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Sonno
01-15-2011, 13:50
Ok...

Down comes from Ducks and Geese, correct? And it works for you the same as it does the bird; it keeps you warm by trapping an abundance of body heat within its tiny clusters. And because it is also breathable, down allows unwanted moisture to escape.

However, it also looses its insulating properties when it is wet and is slow to dry. Right?


Well...

Don't Ducks and Geese live on the water??? Why don't we have a bunch of dead hypothermic ducks floating around?

skinewmexico
01-15-2011, 13:53
It loses some of it's insulating properties when wet. So do synthetics. Down loses more though. You have to work to get down wet, if you prepare.

Tuckahoe
01-15-2011, 14:07
Ducks and geese are able to coat their feathers with oil from a gland.

Luddite
01-15-2011, 14:21
Ducks and geese are able to coat their feathers with oil from a gland.

And they fly south for the winter.

Sonno
01-15-2011, 14:40
I am in the south! :D

wrongway_08
01-15-2011, 14:46
Then coat yourself in oil and problem solved!!! :)

Tinker
01-15-2011, 16:25
Down is the bird's insulating layer. It isn't waterproof. The outer layer of feathers is well oiled and waterproof. The down is under the waterproof layer.

bigcranky
01-15-2011, 16:36
What Tinker said.

Luddite
01-15-2011, 16:41
Another advantage a duck has is the ability to shake the water off.

Sonno
01-15-2011, 16:43
I guess that makes more sense...

Luddite
01-15-2011, 16:47
http://www.thenakedscientists.com/HTML/content/latest-questions/question/1553/

Ducks have very little muscle in their feet, mainly tendons. This means that the muscle which makes them move is further from the feet and better insulated, and there's less in the feet to keep warm. Ducks also have a very clever circulation system, where warm blood going down to the feet goes closely past the cold blood coming back from the feet. This is called a counter-current heat exchange as heat is exchanged from the hot blood to the cold, meaning that the birds do not lose too much heat through their feet.

There is some suggestion that they also make an anti-freeze compound in their feet called Ethylene Glycol, which stops the blood in their feet from freezing by lowering it's freezing temperature. Natural anti-freeze chemicals are often seen in fish that live in freezing waters.

chiefiepoo
01-15-2011, 16:49
Then coat yourself in oil and problem solved!!! :)
BP tried that on us down here, didn't look very fashionable. Ducks and geese said, no thanks, they were good.

Tinker
01-15-2011, 16:53
One more note of clarification: Down is thoroughly washed to remove most of the oil which comes from the bird, so the down in your bag or clothing has much more loft than it ever did on the bird.
The fill power is measured by putting a measured weight of down in a cylinder and compressing it with a weight (not sure how much). The higher the fill power, the less the down gets compressed under the weight, so the more space an ounce of it will fill the available space in the garment or sleeping bag.
Strangely, many garment manufacturers use a high fill power down in "ultralight" garments and then put so many rows of stitches in them that the down cannot loft to its maximum potential. The use of baffles increases the effectiveness of whatever down quality is used in the garment or sleeping bag. Most quality down sleeping bags are baffled. Most ultralight down clothing is not. Women's models, often sewn for fashion's sake sacrifice the fillpower of the down for the style, vs. men's garments which usually have the blocky, linear stitching. Unfortunate, but true.

Wise Old Owl
01-15-2011, 19:51
Well the guys covered this well in in fish oil, the ducks are satisfied...

except this..."down allows unwanted moisture to escape."

Nope it clings to it.... one has to air out the bag each morning, this is why the bags come with a little loop at the toe box for hanging.