>In winter downunder the temps in my workshop reach about 10-12 degrees C
without supplemental heat. Any advice would be appreciated<
Hi Tony
I have found 20-21 degrees centigrade to be perfect for lay-ups. Too much
hotter and they go off too quickly, particularly if you're an old fusspot
like me who seeks perfection with every lay-up! Too much less than this
and the lay-up will take a long time to go off. I found an ordinary 3kW fan
heater ideal, though an air conditioner might be better. By heating up the
air in your workshop from 10 to 20 degrees centigrade your humidity will
fall markedly. Even in the UK climate there are very few days in the
year - in fact I can't think
of any - when the humidity was outside limits.
When doing the wing leading-edge lay-ups I too went for the slow hardener.
I shudder to think what woyuld have happened if I hadn't. You must, must,
use the rubber squeeges (available from Aircraft Spruce and about 6" long)
when you do the leading edge and trailing edge lay-ups. I can't see how
you could do the jobs without them. Best of luck!
Lloyd Owens
-----Original Message-----
From: Tony Renshaw <renshaw@ozemail.com.au>
Date: 25 May 1999 12:13
Subject: Winter Layups
>Gidday,
>I am considering doing layups throughout winter using an airconditioner to
>supplement the heat and would like to request if anyone thinks this
>inadvisable due to the hydroscopic nature of the resin and cloth. I intend
>to do the flap skins and the leading edge of the wings (Classic Mk I ). I
>figure if I do it on a dry winter day with a relative humidity of less than
>60% in the workshop, the risk lies in the fact that the airconditioner will
>pass numerous airchanges over the job throughout the cure, and I will be
>using the SP Systems Slow Hardener for mixing. You Northern Hemisphere
>fellas are probably used to doing layups in winter, and may easily be able
>to allay my fears (I hope so). I havent seen a job that has absorbed a lot
>of moisture but I seem to remember it looks a bit milky when it has gone
>off. Is this correct????
>The main problem seems to be having to run the airconditioner throughout
>the entire cure 24-36 hours to ensure adaquate heat to maintain the
>chemical reaction. In winter downunder the temps in my workshop reach about
>10-12 degrees C without supplemental heat.
>Any advice would be appreciated, as I do not want to find excuses to kill
>my resurected enthusiasm.
>Reg
>Tony Renshaw
>Builder No.236
>Reg
>Tony Renshaw
>Builder No.236
>
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