bordertangoman
05-07-2010, 05:53 AM
THE MYTH OF WICKING
There is a lot of pseudo-science surrounding the subject of "wicking". Let's be clear about this. A "wick" is a strip of fabric made of organic fibres such as cotton, linen or hemp, used in oil lamps. Oil is sucked up by the porous fibres from the pool of oil. When the synthetic manufacturers needed to describe the process by which their synthetic clothing dried, they obviously felt that the term "drip" (for this is what it really does) was not suitable for their advertising campaigns, and so they came up with the idea of turning the noun "wick" into a new verb - "to wick".
The problem is that most oil-based synthetics cannot "wick" in any sense of the word as they are incapable of absorbing moisture, any more in fact that a plastic washing up bowl. They are non-porous. Moisture only moves through synthetic clothing by virtue of the knit construction. This ensures that the lines of knitting slope outwards, and gravity does the rest - dripping!
Merino, like all wools, actually absorbs moisture, and then sheds it gradually to its outer surface. This is "wicking". No synthetic can do it - only attempt an approximation of it.
There are cellulose-based fabrics coming on to the market now, bamboo being one, however these can absorb far too much moisture and then hang on to it, creating a cold wet garment that can add to the dangers of hyperthermia for the wearer. For use for hot (dry) weather garments, these fabrics may be fine, but they are not suitable for all-round, all-weather, garments.
There is a commonly held belief that a wicking base layer will stop your clothing becoming damp and sweaty. This is not necessarily true. It depends on what you are wearing on top of your baselayer.
When you work hard your body produces perspiration to help you keep cool. If you are stark naked, this sweat normally evaporates from the surface of your skin. If you are wearing a single layer of absorbent clothing, the sweat will be absorbed by this layer, and eventually evaporate into the atmosphere if it is warm enough. When you stop working hard, or just slow down a bit, and start to cool down, the absorbent layer you are wearing will become cold and damp next to your skin.
A "wicking" garment is supposed to pass the perspiration through from your skin to the next clothing layer. However it can only pass it from its own inner surface to its own outer surface. Each succeeding layer must do it's own job of passing on the perspiration to the next layer until it eventually gets to the outer surface and is passed into the atmosphere. If one of these intermediate layers is absorbent it will absorb the perspiration as well as passing it on - but only "if". As we said before, synthetic fibres do not absorb moisture. They "drip". Their interlock construction allows moisture to trickle down through the gaps.
You can therefore have the situation of wearing high performance wicking underwear giving you a dry comfortable skin but your cotton or synthetic midlayer is very damp under your breathable jacket, making you feel cold - and possibly giving you wet feet!
For maximum performance wicking underwear requires a middle layer which will wick at a similar rate and an outer layer capable of passing the perspiration rapidly to the atmosphere. Because of merino's ability to both absorb and shed moisture, and because of its ability to keep you warm even when wet, it makes an ideal base layer and mid layer under any outer layer."
http://www.chocolatefishmerino.co.uk/technical/wicking.html
There is a lot of pseudo-science surrounding the subject of "wicking". Let's be clear about this. A "wick" is a strip of fabric made of organic fibres such as cotton, linen or hemp, used in oil lamps. Oil is sucked up by the porous fibres from the pool of oil. When the synthetic manufacturers needed to describe the process by which their synthetic clothing dried, they obviously felt that the term "drip" (for this is what it really does) was not suitable for their advertising campaigns, and so they came up with the idea of turning the noun "wick" into a new verb - "to wick".
The problem is that most oil-based synthetics cannot "wick" in any sense of the word as they are incapable of absorbing moisture, any more in fact that a plastic washing up bowl. They are non-porous. Moisture only moves through synthetic clothing by virtue of the knit construction. This ensures that the lines of knitting slope outwards, and gravity does the rest - dripping!
Merino, like all wools, actually absorbs moisture, and then sheds it gradually to its outer surface. This is "wicking". No synthetic can do it - only attempt an approximation of it.
There are cellulose-based fabrics coming on to the market now, bamboo being one, however these can absorb far too much moisture and then hang on to it, creating a cold wet garment that can add to the dangers of hyperthermia for the wearer. For use for hot (dry) weather garments, these fabrics may be fine, but they are not suitable for all-round, all-weather, garments.
There is a commonly held belief that a wicking base layer will stop your clothing becoming damp and sweaty. This is not necessarily true. It depends on what you are wearing on top of your baselayer.
When you work hard your body produces perspiration to help you keep cool. If you are stark naked, this sweat normally evaporates from the surface of your skin. If you are wearing a single layer of absorbent clothing, the sweat will be absorbed by this layer, and eventually evaporate into the atmosphere if it is warm enough. When you stop working hard, or just slow down a bit, and start to cool down, the absorbent layer you are wearing will become cold and damp next to your skin.
A "wicking" garment is supposed to pass the perspiration through from your skin to the next clothing layer. However it can only pass it from its own inner surface to its own outer surface. Each succeeding layer must do it's own job of passing on the perspiration to the next layer until it eventually gets to the outer surface and is passed into the atmosphere. If one of these intermediate layers is absorbent it will absorb the perspiration as well as passing it on - but only "if". As we said before, synthetic fibres do not absorb moisture. They "drip". Their interlock construction allows moisture to trickle down through the gaps.
You can therefore have the situation of wearing high performance wicking underwear giving you a dry comfortable skin but your cotton or synthetic midlayer is very damp under your breathable jacket, making you feel cold - and possibly giving you wet feet!
For maximum performance wicking underwear requires a middle layer which will wick at a similar rate and an outer layer capable of passing the perspiration rapidly to the atmosphere. Because of merino's ability to both absorb and shed moisture, and because of its ability to keep you warm even when wet, it makes an ideal base layer and mid layer under any outer layer."
http://www.chocolatefishmerino.co.uk/technical/wicking.html