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Nathan Watts
(7sport) - MLife
Re: MLD superlight on 03/04/2013 18:32:00 MST Print View

Hey Ian.

I have a Soul with cuben floor. The floor has held up well for me. Prior to this I had the silnylon floor version, but never put it to use before jumping on the upgrade. The nice thing about the silnylon was that it packs up smaller than the cuben. They both weighed about the same (sub 12oz) but the silnylon floored one lacked the size zipper.

The cuben feels more robust in hand than the silnylon did, but maybe the cuben on the soul is heavier duty than that on the superlight.

I try to bring a 1/8" CCF ground sheet to protect it when I can - but that's not always the case if I'm trying to keep pack volume to a minimum.

Ian B.
(IDBLOOM) - MLife

Locale: PNW
Re: Re: Re: re: bivy questions on 03/04/2013 18:38:12 MST Print View

"Waterproof/breathable bivy sacks were ultralight "bombproof" solutions back in the 1990s, when solo tents were 4 lbs."

An therein lies the problem. It's hard for me to justify buying a stand alone bivy system like the OR Advanced Bivy Sack or USGI bivy at 2.5 lbs when I can achieve the same result (with better comfort) with a Mid and ground cloth for half the weight.

The MLD superlight appeals to me as at 5.5oz it replaces a bug net and ground cloth and in some cases saving me weight but once I start shopping the REI, OR, BD, etc bivys which are pushing >16, 24, and even 40ozs the perceived benefit quickly disappears in my mind.

Only exception I can think of are camping in situations where a minimal footprint and quick deployment/recovery are in order.

Richard Fischel
(RICKO) - F
if you want to sleep out in a field on 03/04/2013 18:40:47 MST Print View

keep an eye out for an integral desings unishelter in event. they made them for a couple of years and they show up on ebay and some of teh other outdoor boards evey once in a while. you might also try some of the retailers who may still have one in stock. integral desings makes a couple of diffrent event bivies currently, none of wich are full event. as far a weight goes, my id full event overbag is about as simple as it gets, and it's just over a pound. it will be tough to break the 1 pound barrier with a full event bivy that has any sorts of features.

Ian B.
(IDBLOOM) - MLife

Locale: PNW
Thx Nathan on 03/04/2013 18:43:22 MST Print View

That's good to know; I don't own any cuben products yet and I'm in the market for a few of these items. I'm sometimes torn between buy once cry once and othertimes just cutting a corner here or there so I can drop a couple Lbs quicker. I'm sure diligent site selection helps with either fabric as well and who knows what that bivy was subjected to.

I'll try to find the thread later but I've done so much web surfing for bivy reviews and there is so many threads to wade through it may become mission impossible.

Edited by IDBLOOM on 03/05/2013 07:12:23 MST.

Max Dilthey
(mdilthey) - M

Locale: MaxTheCyclist.com
Rab eVent on 03/04/2013 18:45:08 MST Print View

If I can't get in touch with Ron about getting a Soul, I'll think about the superlight. I liked the Rab one on Gearswap but I think I value bugproofing too heavily. The price, weight, and materials are right, but it's wide open. I have been to mosquito hell and back.

It's a pain that so many good bivy's aren't available. I wonder if this points to a flood of new designs in late 2013, before winter...

Bradford Rogers
(Mocs123) - MLife

Locale: Southeast Tennessee
Re: Most Breathable Bivy? on 03/04/2013 18:47:25 MST Print View

I dont want to tell you what you want or dont want, but I think at 6'-2" you would be happier with the regular trailstar than the compact version.

Secondly, you shouldn't need a bivy for weather protection with the trailstar as it has great protection itself. I think that if you wanted something for any slight spray or wind you would be better suited with a breathable top with DWR such as Pertex, Momentem, etc.

You might have problems with condensation in the humid east coast with a bivy and that will be even worse with a less breathable top like eVent or Gore Tex. Of course YMMV.

Max Dilthey
(mdilthey) - M

Locale: MaxTheCyclist.com
MLD "Endurance" Fabric? on 03/04/2013 18:52:01 MST Print View

Thanks Bradford. I'm on the same page as you on the Trailstar after talking about it previously in the thread. Also, I'm feeling you on that, but I got talked into eVent specifically. Do you think it's still significantly less than something like Pertex?

Does anyone know anything about the "Endurance" fabric MLD uses?

Jeffs Eleven
(WoodenWizard) - F

Locale: Greater Mt Tabor
Re: MLD "Endurance" Fabric? on 03/04/2013 18:57:53 MST Print View

Endurance IS Pertex

Endurance and Shield as WPB membranes from the Pertex company

Quantum is by Pertex also, but its a water resistant nylon, not waterPROOF

Max Dilthey
(mdilthey) - M

Locale: MaxTheCyclist.com
That solves it on 03/04/2013 19:12:41 MST Print View

MLD Superlight it is, then. Thanks, everyone! Much obliged!

Ryan Smith
(ViolentGreen) - M

Locale: Southeast
Re: Re: MLD "Endurance" Fabric? on 03/04/2013 20:14:56 MST Print View

Pretty sure MLD Endurance is not Pertex. I believe it's one of the iterations of M50, not a membrane fabric.

Ryan

Jeffs Eleven
(WoodenWizard) - F

Locale: Greater Mt Tabor
Re: Re: Re: MLD "Endurance" Fabric? on 03/04/2013 20:22:48 MST Print View

Well whoever named it needs to watch out:


http://www.pertex.com/fabrics/endurance/

Max Dilthey
(mdilthey) - M

Locale: MaxTheCyclist.com
Endurance? on 03/04/2013 20:41:21 MST Print View

Can anyone confirm one way or the other?

Edited by mdilthey on 03/04/2013 20:42:03 MST.

Jeffs Eleven
(WoodenWizard) - F

Locale: Greater Mt Tabor
Re: Endurance? on 03/04/2013 20:58:16 MST Print View

You're right 10X10 DWR nylon

I guess cause its not a membrane its not copyright infringement?

We can all learn something here LOL

Max Dilthey
(mdilthey) - M

Locale: MaxTheCyclist.com
I don't speak Cordura on 03/04/2013 21:08:52 MST Print View

What does that mean as a description of the fabric's qualities?

Jeffs Eleven
(WoodenWizard) - F

Locale: Greater Mt Tabor
Re: I don't speak Cordura on 03/04/2013 21:10:34 MST Print View

DWR not WPB

err sorry

water resistant, not a waterproof membrane

Max Dilthey
(mdilthey) - M

Locale: MaxTheCyclist.com
Aha on 03/04/2013 21:12:27 MST Print View

Similar to Pertex, gotcha.

Jeffs Eleven
(WoodenWizard) - F

Locale: Greater Mt Tabor
Re: Aha on 03/04/2013 21:15:15 MST Print View

Pertex is a brand

Similar to Pertex Quantum (i guess.. this is nearing the extent of my fabric knowledge. maybe more similar to Pertex Microlight... dunno)

steven franchuk
(Surf) - M
Re: Re: I don't speak Cordura on 03/04/2013 23:31:40 MST Print View

"Which fabrics are Water-Resistant/Breathable and which are Waterproof/Breathable. I know Pertex is the former and Goretex is the latter, any other examples worth knowing about? I'm fairly certain I want the former, since I'm using a tarp. I want the bathtub waterproof bottom (hopefully tough stuff) and a nice, light, water resistant top for wind spray and bugs. And good netted venting so I don't condense all over myself."

Keep in mind there are different types of "Breathable" and different levels of water resistance. For breathable fabrics you have vapor permeable and air permeable.

Vapor permeable fabrics have membranes that absorbs water like paper. The water once in the membrane works its way to the outside where it again turns to vapore and is carried off. Air however will not flow through it. Most WPB fabrics that use polyurethane membrane are only Vapor breathable and they typically don't breath much until interior humidity gets high. Breathability specs for polyurethane WPB fabrics are typically well below Event. Also you won't see a CFM rating for polyurethane WPB fabrics simply because air won't flow through the membrane. Pertex Shield is an example of this type of fabric. I don't think vapor permeable Membrane fabrics are a good choice for bivy's

Air permeable fabrics like event have very small holes that allow air and vapor through but don't allow or make it very hard for liquid water to get through. Event has a hydrostatic head of about 25,000mm and a CFM rating of 0.5 (If I remember correctly). If you increase the breathability (higher CFM)the hydrostatic head goes down. So when you get to ordinary fabric such as Momentum 50 your hydrostatic head goes to almost zero and the CFM ratting goes very high.

"I'm specifically buying this setup for conditions where my hammock is unusable due to high winds, intense rain, and the risk of falling branches. I am buying this for cold, wet, windy storms in the middle of clearings."

Momentum 50 and Momentum 90 DWR fabrics without membranes. bivys made from Momentum are designed for use under tarps to protect against water spray. But based on your concern of rain in windy conditions I think you are looking for something more than DWR fabric. A fabric with some hydrostatic head would be better. Event would meet your needs. There are some Event Bivys on the markets but most weigh more than your 16oz target.

Tyvek isn't waterproof but with a hydrostatic head of 850mm for 1443R makes it much more resistant to rain them Momentum and possibly good enough to meet your needs. There have been some post on the MYOG forum about tyvek bivys made from little more than Tyvek 1443R and Tyvek tape that weighed about 7oz.

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=46661 ).

Max Dilthey
(mdilthey) - M

Locale: MaxTheCyclist.com
I don't MYOG on 03/05/2013 05:11:06 MST Print View

I can barely sew, and I have no machine, so Tyvek is out. I feel like I'm right back where I started... Anyone have a recommendation for a Tyvek bivy or a first-hand experience with the MLD Superlight that contradicts the science?

Alex H
(abhitt) - MLife

Locale: southern appalachians or desert SW
Re: I don't MYOG on 03/05/2013 06:54:49 MST Print View

Dude, despite your claims that you do your research, you must not read all the posts above. Tyvek/Polypropolene bivy from Miles Gear

http://www.milesgear.com/UberBivy.html

And my experiences with a MLD superlight is condensation nearly 50% of the time

http://40yearsofwalking.wordpress.com/2011/07/04/the-bivy-condensation-conundrum/

a quote from my own piece:
"I have scoured the internet and there is no miracle fabric, all bivies have condensation/frost from time to time but the ones with the least mentions of condensation are made of all eVENT like the Integral Designs All eVENT bag cover (now discontinued) and the OR Advanced Bivy, both with vapor and air permeable top fabrics. [8, 9, 10]

The ones with a breathable nylon top with a good DWR and minimal silnylon floors, but without high bathtub floors, are the next best. From reports there seems to be something about the waterproof bathtub floors that leads to more condensation. This is apparently why the ones made of all eVent (top and bottom) have fewer reports of problems with condensation.

The worst offenders are any of the polyurethane membrane/WPB materials that are only vapor permeable like full Gore-Tex, Montbell DryTec, Mountain Hardware Conduit, etc. I have used or been around many of these and they all have had bad condensation problems.

One of the things that seems to happen with the vapor and air permeable fabrics (eVent, Gore-Tex FLO2, Gore-Tex Respiration Positive, Exchangelite and the less waterproof Gore-Tex Dryloft now Windstopper [10]) is that the membranes are laminated onto fabrics, and many lined with Tricot, that seem to help wick or pass the moisture through the material. I feel that this is why my old OR bivy had so few condensation problems, it has an almost cottony feel to it. The problem with these fabrics is they are heavier and the lightest of these bivies on the market are 13 oz. and up, with most around 18 oz. and they are crazy expensive ($200 plus)."