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Brewster[_2_] Brewster[_2_] is offline
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Default poly for outdoor plywood signs

On 4/23/14 8:38 PM, Lew Hodgett wrote:
ps56k wrote:
tnx all -
Hadn't thought about the "marine" aspect of coating the wood.
And yeah, it's probably the edges that are allowing the water
infiltration. I'll look around for some options to coat the edges,
and the rest of the sides.

------------------------------------------------

"Mike Marlow" wrote:

Despite the recommendation for spar varnishes below, you better
investigate the spar varnish you are buying. Not all spar varnishes
are created equal and not all - or even many, stand up to uv. Do
not be fooled into thinking that since it's a marine application it
must be good. Do as you will, but just be advised...

-----------------------------------------------------
Mike is right, the last thing you want to use is a true spar varnish.

Spar varnish NEVER completely hardens since it is designed to flex
with the wooden spar when under load while sailing.

Haven't seen the signs, but if it was me, I would take some 100 grit
sandpaper and sand the raw plywood edges then coat with epoxy
from somebody like System 3, WEST systems, etc.

This will get you to System3.

http://tinyurl.com/mqutjkg

Allow about a week and then apply marine varnish such as Epifanes
available from West Marine or Jamestown Distributers which will
provide
the UV protection for the epoxy as well as the wood.


Good stuff that Epifanes!
I had a few old cans of Minwax 'spar varnish' that I used on some
outdoor wood (only lasted a few months in the Southwest sunshine).
Bought a can of the Jamestown dist. 'Epifanes' and after several years
things are still peachy.

I used the System III on some wood clappers for giant wind chimes and it
bit the dust after about three years. Stuff that I sprayed with clear
coat automotive paint is completely unphased (gawd awful expensive
nowadays though).

-Bruce


This will get you started.

http://tinyurl.com/mzrlg7j

Have fun.

Lew









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