Replies

1. 
   | Aug 26, 2009 02:58pm | #1

   Hello Phil,

   If you must have a finish on wood that is going to be exposed to the elements, you must plan on maintaining it with frequent light sanding and reapplication of the finish.

   Bob, Tupper Lake, NY

2. 
   SteveSchoene | Aug 26, 2009 03:02pm | #2

   It's always tough to get any clear finish to perform in sunlight, particularly as far south as Houston.  First, I assume this is white oak, red oak isn't up to the task. 

   My best recommendation is to strip off the finish and then let  white oak weather to it's natural grey color.  Scrub it down every season and live with it that way for many years.  If you don't want grey, make Sunbrella fabric covers for them to be used whenever not actually setting on them.  Or build a roof for the patio to provide shade.

   But, if you do want a clear finish, be aware that you are commiting to sustantial and continuing maintenance. 

   Spar varnish is the right finish, but not just any spar varnish.  Only the best, high end marine spar varnish will perform well.  By this I mean the top traditional varnish products from Interlux (Schooner), Pettit (Captain's), or Epifanes (Clear Gloss).   (A recent FWW article tested Epifanes against other lesser products.)

   This good marine spar needs to be applied according to manufacturers instructions which all call for at least 5 to 7 coats initially, scuff sanding between coats.  (This is a drawback for spar varnish in that the high gloss fill finish isn't always the most comfortable to sit on.)  The thickness of the coat is important. 

   Then, you need to be committed to scuff sanding and adding a refresher coat every year or when ever the finish starts to dull.  Eventually, the finish will start to deteriorate from the inside, developing "yellow" patches signalling that it is lifting from the wood.  This means that soon you will have to strip it all off and start anew.  Also, be quick to touch up any dings--once the film is broken, water enters and can quickly reak havoc.   

   One other point--make sure the ground contact surfaces have been well sealed with epoxy--applied to the point of full saturation. 

3. 
   HowardAcheson | Aug 26, 2009 06:04pm | #3

   >> Spar varnish is the right finish, but not just any spar varnish. Only the best, high end marine spar varnish will perform well. By this I mean the top traditional varnish products from Interlux (Schooner), Pettit (Captain's), or Epifanes (Clear Gloss). (A recent FWW article tested Epifanes against other lesser products.)

   Continuing Steve's thought, you want to avoid any consumer brand, big box "spar varnish". These all are poly varnishes. Polyurethane is rapidly attacked by the UV in sunlight and will quickly fail.

   Long term tests of exterior finishes has found that there is not clear finish that will last much more than a year in high UV exterior locations. And, the more opaque the finish, the longer it will last.

   Howie.........
1. 
   KiddervilleAcres | Aug 28, 2009 05:22am | #4

   Howie,

   I'm sure you know this but I understand (from Steve?) that Cabot is selling McCloskey's varnishes, or something like that.  I believe the cans are marked with certain series' of numbers.

   Regards,Bob @ Kidderville Acres

   A Woodworkers mind should be the sharpest tool in the shop!

1. 
   SteveSchoene | Aug 28, 2009 05:34am | #5

   Yes, but neither the products still marketed as McCloskey (I think the Man-O-War Spar Varnish fits that bill nor the products now marketed as Cabot brands(the 8000 series of Cabot varnishes that used to be McCloskey Heirloom) are suitable for outdoor furniture. 

1. 
   KiddervilleAcres | Aug 28, 2009 03:59pm | #6

   Steve,

   Thanks, I had some confusion as to the details.  I understand about the 8000 series numbers but isn't there a 4000 series also?

   Regards,Bob @ Kidderville Acres

   A Woodworkers mind should be the sharpest tool in the shop!

1. 
   HowardAcheson | Aug 28, 2009 06:31pm | #7

   It gets a little confusing and I may not have this exactly correct but, Valspar owns the Cabot and McCloskey brand names. In addition to the Valspar own brand name, Valspar controls and markets Cabot Spar Varnish (non-poly as far as I know) and the Mc Closkey Man-O-War Spar Varnish (still non-poly).However, neither of these products are the equal of the true marine exterior finishes identified above in my opinion. They are certainly better than other big box "marine spar varnishes polyurethane varnishes.Zinsser has recently begun marketing a non-poly spar varnish. But I have no personal knowledge of it's performance. It should out-perform any polyurethane spar varnish when used in a high UV environment.Howie.........

4. 
   whitedogstr8leg | Aug 28, 2009 06:37pm | #8

    Go to the paint store and ask for Paint Base.   It's the base that the store adds pigment to to make the colours one needs.  Without the pigments, the base dries clear.  Maybe Howie can tell  you the exact flavour of base (SW#5, I think) that will work.

   " Although I have the right to remain stupid, I try not to abuse that right"
5. 
   paulbny | Aug 29, 2009 05:42am | #9

   Phil

   Take a look at this thread.

    

   http://forums.taunton.com/fw-knots/messages?msg=46447.1

    

    

   Often in error but NEVER in doubt! 

1. 
   davcefai | Aug 30, 2009 09:08am | #10

   When I used to race sailing dinghies the boat apearance was deemed very important in order to psych out the competition.Typically a boat was used all day Saturday and Sunday (5 races) and probably 5 hours during the week for training and/or just cruising with the g/f. The boat was rinsed off after use and covered with a tarp.Despite all this it needed a full sanding and revarnishing once a year and a quick touch up just before summer.So essentially outdoor wood which is going to be treated less lovingly than this doesn't have a chance!