Re: Diluting Epoxy (for a secondary coat)

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Original poster: "Mark Broker by way of Terry Fritz <twftesla-at-uswest-dot-net>" <broker-at-uwplatt.edu>


>
>
> Hello,
>     For my new secondary, I was wondering if I could just mix 2-part liquid
> epoxy and use that as the one and only coating.  The only problem that I can
> see would be that the epoxy might not be fluid enough.  Should I use epoxy,
> or just use many coats of varathane?  How might I dilute the epoxy and make
> it flow better, but not affect the drying times?  Thanks for all the help to
> come.
> 
>     Bart Mc.

Bart,

After having built a pair of cedar strip canoes, I feel I can give you some
advise regarding epoxy.  If you get a good, high quality epoxy, you won't need
to dilute it, as it'll be about as viscous as warm honey (think 80-weight
oil).  An epoxy thinner can be used, but since it's only a little thicker than
varnish, I wouldn't recommend it.

Some things to note about epoxy:

The resin-hardner chemical reaction is exothermic in nature.  The warmer it is,
the faster it sets.  Under "autumn" conditions (about 65F, 75%humidity), I
found that the epoxy got really sticky and tacky (and generally unworkable)
after about 20 minutes.  In an hour, it had set to the point where thick parts
could still be dented with a fingernail.  About 24 hours later, the epoxy had
hardened.

Epoxy breaks down under UV light.  You will need to apply a coat of varnish,
anyway (spray on should satin gives a nice finish....)

Mark B