Gidday,
For fear of entering where I shouldn't tread, firstly the residue is called
"amine blush". It is supposedly water soluble, so later on it can be washed
off. I however have my own theory. Have you ever noticed the odour when you
remove peel ply? What does it smell like to you? Well, to me it smells of my SP
Systems Ampreg 20 hardener, a perfect match. This is the same odour you will
get when you start to sand a raw edge too, if your silly enough to do it
without your respirator on. I reckon the hardener is a curing, and yet strength
compromising ingredient. If you heat up your cured components, or in fact the
room as you build up the heat for a hot initial cure, the smell is hardener.
So, since strength is increased with postcure and you smell hardener, well the
process is "boiling it off, or out of your work". This is very much a laymans
determination, but I'll bet a VB I'm right! This is part of the reason why you
shouldn't handle the layups after cure, although the experts will tell you it
is to minimise oils from your skin compromising the bonding abilities of future
coatings, but I am sure this handling is contributory to the allergic
reactions certain people have. The hardener is the evil here. If you are
starting to get any symptoms of allergy, well I would be putting on my cotton
gloves as a matter of course when in the plane factory.
Reg
Tony Renshaw
Sydney Australia
>
>Hi! Gary.
>For my experiences you need to not only control the heat high but also the
>humidity needs to be as low as possible for the whole of the curing period.
>The moisture combines with the surface and produces the "glue like"
>substance that Richard thinks is uncured resin.(there is a name for it but
>it escapes me) My experience of the Expandcell on the tail planes was
>sufficient for me to change over to Polyfibre. A by far superior substance
>to apply, cure and sand back. Their Smooth prime is then next applied by
>roller and is also extremely easy to "cut back" and "rag" pin holes away.
>(but both are expensive!)
>Also watch out that you don't loose the wing profiles, but I guess you have
>an XS with the "Aero-Fix" wing skins so perhaps not to worry on that score!
>regards
>Bob Harrison G-PTAG
>
>-----Original Message-----
>From: owner-europa-list-server@matronics.com
>[mailto:owner-europa-list-server@matronics.com]On Behalf Of Garry
>Copeland
>To: europa list
>Subject: Europa-List: Control surfaces filling
>
>
><garrett.copeland@btinternet.com>
>
>Folks,
>I am about to start filling my control surfaces. Since space is limited I
>plan on filling all the surfaces, then erecting some dust contol measures
>and sanding them all.
>Is there an optimum time between filling and sanding back? I expect it will
>be a few weeks between filling the first surface and starting to sand it.
>I plan on using the Expancel that came with the kit.
>
>Thanks.
>
>Garry
>
>
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