Note: Next Monday’s post will be an update shedding light on the results here and adding further important information.
As a maker of custom furniture and cabinetry, I use a variety of finishes. Some pieces need minimal protection – perhaps sealed with shellac and a coat of buffed wax, or finished with a blend of boiled linseed oil and polyurethane. Sometimes I brush oil-based poly onto horizontal surfaces that are going to get a lot of household wear; sometimes I use Osmo because an ultra-low sheen is what my client desires. Other jobs call for conversion varnish or lacquer; although I’ve sprayed lacquers when working at other businesses in the past, I don’t spray in my shop, so I sub such work out.
I have a basic repertoire of finishes to choose from, depending on a client’s aesthetic preferences and way of living. (Some people treat their home as carefully as if it were a museum. Others are like bulls in a china shop, leaning back in chairs and flinging spaghetti sauce in the kitchen.) I add new finishes occasionally, subjecting each to the following test (and sometimes additional tests) before agreeing to use it. On every job I discuss finish options in detail, explaining pros and cons and giving my recommendation based on whatever considerations are important to the client. Then I let him, her, or them make an informed decision.
Fortunately, most of the people I work for are not entitled idiots ready to blame me for their own recklessness, but intelligent humans willing to use their brains and take responsibility for how they interact with their furniture. I am not in the business of promising bomb-proof products. (If you are, good luck with that.) Most of my clients are happy to use heat- and moisture-impervious coasters. Some are especially concerned about scratches, others about ease of repair, the degree of ambering imparted by a finish, and so on. The one consideration I’ve found universal* is resistance to stains from drips, spills, and splatters. No matter how careful you are (and how firmly you advise your guests to put their glasses or cups on coasters), accidental contact with potentially damaging liquids is inevitable unless you keep your furniture wrapped in protective plastic.
This post is intended to provide the kind of information that I find generally useful in my work as a designer-maker of furniture, whether built-in or freestanding. You should perform your own experiments using the specific substances likely to be used around your work. (For example, I only tested comestibles here, not pharmaceutical or cleaning products.)
The four finishing products here are readily available and easy to use. None requires spraying or added a catalyst.
Note: I have described the process I used to apply each of the finishes, but your results may still diverge from mine, depending on other variables (among them the vinegar content of your hot sauce).
To ensure a basic level of consistency I made four blanks from a single piece of curly maple, which I resawed, then cut in half.
Testing, testing …
I sanded each block to 220 grit and removed the dust. I applied each finish as described below, then left each for 24 hours before performing the experiment. I put the same substances on each sample and left them in place for one hour, then wiped them off with a damp rag, dried them with a paper towel, and observed the results.
I applied two coats of Osmo Polyx Oil in Natural, which is recommended for use on pale species to retain the coolest tone. I applied the finish with a shop cloth, wiping away the excess and smoothing between coats with a white non-abrasive pad. Then I applied a further coat, this time of Osmo Polyx Oil 3054 using the same method.
Performance: The red wine and hot sauce left marks – a barely noticeable mark in the former case but a bad stain in the latter. There was no discernible effect left on the finish by the other substances.
Cabot Water-Based Poly
I had the lowest expectations for this one, thanks to my experience with other water-based polyurethanes. I started using water-based finishes around 1990, happy about the promise of durability without petroleum solvents, but in too many cases the performance failed to match the promises. I wanted to try a new (to me) water-based finish for this test.
I applied three good coats with a foam brush, scuffing between with a non-abrasive pad.
Performance: With the other water-based polys I’ve used in the past, I’ve found that butter and oil got through the finish and left a mark. This Cabot poly was impervious to oils. The only stain came from the hot sauce.
Minwax Oil-Based Fast-Drying Poly (Satin)
This has been my go-to finish for table tops; other than conversion varnish, I’ve found it to be the most durable. Polyurethane gets a bad rap in part because so many people apply it thickly or with the wrong kind of brush. I’ve found that three thin coats applied with a natural bristle brush, scuffed with 320 grit between coats, will produce a nice satin sheen — granted, it’s not as low-luster as Osmo, and oil-based poly is more trouble to work with because it requires several hours in a dust-free environment.
Performance: This one showed no discernible marks. If I try hard, I can persuade myself that I see a spot from the hot sauce, but I think I’m imagining it.
Minwax Helmsman Spar Varnish
I applied three coats – the first two with a foam brush, the third a heavier coat with a natural bristle brush. I scuffed the finish between coats with 320 grit and removed dust.
Performance: The only substance to leave a mark was the hot sauce. The mark is barely noticeable, but … well … it’s there.
Each of these finishes has its uses, depending on the durability, sheen, and degree of ambering you desire. My favorite for appearance is Osmo, but the winner for durability is the oil-based poly.
Thanks to the vinegar in the ketchup and hot sauce, our kitchen now smells like a chip shop.
From now on I’m keeping the hot sauce off the table.
For what it’s worth, I give every client a detailed set of care instructions on completion of the job. These instructions always advise wiping up any spills or splatters immediately and drying the furniture with a soft cloth, as well as using heat- and moisture-impervious coasters or dishes beneath glasses, serving ware, or potted plants.
*Full disclosure: I do have one client who relishes the prospect of her table developing a patina of stains and scratches that will record its history.