Some heretical views on cold weather clothing

[Rayleigh_Scattering]

Cabelas is hiring part time staff, which suggest to me that many others (like me) are thinking about outdoor clothing for the cold season.

For your amusement I attach a link to a DRDC report from a DND scientist whoose job it was to test and evaluate cold weather clothing in the 1990s.

Your tax dollars paid for it (assuming you are old enough), and there's some really good basic physics here even if you skip over the math. Thereès a heavy layer of sales-BS covering everything at the store. Rivet on a handle onto an 18" section of this knowlege and use it to hack your way through at least some of that.

http://cradpdf.drdc-rddc.gc.ca/PDFS/unc112/p48076_A1b.pdf

This is a general paper on heat transport in clothing. Highlights are:

-Cold Goretex works about as well as a plastic bag
-All mostly-dry fibers (wring them out) of the same thickness transmit heat at about the same rate.
-Layer-to-layer wicking could not be demonstrated in any realistic heatépressure situation.
-Water vapour transport and condensation are a major complicator, and it gets worse once the outler layer drops below zero and water starts to condense as frost inside your clothing/sleeping-bag.
-Water repellent coatings, assuming they didn`t come off the first time you wash the item, make a major difference to insulation performance by reducing the weight of absorbed water.

The hard problem, he says, is not keeping the user warm. It is adapting to the widely differing thermal power and water transport issues caused by human activity cycles (80W and dry when asleep, 10x that and sweating at max effort). That's what takes the time and effort to get right.

There's a bunch more from the same author, all of which I found both educational and entertaining.

 

[vagrantviking]

Interesting findings. Thanks for the synopsis.

Always suspected that some of much hyped wonder products were of dubious value in many situations.

 

[bcsteve]

Interesting but I’m sure some of the textile technology has also changed since 1985.

 

[Big Bad]

Goretex works in deep cold, let's say about a thousand times better than plastic, but you have to work with it. For instance, there's a reason quality goretex items are made ventable. And as bcsteve suggests, Goretex was indeed just coming on the market in 1985 and it was in fact pretty nasty stuff to wear, not like now.

 

[woodchopper]

having lived the experience of crappy military kit over the decades the current stuff is lightyears ahead of what we had in the late 80's

layering up and removing layers is important.

Like gutting a moose at -20C, I tend to be down to just my t-shirt for that exercise.

most of the overpriced super fabrics are not really worth it for me.

fleece, gortex, and wool are my go to fabrics.

 

[Rayleigh_Scattering]

Regarding the water angle, this paper called "The interaction of Fabrics with Water" puts a better base under it (at the cost of it being a bit thicker to get through).

http://cradpdf.drdc-rddc.gc.ca/PDFS/zbb63/p508780.pdf

Educational stuff if you can spend the time to absorb it (or adsorb it Ha!)

 

[northern skies]

Cool, I'll read that.

On topic, I discovered vapor-barrier liners last winter. Blew my mind.

 

[Rayleigh_Scattering]

>vapour barrier

For sleeping bags, you mean?

 

[northern skies]

The socks. My feet have never been so warm in such light boots.

Same principle as the sleeping bag thing. I read about it in one of Andrew Skurka's articles, and gave it a try. He actually used a whole-body VBL one one of his treks.

 

[blasted_saber]

The socks. My feet have never been so warm in such light boots.

Same principle as the sleeping bag thing. I read about it in one of Andrew Skurka's articles, and gave it a try. He actually used a whole-body VBL one one of his treks.

Do you have a brand name I could google?

 

[bearkilr]

Do you have a brand name I could google?

You can use a bread bag or kitchen garbage bag, similar idea. Put on a wool sock, then plastic/vapour barrier, then another sock. It's supposed to keep your boot liners from getting sweat/moisture on them.

 

[northern skies]

^^^This. That's what I tried first to check the concept out. They ripped after 30mins of x-c skiing. Then I got some good silnylon ones at mec.

I use a thin synthetic liner sock, then the VBL, then an appropriate weight of wool sock over top for insulation. Basicaaly, it just keeps the wool sock dry when your feet get sweaty. I don't get that super-chill when I stop moving anymore.