Seal end grain for outdoor bench

[Scott Goldthwaite]

I'm replacing the seat planks of an outdoor bench with white oak. The planks will be bolted to a metal frame on each end, there's no joinery. I'd like to seal the end grain to slow down water penetrating into the wood. I was thinking of using a penetrating epoxy like Smith CPES or Total Boat. I've used Smith's before, but not Total Boat. I think Smith's is lower viscosity. I could also use West Epoxy (which I have) and add some solvent. I could put West epoxy on the end without thinning. It wouldn't penetrate as much, but would probably seal pretty well. I will not be finishing the wood. I'm interested in hearing peoples thought and suggestions on this.

Thanks,
Scott

[Jeff Roltgen]

Scott,
Seems a good idea. Only experience I've had close to this is some Ipe outdoor benches. Was concerned about end grain moisture wicking where leg meets floor, and used either thinned epoxy or CPES. While I think that helped (15 years ago), I also epoxied a small "shoe" under each leg. Still have my tester bench outside, and though the epifanes is in desperate need of work, the legs have remained very clean/no cracks at ground level. Not exactly what your describing, but similar concept. Thin your epoxy for first coat (30%), slightly thinner on 2nd (15-20%), full strength 3rd. Should be able to see a decent film building at that point. I believe the Smiths system is more dependent on a paint or at least varnish coat for UV protection, so the West Systems epoxy may be better suited in this case.

Good luck!
jeff

[Maurice Mcmurry]

If you are not finishing the rest of the wood I think the epoxy coated ends could create a water proof cap that might actually retain moisture. I have used "Old Down East Deck Finnish" for exterior wood in a natural Finnish. Consider soaking the ends in this concoction and using it on all of the wood as well. I am looking for the recipe now it is from Jamestown Distributors.

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[Scott Goldthwaite]

Thanks. I do have some UV resistant West epoxy, might as well use that.

[Stan Calow]

Note the parts that you coat with epoxy may end up a different color as the bench fades. I used epoxy to glue up a all-wood outdoor bench, and the places where epoxy squeezed out of joints that I didnt catch remained an un-faded yellowish color as the rest of the (oiled) oak turned gray.

[Scott Goldthwaite]

Note the parts that you coat with epoxy may end up a different color as the bench fades. I used epoxy to glue up a all-wood outdoor bench, and the places where epoxy squeezed out of joints that I didn't catch remained an un-faded yellowish color as the rest of the (oiled) oak turned gray.

Thanks Stan. I'm doing end grain only. I'll keep any epoxy off the face grain. So, I should be okay.

[Holmes Anderson]

Scott,

Just use Anchorseal. It is designed to seal end grain on unfinished wood.

Why not epoxy? Is there really a UV-resistant epoxy? I have built multiple stitch-and-glue boats with epoxy and also used it for repairs to fiberglass boats, but I have never seen any UV-resistant epoxy. Even if it existed, it would look much different from the unfinished parts of the bench. I just looked at the West System website and didn't find a UV-resist resin, but this is a quote from their advice on repairs to wooden boats:

Sunlight poses a threat to the structure and finish of all composite boats. It attacks in
two ways: heat and ultraviolet (UV) rays. Any epoxy finishes without protective coatings
are vulnerable to rapid ultraviolet degradation. WEST SYSTEM Epoxy, including the 207
Special Clear Hardener™, is not intended to be used as a final finish. Therefore, you
should cover bare epoxy that will be exposed to direct sunlight as soon as possible with
an opaque paint or a clear coating (varnish). If the surface is to be painted, add pigment
to the last two coats of epoxy to protect the surface. Surfaces that receive indirect UV
exposure, such as those below decks, will last much longer without a protective coating
than directly exposed surfaces.

[Scott Goldthwaite]

Thanks for the info Holmes. West must have discontinued their UV epoxy. I have a can I purchased a long time ago. I hadn't thought about painting the end grain. Since you can't really see the endgrain anyway, I may go ahead and do that.