Marine Spar Varnish...inside and out?

[DMcCam]

Hi Guys, What's the general consensus about spraying several coats of marine spar varnish over all the exposed wood surfaces both inside and out? I want my TD to be natural birch with just the varnish protecting it on the inside and thought, why not do the same everywhere then add the aluminum. Is this a good idea? Is CEPS better?

Thanks,

Dave

[CliffinGA]

Dave I've been interested in this too especially after seeing Johnny do his this way before putting his aluminum on. I found this article that explains more about marine spar varnish that makes me rethink that whole idea.
http://hardwoodlumberandmore.com/Articles/ArticleViewPage/tabid/75/ArticleId/1/Marine-Varnish.aspx

Its an interesting read and I hope it helps you.

Cliff

[Dusty82]

I use marine spar urethane for interior projects, cabinets, stained trim - basically anything that needs a durable transparent finish. I knew it didn't have any real "waterproofing" advantages over regular urethanes or varnishes, but I was surprised by it's apparent lack of UV protection. I'll admit I can only speak anecdotally, but I've never had a problem with it flaking off after a season or two as described in the article - then again, I've never used it for a project that's going to be subjected to the constant UV bombardment a teardrop or a boat will be subjected to. I usually paint or use just an oil stain on outdoor projects.

Thanks for that link! Lots of food for thought there...

[aggie79]

Hi Dave,

I'm not going to be much help, but either would work. I would also consider polyurethane too.

No wanting to start up the whole CPES discussion, but I know it is used by some cabinet maufacturers as a sealer. You would still probably need to use some other material as a final finish. I used CPES on the exterior of my teardrop. From experience, if you use CPES, I would give it plenty of time to out-gas prior to installing the finish coat and I would probably use an oil-based finish coat instead of water-based in case any of the CPES solvents have not dissipated.

Take care,
Tom

[nevadatear]

Dave, we used spar varnish over the epoxy on the outside, but poly on the inside. Basically for us a cost thing. Didn't really need the extra waterproofing on the inside, so went with the poly (easier to work with too). Exciting to think you are thinking about finishes! It is coming a long.

[DMcCam]

Wow, great info guys. Of course you can all see right through my little ruse, I'm looking for an overall solution. Spray the whole thing using several coats of something, let it dry and add the aluminum...done. Sounds like here in the high desert spar varnish would work pretty well but on the interior I'd like a real hard durable coating. Poly would work for sure. I'll ask my brother this weekend too.

One of the reasons I'm looking into varnishes instead of CPES, is that I've not been able to find a source for it anywhere even close to Reno. It sounds like pretty nasty stuff.

Warmest wishes,

Dave

[Senior Ninja]

I brushed three coats of varnish over all the wood, inside and out, even the bottom of the floor. My plywood turned out to be Birch. I just couldn't justify painting Birch. It is beautiful IMHO.
Steve