View Single Post
  #3   Report Post  
Bob S.
 
Posts: n/a
Default Varnish Finish Failure

Joe,

There was a recent article by Michael Flexner (sp) in one of the mags that
answered this question. Simply the answer is ...no. The UV will continue
to cause the wood to discolor. You can stain (oil based - penetrates
better), or paint but any clear topcoat is going to allow the UV through.

Bob S.

"Joe Nation" wrote in message
...
I built a park bench out of white oak. I wanted to prevent the oak from
changing color due to weathering and finished it with a water based marine
grade UV stabalized varnish. The bench has been exposed to direct

sunlight
and rain for about 4 months and it is apparent that the varnish is not
preventing moisture from getting under the finish. The oak lumber in a lot
of places is begining to change colors. The color change is greatest in

the
part of the white oak lumber that has small pores exposed to the surface.
The varnish remains attached to the entire surface and shows no signs of
pealing. What can I do to this piece to preserve its original nonweathered
oak color. Is there a marine spar varnish that will protect the oak and
prevent a change in its color? Can this bench be recoated with a spar
varnish that will stop any future color changes to the wood?

I googled on spar varnish and did not find much help with this problem.

Any
help you can give me would be appreciated.
--
Joe Nation Assistant Superintendent - Retired
Ballinger, Texas 76821