In article <3A97DF2F.35C89466@ameritech.net>,
fillinger@ameritech.net (Fred Fillinger) wrote:
> Couple things, Steve. I thought that post-curing is
largely
> ineffective unless done within a couple weeks of a
room-temperature
> cure. Thus it applies only to the few such surfaces
required of
> current XS kits. Has the Europa manual guidance in this
regard
> changed?
Fred
Post curing has two functions I believe; one as you say will
improve the strength of the lay-up. This effect reduces with
the delay in carrying it out. I asked the factory when post
curing had been done on the classic wing used for the load
test and the answer was that it was built by a contractor
and so had no idea, but I came away with the impression that
any post cure strength increase would be a bonus and is not
called for in the design. Perhaps Andy Draper could confirm
this.
The other one is to ensure that the layup will be stable up
to the curing temperature. In other words your wing wont
start to droop when you leave it out in the sun. Not a
problem here. :-((
The third of two reasons is to burn off any compounds which
might later affect the finish. The inside of my polystyrene
cage turned from white to pale brown by the end of the cure.
Paul
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