Epoxy is really crap for homebuilding

"Sliker" wrote in message
...
Lately I've had to use the stuff to work with some pre-made parts that
were made from epoxy. Aeropoxy. Stinky!
Epoxy is more viscose, so it doesn't wet out the cloth as well. It is
more toxic, especially some of the older formulas. And smells
horrible. And why did so many homebuilders get stuck using that crap?
Rutan. Those hot wired, foam core wings and other parts to be exact.
The type of foam that can be hotwired, dissolves when in contact with
vinyl ester or polyester resin. So they had to use epoxy. What they
should have done is figured out another way to cut the foam cores with
something like a wire saw, and used polyurethane foam and vinyl ester
resin. Plus, epoxy is expensive, and much more flameable. So it's use
in aircraft has so many negatives, it should never have been used.
Rutan really put one on us with the epoxy legacy.

There are really a couple of issues here.

First, I really don't like the hot wire method of forming foam because of
the fumes that result; but I no longer recall which of the current materials
were available in those days. However, I do seem to recall that the
so-called "Safety-Poxy" which Burt recommended was hailed, at the time, as
something of a breakthrough in both safety and ease of use in a relatively
wide range of working environments.

Second, despite some later crumbling about the dimensioning of interior
bulkheads, Burt's idea was that the Vari-Eze should be extremely easy and
quick to construct. IIRC, two people were supposed to be able to do it in
less than a month--or about 300 man hours total time. When the results
drastically deviated from that concept, Burt went on tour and showed how it
was done. I had the privelege of attenting one of his "hands-on" seminar
demonstrations in Fort Lauderdale at the time--and it was abundantly clear
that, if you learned to work the way he worked, the problems were minimized.

Peter

P.S.: I do agree that there are far better materials available today, and
also better cutting methods; but Burt my point is simply that Burt is not
culpable!