[TheForge] OT Urethane foam. was inflatable castle

Fri Mar 19 13:22:01 2004

I suspect the chemistry of polyurethane foam could be altered to meet the =
challenge.

But maybe there's an alternative.  All you need do is fill space and =
restrict convection.

Back to double-wall idea (inflatable structure), but fill space with some =
bubbling substance that neither hardens nor freezes.  Like alcohol-based =
soapsuds.  But long-lasting.  Would need to identify such a substance.  =
Use a pump to generate both inflation and suds.

Bruce
NJ

>>> [email protected] 3/19/2004 12:24:11 PM >>>
Down is a poor choice, it loses about 95% of it's insulating properties =
when
wet, of course modern synthetics don't suffer this limitation and in cold
country you only see down in comforters any more.

Regardless, you need shelter against the weather. I have a bag rated
for -140f (no typo) and though it would keep you warm almost anywhere on
earth if you tried sleeping in the open wind driven snow would entomb and
suffocate you. Wind drifted snow can be hard enough to drive a dump truck
over.

Urethane is temperature sensitive, much below 50f and it takes forever to
set and doesn't expand to capacity.

Directing a foam into a suitable shape is easy enough, a double wall with
ties between the walls to keep a proper thickness works fine. A spray
application won't work unless the conditions are ideal in which case you
wouldn't need a fast construction technique.

The system would also need to be small and light enough small plane pilots
wouldn't have to sacrifice much cargo space and weight.

Frosty
------------------------
If it ain't forged
it ain't real.
Wrought iron is.
The FrostWorks

Meadow Lakes, AK.

----- Original Message -----
From: "Bruce Freeman" <[email protected]>
To: <[email protected]>
Sent: Friday, March 19, 2004 5:56 AM
Subject: [TheForge] OT Urethane foam. was inflatable castle

I haven't read up on urethane foam.  I take it the commercial stuff =
doesn't
work at low temperatures?

There's probably an easy fix.  Encorporate an exothermic reaction in the
mix, somehow.  Shake the bottle, hit the trigger and out comes warm liquid
(like "Great Stuff" =AE)) that foams and sets.

Now, how to direct the stuff into a useful shelter form.

Wouldn't a down sleeping bag be easier?

Bruce
NJ

>>> [email protected] 3/18/2004 4:33:30 PM >>>

----- Original Message -----
From: "Bruce Freeman" <[email protected]>
To: <[email protected]>
Sent: Thursday, March 18, 2004 11:31 AM
Subject: RE: [TheForge] inflatable castle

As I'm sure I've bored everyone here with the telling, I used to live =
nearly
year round in a tent on the job. And while the market in large inflatable
structures may have early entrants there is still the small structure
market. Tents.

You just haven't lived if you haven't had to set up a tent in a sleet =
storm.
I don't know how many times I wished for my old Coleman "Pop Tent" even
though it was about as water proof as a cheap blanket. What I designed
instead was a tent with inflatable "poles". It had an integral rain fly,
floor, bug netting, windows and even a stovepipe jack.

I intended it to be inflated with bottled nitrogen for it's low coefficient=

of expansion (thermal). Of course a person could use a hand pump if =
there's
no hurry but being able to just toss the thing on the ground and pull a
trigger is a major draw in foul weather.

So Bruce, while there're already dogs in the large inflatable structures
race, I think there's still a place for the small ones. Lastly, here's
something for the chemist in you. If you can come up with an insulating =
foam
like urethane that will react and set quickly in sub-zero temps you could
save many lives with self inflating emergency shelters.

Frosty
------------------------
If it ain't forged
it ain't real.
Wrought iron is.
The FrostWorks

Meadow Lakes, AK.

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