Will,
I placed all my parts in my garage attic where the temps we're hovering
around 140 to 150F. Couldn't get the wings up there so I laid them on a
padded surface in my driveway in the direct sun after I applied the PPG
high build primer. It was dark gray and the temps we're higher than
they would have been after the white final coat so I figured they would
get all the cure they need. After the all day sun I blocked sanded them
down again before final prime and paint. This was my second summer on
them and they're still looking good. I did the same thing for the
fuselage. Hope this helps.
Jeff R.
A258 - N128LJ / Gold Rush 86 hours flying and climbing slowly.
PS. Anyone out there in USA know of a good hypnotist that could
convince my wife's subconscious mind she loves to fly? ;o)
On Sep 11, 2007, at 10:39 AM, Rob Housman wrote:
>
> Short answer: NO.
>
> I have no specific information about the Aeropoxy material (there is
> nothing
> about this on the Aeropoxy web site) but in general for epoxies (and
> other
> thermosetting polymers)the cure temperature affects the glass
> transition
> temperature, T sub g. While the polymerization reaction generally
> behaves
> in the expected fashion, i. e., longer soak at lower temperature being
> somewhat equivalent to a shorter soak at a higher temperature, the
> critical
> factor here is to have the cure temperature high enough to cure the
> epoxy to
> a high T sub g.
>
> The glass transition temperature is actually not a specific
> temperature (the
> melting point of ice for example) but rather a range of temperature
> through
> which the material transitions from being hard and glassy to being
> soft and
> rubbery. The higher the cure temperature the higher the glass
> transition
> temperature, and that translates directly to a stronger airframe when
> ambient temperature is high.
>
> Jos Okhuijsen is correct on both points - cure all parts with builder
> applied epoxy and cure at a temperature higher than you expect to
> encounter.
>
>
> Best regards,
>
> Rob Housman
> Irvine, California
> Europa XS Tri-Gear
> S/N A070
> Airframe complete
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] On Behalf Of William
> Daniell
> Sent: Tuesday, September 11, 2007 6:25 AM
> To: europa-list@matronics.com
> Subject: Europa-List: Post cure
>
> <wdaniell@etb.net.co>
>
> As I understand it the blue foam bits need post cure.
>
> I believe this is 40C for a period of 24 hours.
>
> Can this be done at a lower heat for longer time to get the same
> results?
>
> Will
>
> 17:43
>
>
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