Bill Freeman wrote:

Hey Chuck,
You can buy teflon wiring for pennys per pound from Boeing Surplus. Hope  you
get back in the air soon.
Brian Trubee
Redmond, Wa

Is that actually teflon insulated wire or tefzel insulated wire?  About
10-12 yrs ago the military was switching from teflon to tefzel and
light planes were switching from PVC (very bad stuff!) to tefzel.
I haven't kept up since, but thought tefzel was the wave of the
future.  Teflon has somc cold flow problems and PVC makes
*extremely* nasty fumes when a wire fries.  I got a lungful
once and it was so incapacitating that I seriously doubt the ability to
maintain control of an aircraft with PVC fumes in the cockpit.
Apparently, tefzel is better and does not cold flow like teflon.

It would be interesting to test teflon vs tefzel for (external) fire
resistance and the "nastiness" of the fumes when you fry a wire.
I suspect this data is available somewhere.  What about some
fire sleeve over critical wiring like ignition and fuel injection?

Bill

Long EZ builder & pilot
mechanical engineer

I checked the temps and Tefzel is 150 C while Teflon is 200 C
or about 392 F. As long as the fire is not in the cockpit you
won't have to worry about fumes. If it is in the cockpit
you are in serious trouble needless to say.

Tefzel is also a lot more expensive than Teflon.
#16 Teflon is about 50 cents a foot.

You can buy real high temp wire (538C continuous) with a fiberglass
braid. Page 1221 Newark cat. http://www.newark.com 

#16 is about $2 a foot in 100 foot spools.

Fire sleeve is always a good idea. Back in the old days
they use to run critical wires through steel tubes.
 
Paul Lamar
 
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