"Del Rawlins" wrote in message
...
In Richard Lamb wrote:
Del Rawlins wrote:

Butyrate shrinks quite a bit.
Even the "non-taughtening" variety pulls up a bit.

So a glass skin would rely on the coating for taughtness
(not in the MS dictonary?) - just like linen does.

I thought that the natural fiber coverings like linen or cotton were
primarily shrunk using water? I.E. they get most of their tautness from
natural shrinkage as the water dries, prior to the coating being applied.
Or am I all wet? I don't know a lot about fabric covering and am just
trying to get a clear understanding of the various systems.

No, the water was just to take out the natural shrinkage of the fabric
before putting in the artificial tautening that occurs from either the
nitrate or butyrate dope. Either dope can tauten so much that with too much
application they can actually crush the airframe. The dope grabs hold of
each fiber and pulls the spaces between the fibers closer together. This is
the tautening action achieved with using dope whether it is cotton,
polyester or glass. And yes, you can find glass fabric in the model plane
catalogs that can acheive similar results.

We would be glad to send anyone our instruction manual for free if they will
just send us their snail-mail address. I hope that I've sparked som
interest in the alternatives available to the aircraft builders.

One other thing, though. The use of epoxy or polyester resin combined with
glass again starts the deterioration clock. The glass is permanent, but the
resins are what age so quickly in the presense of UV radiation. Old
fiberglass boats look rough after a few years and will burn like gasoline.
The glass does not age and will be the big mess left after the fire since it
does not burn. Our process doesn't use any resins as one usually assumes
when glass is mentioned. The "temporary cellulose" base dope is used to
fill and tauten only. It can burn off but the glass will remain in place
with little to no loss of strength to the fabric. The late Bill Hale always
used our fabric on his acrobatic aircraft due to the glass acting as a fire
wall to the occupant. Many NASA experimental windmill and wind tunnel
blades have been covered with our glass as well.
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Del Rawlins-
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