KEEPING DRY
For some time I have been asked: What should I wear as a
rain garment, if the waterproofbreathable variety doesn't work? The answer
is multifaceted. We know that the only water we are to be concerned with
is that which we produce ourselves. Rain or melting snow can be kept out
if you wear a seam-sealed garment that is made with waterproof fabric,
such as a urethane-coated nylon. We know that all of the laminated film
material wets out, and therefore lets in water when the water-repellent
coating disappears.
Since we can not get rid of the moisture from the inside,
which we are responsible for, the best option is to stabilize it. This
would be in one of the layers of clothing we are wearing under the rain
garment. Temperature conditions will determine what those layers are.
If for example the temperature is +60 degrees or higher,
wear a long-sleeve cotton shirt. The cotton will absorb the moisture,
which is going to keep you cool. Remember the purpose of perspiring is to
keep the body cool. When the moisture coats the skin surface, it is
drawing heat from the body thereby regulating the core temperature. If you
wear a short-sleeve shirt, you will find that the garment wants to stick
to the skin. This is an uncomfortable feeling, or so it is for me. If the
rain garment is properly cut (size-wise), it will be billowy, and if you
keep the neckline open, a great deal of the moisture will escape.
If the temperature is below +60 degrees, the first layer
should be nylon fishnets. Now you do not want the moisture to collect on
the skin surface. If it does, when you stop your activity you will most
assuredly experience a chill. That is because the moisture is cooling you
faster than you are producing heat. The action of body-cooling occurs
regardless of the ambient air temperature. If the temperature is not lower
than +32 degrees, wear a cotton sweatshirt. It can be 100 percent cotton
or a cotton blend, but not less than 50 percent, if you want
water-absorption capability; and, finally, your rain jacket.
The moisture from the body goes through the large holes
in the fishnets and is absorbed by the cotton, where it is stabilized.
Your skin surface stays dry; therefore, you stay comfortable, warm. Again,
keep the collar open and a lot of the moisture as a vapor will escape.
Since I don't believe a fabric, an inanimate material
will ever be manufactured with the same functioning characteristics as the
human body has stabilizing perspiration is the only option.
Several years ago I started a project using input from
the Navy for underwear worn under a drysuit. The main problem is what to
do with the perspiration created by the diver. I learned that it is not
unusual for a diver to be down as much as 12 hours. Working underwater
takes considerably more effort than being on the ground. Not only is there
resistance from the water, but the drysuit is also cumbersome. Therefore,
you perspire a lot. Water builds up in the torso area and eventually runs
down and accumulates in the foot area. Imagine all of the water buildup in
the farthest extremity of the body. At this time the Navy is evaluating my
booties extensively. I believe they are thus far satisfied with them.
I studied their problem, and the solution is a
three-layer laminate of fishnet, Lamilite, and 100 percent cotton. The
fishnet against the skin allows the vapor to go to the Lamilite. Lamilite
does not inhibit the follow of moisture on its journey to the cotton
exterior where it condenses and is absorbed. Now none of the moisture has
opportunity the to run to the foot area of the suit. Warmer feet for the
diver.
An unexpected positive is when the diver comes out of the
water and deflates the suit. I was not aware that the suits were inflated
to begin with. Since the surface of the underwear touching the skin is
dry, the diver stays warmer out of the water as well. Keep in mind that
the air temperature above water is between 35-40 degrees colder than the
water, and can be as low as -30 degrees. If there is wind, well, we all
know about wind chill. I have supplied divers who go into Lake Michigan,
the Chicago River, Lake Erie, and the Atlantic off the coast of Maine.
They have all reported staying warm.
Stabilizing, trapping, or confining the moisture is all
you can do with it, just so long as it is kept away from the skin surface.
SLEEPING DRY
Many people ask how the Wiggy bags perform when
temperatures are above 40 degrees. The biggest problem in warm weather is
sweating in a sleeping bag. If you do, you will wake as easily as when you
are cold. The reason is simple: you become clammy. This is a very rare
occurrence with a Wiggy bag. The vapor permeability of the lining fabric
that I use allows the moisture as vapor to easily escape into the fiber.
The fiber has shown that it does not restrict this flow of moisture
either. Therefore, you stay dry even in warm weather.
Almost all of the high-priced sleeping-bag manufacturers
use very tightly woven fabric for the lining as well as the shell of their
bags. This type of fabric is very necessary if the fill is down or a fine
denier, silicone-treated polyester fiber. In some instances the fabric is
"calendered." To calender a fabric, you squeeze it between two rollers,
one hot and the other cold, or room temperature. The heated roller melts
the yarns together to some degree. They are fused. This is commonly done
to "down proof" fabric. It is equally necessary to inhibit fiber migration
of fine denier fiber. The end result is a fabric that loses its
vapor-permeability. Therefore, in warm conditions you are apt to
experience clamminess in bags made with these types of fabric.
A QUICK TALE
The following story came to me via e-mail. The writer is
Ted. He lives in Northwest Washington State.
"A few years ago my brother and I went hiking too early
in the season. We went to one of our favorite lakes in northwest
Washington. Our campsite was on the opposite side of the lake. We carried
high-tech 2-1/2 pound rafts for fishing and blew them up to raft across
the lake. The camp is 2-1/2 miles down the lake in the rafts, and right in
the middle of the lake we look towards the outfall end to see clouds
piling into the lake; a freak bit of bad weather rolling in. Soon the
clouds fill the lake basin and we cannot see 10 yards around us. Then it
began to rain. Hard. Really Hard. Temperature dropped from 45 to 35
degrees in a matter of minutes. The wind blew so hard waves washed into
the rafts who knows what the wind chill factor was. We rowed around in
circles for an hour, then got out a compass and headed for our camp.
Another hour goes by, we hit the beach with a few inches of water in the
rafts and all gear soaked. All we had brought was hooped bivy sacks for
shelter, and Wiggy bags. My brother was so cold he was shaking, borderline
hypothermic, and too incoherant to untie his boots. I got his bivy out,
wrung out the Wiggy bag and stuffed it into the sack. Then I helped him
undress and zipped him into the bag. I got into my bivy and bag after
undressing and just listened to the rain come down until I finally went to
sleep. Next morning I peeked out of the bivy to see my brother's clothes
covered in snow. Our Wiggy bags were dry and we were warm all night. I
don't know what would have happened if those bags were down. I don't want
to know. I've never used down since then. Not worth it for a few
ounces."
If any one wants to contact Ted, let me know and I'll
give you his e-mail address.
Did you ever hear the expression "live and learn"? When I
first started making sleeping bags I only knew how to make them and what
they were used for. Characteristics such as holding heat when the fiber
gets wet were things I have learned about over the years. Did I know how
well the Lamilite would perform in conditions such Ted describes? No. I am
pleased to say I have learned a lot from my customers, whose information I
have passed on to you in product improvements for your comfort in the
field.
MILITARY ISSUE
In the November newsletter I wrote about the poor
performance of the sleeping bag system the military is issuing to the
field troops. I have received a large number of calls and e-mail messages
from members of all branches of service, non-comms as well as officers
complaining about the poor quality and poor performance of the issue MSB
(Modular Sleep Bag). All of these people thought they were being issued
the Wiggy FTRSS. They buy them with their own funds.
One officer located in Alaska had this to say about the
MSB: "The MSB is a piece of S---! The MSB we got is black outside and a
thin green inside a green bag. The hood is terrible--you cannot put it
over your head like the old bag. Your head sticks out and you know how you
are losing heat. The major problem is, it does not breathe! I woke up with
ice on the inside of my bag and it was only 20 degrees. I was freezing!
It's light and it goes easily into a stuff sack. Everyone has gone back to
the old bag. I use my MSB as a ground cover. They issued us a Gortex cover
that helped a little--the ice problem continued. It's probably a great bag
at 10 to 30 degrees."
I am sorry to say this officer's comment can be repeated
over and over again. I am happy to say that there are more and more units
are going outside of the system to get personal equipment for the
troops.