----- Original Message -----
From: Fred Fillinger <fillinger@ameritech.net>
Subject: Re: Fill and Bake, or Bake and Fill?
> Following a test I did, I need to add important info re "foam may not
> stand that" below. The blue foam will distort very badly above 170F
> (77C), and seems a function of uneven temps around the component.
> Even heating in a large, homemade autoclave is hard to achieve w/o
> fancy methods of air circulation. That suggests bake temp well below
> 150F (65C), which reduces the effect of the postcure (increasing bake
> time does nothing they say).
>
> I'm starting to think that low-temp postcure does little, but if not
> done, exact mix ratio, low humidity, fresh epoxy and all that become
> more important. Neither in Rutan/Yaeger's book on the Voyager, nor in
> the TV documentary, is postcure mentioned (would have some big
> oven!). Great book BTW.
>
> Regards,
> Fred F., A063
Fred:
Well mebbe. I sent two samplesa of my Aeropoxy construction to
Stuttgart for formal testing. The test showed that the epoxy gained 8C
degrees in Tg from room temp to baking 10 hours at 50degC (with suitable up-
and down-ramping).
I don't know if this is signifigant in practical terms, but it
does provide some protection against softerning - we get up to 38deg C in
summer peaks here and I have no idea what my baby will be called to
withstand
Happy Landings
Ferg A064
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