Message-ID: <36A6C8FF.1F17111@tin.it>
Date: Thu, 21 Jan 1999 07:28:15 +0100
From: John F: Herminghaus <catignano@tin.it>
Reply-To: catignano@tin.it
To: Lancairlist <lancair.list@olsusa.com>
Subject: Jeffco epoxy working time
Mime-Version: 1.0

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There is apparently no way to extend the pot life
of the Jeffco epoxy.  Just wait until you have
temperatures in the nineties.  It hardens while
you're still mixing.

Lancair is testing a new combination from Jeffco
with a longer pot life.  Carsteb Sundren promised
that it would be released by last October, but
then pushed the date back to sometime this year
with no explanation.  

The only other solution is to use another epoxy
system.  In my case a German product which has a
pot life of 90 minutes - in other words, long
enough to the flox buildups on the main spars
etc.  The mixing ratio is identical to Jeffco i.e.
1/28 by volume, 1/25 by weight.  It is not
approved by Lancair but has been certified by the
German equivalent of the FAA, which is good enough
for me.  I know of at least one other builder of a
IV in Germany who is using it as well as Lancair
Espana.  I must note that it requires heat
treatment at 60°C for 10 hours.  I have solved
that problem by becoming friendly with the local
body shop which just happens to have a painting
booth which meets the requirements.

It does, of course, take longer to cure. 
Depending on the job to done, sometimes I use one,
sometimes the other.  That is when the
temperatures are normal.

If you would like more information, let me know.

John Herminghaus
I-VVVV