Also this one. Graham
I just recieved a copy of the MSDS for the curing agents for the MGS
epoxy systems. As I suspected the curing agents are classified as
"Corrosive". For shipping purposes, the materials fall under Packaging
Group II. Packaging Group I is the most corrosive, and PG III is the
least. I would treat this product carefully and keep it off your skin.
The only performance properties reported on the product technical data
sheets is the Glass Transition temperature vs. mix ratio - AFTER POST
CURING. - only 72-78C is obtainable depending on the resin / curing
agent combination.
Here is an excerpt from the data sheet for both resins and curing agent
systems -
" Laminating resin system approved by the German Federal Aviation
Authority with different pot lives for processing of glass, carbon and
aramide fibres, featuring high static and dynamic loadabillity.
After heat treatment at 50-55C, (for 15 hours minimum) the system meets
the standards for gliders and motor gliders (operational temperatures
-60C until +54C). Heat treatment at higher temperatures only reduces
the necessary heat treatment period; however, a considerable rise of the
glass transition temperature point will not be obtained.
If high heat resistance or aircraft approval are not necessary, the
system can also be used without heat treatment. However, the indicated
properties will only be obtained after heat treatment at temperatures
over 50C."
What this says is.... you better post cure this stuff or don't even
think about using it in your aircraft. I have reviewed the chemical
components in the curing agent listed on the MSDS and what they say in
the above excerpt is appropriate. These compounds do not cure well at
room temperature alone. This is not uncommon for many curing agents.
But some are better than others.
IF you have a sail plane or motor glider that was originally built with
this product, it is required that it be repaired with these products -
And, I am quite certain the repair manuals for these aircraft specify
that the repairs be heat treated (aka, POST CURED) in order to be
compliant with the GFAA and FAA's reciprocity regulations. Because
German Certified aircraft are growing in number in the United States,
Wicks Aircraft (the U.S. Supplier) is doing the owners of these
aircraft a great deed by imported the required repair resin for them.
Considering how expensive these resins are, the fact they have specific
post curing requirements and the fact they have not been tested or
approved by the designers of the various composite kitplanes we are
building, I would not consider using these resins.
Gary Hunter
Shell Chemical Co.
Epoxy Resins & Curing Agent
Technical Service Representative
EAA Technical Counselor
Vari-Eze - N235GH
gahunter@shellus.com
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From: Vernon Asper[SMTP:vasper@seahorse.ims.usm.edu]
Has anyone tried the new German Epoxy that Wicks is now pushing as a
replacement for Safe-T/EZ Poxy? I bought a kit at Sun 'n Fun.
I'd be interested in hearing others' impressions as well; sure seems
like a good product.
Vernon Asper
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