 1 urethane tarp. Double them up and you
would have no misting issues at all. Or maybe carry
a bivy sack instead and get a ground sheet and bug and
wind protection too.

"I say again, there is no free lunch."

Unfortunately, too true.


"Again I say that you could carry two silicone tarps for
the weight of 1 urethane tarp. Double them up and you
would have no misting issues at all. Or maybe carry
a bivy sack instead and get a ground sheet and bug and
wind protection too."

I would assume that adding extra silicone to one tarp is lighter, but functionally equivalent, to two normal silicone tarps.

I think what I've come to is, I'd rather carry a few extra ounces and not have misting spray over my face at night. As long as the ounces don't start adding up to pounds...

Damn, I *hate* trade-offs. :-)

This discussion has been interesting to me. I just got back from 2 weeks at Philmont Scout Ranch, New Mexico. 2 of us had Gossamer Gear "The One" tents with spinnaker cloth. It rained six days or nights. I had light condensation inside the tent on the wet days. Very little to none on the dry days. One night I distinctly remember feeling a misting in the tent. It had rained that day and the tent was wet. A light layer of condensation had formed on the inside of the tent. That was a first for me in that tent. The misting was also noticed by the other guy with The One. It was only noticed one night even though we had other nights with substantial rain with large puddles around the camp.

The misting was not enough to wet or saturate a bag. In fact. it was almost so little I thought I was imagining it. Is it real or is it Memorex? I don't know.

"It was only noticed one night even though we had other nights with substantial rain with large puddles around the camp."

That was in a low humidity environment. It gets more interesting out East where the humidity often hovers in the 90s.

The misting sounds more like fabric penetration than condensation being consistently knocked off (not that they're mutually exclusive).