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Cotton Kills - Page 4

post #91 of 113
Thanks, much appreciated.

OOPPS, this is a subscription required article.
post #92 of 113
Thanks Finndog for your very good input. A few additional comments/questions.

1) Absorption not the same as retention? My guess is that a fabric's tendency to absorb moisture is closely related to it's tendency to retain moisture.

3) The process of evaporation does requires heat, heat is used, or absorbed, in the conversion of liquid to vapor.

4) I always figured the absorption of water depended more on the fiber's molecular properties rather than it's smoothness. Would very smooth cotton work better as a base layer than very rough polyester?

Heat loss from cotton. Due to cotton's tendency to absorb and retain water, my guess is more body heat is lost through wet cotton from conduction rather than evaporation.

With quick drying fibers, some heat maybe lost through evaporation but the hydrophilic nature of the fiber will keep conductive heat loss to a minimum.

Wool is pretty absorbent but remains insulating. So this kind of shoots down my theory that the insulating value of fibers in a wet enviroment is directly related to the amount of water held in the cloth. What's up with wool?

I would read your links, but I prefer to form my opinions in a void, and hold on to them firmly until presented with strong evidence that I'm wrong.
post #93 of 113
Here's some information about the properties of wool that may shed some light on why it "feels" warmer when wet (credit goes to Backpackinglight.com):

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To understand the properties of Merino wool fabrics you must first understand the structure and properties of wool fibers. Unlike synthetics, which have a uniform composition inside and out (i.e. it’s a hunk of plastic that may be shaped), individual wool fibers have an exterior scaly sheath, enclosing bundles of interior fibers (see photo 3). The surface of each fiber is hydrophobic (repels moisture), helping to repel water off the surface of the fabric.


Because of the complex internal structure of wool fibers, and the fact that the interior portion of the fiber is hydrophilic (attracts moisture), water can be absorbed INTO the fibers of a wool fabric, whereas in synthetic fabrics water is only held in the spaces between individual fibers since the fibers themselves do not absorb water. Merino wool fibers can absorb approximately 30 percent of their weight in water. Synthetic fibers themselves will not absorb any water. This means that wool fabrics will hold more moisture than synthetics and will take longer to dry. But in a wool fabric the water is stored away from the surface, and consequently a wool garment may not feel so clammy next to your skin when wet.
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Note that cotton, like wool and unlike synthetics, absorbs water into its fibers themselves. However, it doesn't have the scaly outer structure of a wool fiber to help keep the water from contacting the skin.
post #94 of 113
Quote:
Originally Posted by telerod15 View Post
Thanks Finndog for your very good input. A few additional comments/questions.

1) Absorption not the same as retention? My guess is that a fabric's tendency to absorb moisture is closely related to it's tendency to retain moisture.

4) I always figured the absorption of water depended more on the fiber's molecular properties rather than it's smoothness. Would very smooth cotton work better as a base layer than very rough polyester?
1 - True. Absorption and retention are closely related. Adsorption and retention are inversely related. See what I posted above.

4 - True. It has nothing to do with smoothness.
post #95 of 113
Quote:
Originally Posted by Harry_Morgan View Post
1 - True. Absorption and retention are closely related. Adsorption and retention are inversely related. See what I posted above.

4 - True. It has nothing to do with smoothness.
Thanks, your post about absorption vs. adsorption was very helpful in understanding wicking.

Taking the question of smoothness one step further, does the insulating value of wet wool have something to do with wool's coarse texture?
post #96 of 113
Quote:
Originally Posted by Finndog View Post
water will not hold your temperature well at all, as soon as it's exposed to cold temps or winds, the temp of the water will fall rapidly.
You're confusing two concepts - whether the water holds heat or whether water cools you. Water holds heat well, having a high specific heat capacity, but doesn't insulate you because it is an excellent conductor, and because the latent heat of vaporization is high.

Quote:
Originally Posted by Finndog View Post
you lost me on the water surface ratio as compared to cotton. Cotton is avery fibrous material with huge surface areas that will hold moisture molecules and not effectively transconduct them. Essentially, its a sponge.
Cotton absorps the water, so the water is "in" the cotton. Polyester does not, so a much thinner film of water will be present "on" the fiber. The thinner layer on the polester will evaporate much more quickly than the water in the cotton.
post #97 of 113
Quote:
Originally Posted by sibhusky View Post
So, the conclusion is what?

Please, all you experts, list what to where in what order, for a day when the fog is freezing onto your coat or its raining and there is this layer of ice or wetness on the top layer, thereby interfering with the sweat vapor passing to the air outside. The vapor is going to stop moving away from your body somewhere it seems to me.

You are the expert. You are out in the damp cold weird frozen humidity. You've been found off trail unconscious and presumably not hypothermic. Keep rocking the cowl neck girl, you know what works for you.
post #98 of 113
Quote:
Originally Posted by telerod15 View Post
You are the expert. You are out in the damp cold weird frozen humidity. You've been found off trail unconscious and presumably not hypothermic. Keep rocking the cowl neck girl, you know what works for you.
I was asking for a conclusion. Thanks for the help.

I haven't seen the conclusion yet, just a lot of discussion about the very inside layer.
post #99 of 113
Quote:
Originally Posted by Harry_Morgan View Post
You're confusing two concepts - whether the water holds heat or whether water cools you. Water holds heat well, having a high specific heat capacity, but doesn't insulate you because it is an excellent conductor, and because the latent heat of vaporization is high.

Cotton absorps the water, so the water is "in" the cotton. Polyester does not, so a much thinner film of water will be present "on" the fiber. The thinner layer on the polester will evaporate much more quickly than the water in the cotton.
Correct. The issue with cotton is that the fiber itself absorps the water, and does not release it without a significant input of heat. Synthetic fabrics are more similar to a sponge in this example, in that they hold water via capillary action in the spaces between their fibers, but not inside the fibers. Hence, the total volume of water absorbed by a synthetic fabric will be much less. Manufacturers can process or treat a synthetic fiber to improve its ability to move water. This is typically done by adding texture to the surface of the synthetic fibers, or changing the cross-sectional shape of the fibers, or applying a chemical finish. This texture or finish increases surface complexity, making it more hydrophilic. The objective of these shape modifications is to speed movement of water along individual fibers, away from your skin and dispersing the moisture closer to the outer surface where it will evaporate more quickly.
post #100 of 113
Quote:
Originally Posted by sibhusky View Post
I was asking for a conclusion. Thanks for the help.
Your welcome. Read the thread and make your own conclusion. There is a lot of good info here. I'm concluding that synthetics are the best fabrics to avoid hypothemia and death. Wool is next best and silk is better than cotton or hemp.
post #101 of 113
Quote:
Originally Posted by sibhusky View Post
I was asking for a conclusion. Thanks for the help.

I haven't seen the conclusion yet, just a lot of discussion about the very inside layer.
I'm not sure if there is an ideal set of clothing that will perform optimally in those conditions. The freezing fog you describe is probably the most difficult environment to dress for, and you correctly point out that no outer layer is going to breathe once it gets saturated or coated with ice. In my experience, what has worked is dressing as I would for that specific temperature -- synthetic base layer, fleece insulating layer -- and covering those with a waterproof/breatable hardshell to avoid soaking the insulation. Then, I'd be extra-careful to regulate my exertion to avoid excessive sweating, which would have nowhere to go. Once the weather improved, hopefully, my body heat would begin to dry out any sweat in the inner layers, and the fog/ice on the outer shell would start to melt off and dry out.
post #102 of 113
Quote:
Originally Posted by MRGSingleChair View Post
Note that cotton, like wool and unlike synthetics, absorbs water into its fibers themselves. However, it doesn't have the scaly outer structure of a wool fiber to help keep the water from contacting the skin.
This thread has gotten quite interesting, and I found this particular comment particularly intriguing. Found this page looking for a magnified photo.
post #103 of 113
Don't overdress is great advice. Avoid sweating in the winter. Take off a layer. Be proactive. Open vents before descending, close them before boarding lift. If you wait until you are hot to unzip and wait until you are cold to zip up, you will find yourself closing zippers towards the top of the lift ride and opening them at the loading area. Opposite of what you should do.
post #104 of 113
Quote:
Originally Posted by MRGSingleChair View Post
I'm not sure if there is an ideal set of clothing that will perform optimally in those conditions. The freezing fog you describe is probably the most difficult environment to dress for, and you correctly point out that no outer layer is going to breathe once it gets saturated or coated with ice. In my experience, what has worked is dressing as I would for that specific temperature -- synthetic base layer, fleece insulating layer -- and covering those with a waterproof/breatable hardshell to avoid soaking the insulation. Then, I'd be extra-careful to regulate my exertion to avoid excessive sweating, which would have nowhere to go. Once the weather improved, hopefully, my body heat would begin to dry out any sweat in the inner layers, and the fog/ice on the outer shell would start to melt off and dry out.
It sounds like that insulating layer is key. I'd need to make sure that the insulating layer wouldn't be retaining moisture and that it was closer to my skin than the layer that would be now the "roof" for the vapor. Right? So, IF I INSISTED ON WEARING COTTON FOR WHATEVER REASON, having a microfleece layer like the Hot Chilis would make a big difference if it was between me and the cotton, especially if under the Hot Chilis there was something like two layers of Thermax. Removing the cotton might in fact warm me up, IF it was happening that it was found to be damp at any time. If it was not damp, that would pretty much indicate that it was also acting as insulation. So, the thing to do is check the cotton on these days to figure out if it is helping or hurting.
post #105 of 113
Here's a diagram of a wool fiber from that article I mentioned:



and the caption:
Photo 3. The internal structure of a single wool fiber is a complex matrix consisting of numerous bundles of sub-fibers. Water can be absorbed into this internal matrix and then released again.

I've always found lift-served skiing to be difficult to dress for. If I'm warm enough sitting on the freezing chairlift, I'm often too warm while working my way downhill. While I've never tried the new merino base layers, I'm curious whether their heat retention properties might help mediate this hot/cold cycle. Synthetics always give me a bit of a chill once I get on the chair.
post #106 of 113
Thanks for that pic. I'd love to try merino long underwear. Anyone try the Smartwool brand? I like their socks...
post #107 of 113
Quote:
Originally Posted by sibhusky View Post
It sounds like that insulating layer is key. I'd need to make sure that the insulating layer wouldn't be retaining moisture and that it was closer to my skin than the layer that would be now the "roof" for the vapor. Right? So, IF I INSISTED ON WEARING COTTON FOR WHATEVER REASON, having a microfleece layer like the Hot Chilis would make a big difference if it was between me and the cotton, especially if under the Hot Chilis there was something like two layers of Thermax. Removing the cotton might in fact warm me up, IF it was happening that it was found to be damp at any time. If it was not damp, that would pretty much indicate that it was also acting as insulation. So, the thing to do is check the cotton on these days to figure out if it is helping or hurting.
Right. The insulating layer is definitely important, but I find I'm most comfortable when I pick layers and shells that work together and help to move the moisture without it getting too stuck at any particular layer. While the cotton layer in you example would provide some insulation while it's dry, in most skiing situations I'd guess you'd sweat at least a little bit and the cotton would start to absorb that moisture. If you took it off once it started to get wet you'd preserve your insulation system, but past that point I'd expect that the cotton would start to cool you off. For lift-served skiing this probably isn't a big deal, since you can just hit the lodge to drop the wet layer, but any situation where I'd be outside for a long stretch I'd just leave the cotton at home.
post #108 of 113
Duofold is nice. Cotton against the skin to prevent itching, wool on the outer side, hence "duofold" two materials together in one. Long underwear to keep you comfortable and warm.
post #109 of 113
How many layers do people wear when skiing the lift served anyways? I'm usually at two layers on most days, base and shell, maybe a fleece vest for single digits, and if its below zero and windy I'll wear a full fleece between the shell and base layer. I'm probably royally screwed if I get stuck in a ditch overnight, but I don't get how people can ski with all those layers and not sweat themselves silly.
post #110 of 113
Usually start out with three layers maybe ditch the shell or middle layer if it warms up. Three warm layers is it's very cold, three thin layers if it's not.
post #111 of 113
Quote:
Originally Posted by skiingman View Post
How many layers do people wear when skiing the lift served anyways? I'm usually at two layers on most days, base and shell, maybe a fleece vest for single digits, and if its below zero and windy I'll wear a full fleece between the shell and base layer. I'm probably royally screwed if I get stuck in a ditch overnight, but I don't get how people can ski with all those layers and not sweat themselves silly.
For lift-served in northern Vermont, where I typically ski, I usually keep it pretty simple -- midweight capilene base layer, medium weight fleece mid layer, and a softshell on top. I really like the softshell since it breathes so much better than a hardshell, and helps keep me drier. For really cold days I'll add another fleece. If it's raining/sleet/hail/semi-frozen VT death fog and I'm stupid enough to keep skiing, I'll switch to a waterproof hardshell to stay drier. If it's one of those -30F VT days, I'd probably wear my down parka over everything else until I realized all the smart people were drinking in the lodge and then I'd go join them.

On my legs I keep it to synth boxers and a thicker long underwear under a hardshell for all but the coldest days. I'd probably not survive the ditch either, but I'd be comfy until then.
post #112 of 113
I run cold even in summer (sleep under a down quilt all summer), so the past season (had stuff cut off me, so now must replace all of that) had on top: two layers of Thermax (days under 25 degrees), one layer of Hot Chili (days under 15 degrees), one layer of cotton (all the time for the neck thing), one polarteck underjacket most days, and one Goretex XCR hard shell. On days below 10 degrees if there was any wind, I'd throw on an Eddie Bauer minus 40 degree down coat in place of the Goretex and polartec. If it was below zero, the Eddie Bauer would go over the Goretex and polartec.

On bottom, two layers of Thermax and insultated Spyder pants.

Bootgloves on days below 25.
post #113 of 113
Quote:
Originally Posted by Trotski View Post
Hey, I had a question: what wool ISN'T "merino?" I thought that Merino sheep were by far the most common sheep in the world?
Merino is a specific breed of sheep raised for the quality of its wool. It is one of the most common breeds in Australia & New Zealand. For those who avoid "itchy" wool there are some things to know to avoid that itch & contact dermititis. There are extreme differences amongst & within the breeds. The best wool is measured by microns, the diameter of the shaft of the fiber/hair of the wool. The smaller the better & softer for undergarments. This is a quality bred into the Merino & a number of the nordic sheep, ex. the Finn wool sheep. One of the processes that can keep wool garments from itching as well as felting & shrinking is a "superwash" utilizing chemicals that remove the "outter scales". Thus removing all the "itch" factor (absent of a true allergy).
The wool industry in America has not until recent times, used a fine quality of wool & thus well known brands have always been itchy. I've been using base layers of wool for winter work outside for 5 yrs. But were imported from Finland. Now the U.S. market has finally caught on & using the merino wool & some superwashing to market our new wool base layers.
I like the wool best & own several different weights. I NEVER get cold when wearing them,even with a cotton turtleneck over & Goretex rain coat on top. But then again, I'm in the Sierras which for skiing didn't get cold this year. The best quality about wool, is the air it traps within the yarn. And it is a protein fiber like silk so both repel odor well. Sorry for the length here, I spin & knit so fiber is something I can get into (a bit much).
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