I will be building a freestanding and open (no cabinet/doors) stand for a farmers sink. The under-mounted sink will have a small countertop area that frames it on three sides. The counter and stand will most likely be mahogany, although black walnut is also being considered. The countertop will see a lot of water, especially standing water, so any sealer/topcoat must be permanent (I don’t want to reapply every year or two) and very resistant to water stains and water damage in general. In short, waterproof.
I want to bring out the natural beauty of the wood without it looking as though it’s been encased in epoxy. That being said I realize it will require multiple coats of something, preferably with a matte or semi-gloss finish. The look and simplicity of oiled wood (pure tung etc.) is ideal but the lack of durability and permanence of oil on its own won’t work.
Any insights or recommendations regarding workflows or products welcome.
A big no to shellac, at all. It just doesn't tolerate water.
An undermount sink is a big problem. All of that exposed endgrain is just going to soak up that water.
I know it's not what you asked, but I would never have a wood top on this. If I had no choice, I would use the best marinevarnish I could find -- from a marine supply store, not a big-box store. But that's definitely going to give you the look you don't want.
I thought about making the sink level with the countertop to minimize the exposed endgrain but it's not a perfect solution.
The stand is for a friend who wants a hardwood countertop.
I'm still researching the pros and cons of varnish, poly etc. I'm sure I'll find an acceptable solution even if it's not exactly what I expected.
A self-rimming sink is a no-brainer.
True, but the sink has already been purchased and is not self-rimming.
I’d consider teak for the countertop. Separately, Osmo decking oil is worth a look as a good overall water resistant finish (have not used it though).
Teak did come up as one of the early options. Not sure why it didn't make the shortlist.
Anyone have experience with Waterlox products?
I have a lot of experience with Waterlox products. I use the Waterlox Original Transparent as my primary finish, and have used some of their other finishes occasionally. I have a cherry strip laminated ("butcher block") countertop in my kitchen that I finished with about 6 coats of Waterlox. The Original is oil based, and is a "wiping varnish" which means it has a lower percentage of solids that some heavier finishes. It has some definite advantages besides being beautiful. The first coat (at least) penetrates the wood and seals it better than a topcoat finish like polyurethane. Multiple coats add protection and beauty. It is a relatively soft finish, which makes it unlikely to crack or haze, but more likely to abrade or scratch. Unlike poly, it is repairable, in that you can gently clean it and add another coat or two without problems (as long as you haven't waxed it.) The surface finishes like poly suffer from the defect that if they do crack or are an imperfect seal, water will get into the wood and spread out, then will not be able to get back out of the narrow crack that it entered thru. Polyurethane can only be "repaired" by completely removing and starting over, as after it cures, nothing, including more coats, will stick to it. And if you don't get the re-coat timing right on poly, it can delaminate and you will be stripping it all off.
Waterlox has developed some newer finishes that I have not used. They have an 800 phone number, and I have found their tech support to be very helpful. You could call them to find out what might be the best product or combination for your situation. Good luck!
Thank you @jharveyb, very helpful information. I did contact them earlier about whether their waterbased H2OLOX is actually waterproof like the Original oil version claims.
F.Y.I. for anyone interested. I got a response from Waterlox and they say their water-based H2OLOX is every bit as waterproof and durable as the Original oil version. I hope that's true because the lower VOC is an added benefit but I've not used either product so I can't speak to the long-term accuracy of that claim.
I use water based finishes indoor and they have been impervious to water and make a harder finish than oil based, so more easy to use and don’t build up a thick film like the oil, they lack the amber tones but can be colored with dye.
Ipe is readily available 1" thick as decking... rock hard & holds up great to water.
Oh, that's nice.
It will be impossible to meet all the requirements you listed, and I would add that the finish has to endure abrasion as does a countertop. Before suggesting solutions, could you tell which requirements you would be ready to drop and which is most important to you.
The counter material will remain solid hardwood because that's what my friend wants even if other materials are easier to clean and maintain. That won't change.
So with that in mind the singlemost important finishing aspect is making it as resistant to water damage as possible. If that means putting multiple coats of a sealer and topcoat on, fine. If it will have to be touched up periodically so be it.
I'm less concerned about abrasion because the "countertop" won't see use as one in the traditional sense. It's a narrow three-sided frame around the sink. A ledge for mounting the fixtures (faucet and water filter) or putting a soap dish and scrubber. The most wear-n-tear it will see is whatever the water does to it so anything I can do to minimize that effect via a durable finish is my priority. Having looked at all the Waterlox products they just might be what I need but I'm open to any suggestions.
Waterlox for marine use is a highly diluted spar varnish, spar varnish is the most durable finish for outdoor use if enough coats are applied. A minimum of 6 coats of a good, thick spar varnish is a durable finish, with over 60% solvents in Waterlox that number of coats will only increase, if you go that route a true marine spar varnish would save time and money. It’s a soft finish however so will not have abrasion resistance and dents will cause water ingress and it will peel.
If UV exposure can be limited, Cetol is the most enduring finish, we used it extensively on teak decks and it would go 8 years with an overcoat every other year but the recipie has changed and has so much pigments now that you can barely see the wood.
The ultimate varnish is Interlux Perfection two component polyurethane. Applied over mahogany or teak, it will outlast any of the previous suggestions and have abrasion resistance . The drawback is that once weathered, and it will fail as any outdoor finish, it can’t be stripped and will require sanding back to bare wood.
In all these finishes, the thicker the finish the longer it will last outdoor, it’s really a question of having a thick barrier.
Interesting info @gulfstar.
Being an indoor fixture that gets indirect sunlight at most and is in a reasonably temperature controlled room (a bit warmer/cooler in the worst summer/winter months) I can't imagine it will be subjected to anything approaching harsh environmental conditions other than the owner leaving standing water on it.
I'll look into the products you mentioned.
For some reason I taught the piece would be outdoor, you can get away with fewer coats indoor, others have positive experience with Waterlox my suggestions were from maintaining bright work on boats.
Try a thinned epoxy. It will soak into the wood and set hard giving a water resistant primer to whatever finish you put on top. I did it with a vanity where the sink sits on top. 3 coats of varnish on top and water will never get in, well not in the 5 years its been used so far
According to this 2009 FWW article on testing outdoor finishes, several coats of epoxy sealer and then several coats of spar varnish, faired the best.
I remember that article, the main reason epoxy primer is not widely used on boats is that one day, between 5 and 10 years it will have to be removed and re-done and epoxy will not comme off with a chemical stripper so it will be a big, difficult job to get to the bare wood evenly. Indoor it will last forever.