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Skill Builder: What Wood Finishes Are The Most Eco Friendly?

You build tables from reclaimed beams, using solar-charged tools by daylight. Heck, you even deliver via rickshaw! But what finish can you use that’s as eco-woke as you?

Low-VOC finishes I use in my shop.
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Most finishes, even the “green” ones, contain VOCs, or volatile organic compounds, which they emit as fumes or gases. Many VOCs are known to be bad for the atmosphere and for your personal health. An easy VOC test: If it smells bad, it is bad. Never mind the short-term side effects like headaches and nausea, VOCs have been linked to liver, kidney, and nervous system damage as well as an increase in smog and tropospheric ozone. (It’s bad. You can look it up.) So our goal is to find a finish with little to no VOCs that still gets the job done.

Traditional finishes like shellacs, urethanes, and varnishes are made with alcohol and oils that are rich in VOCs, but there are safe and effective alternatives with lower VOC footprints. The more we learn about the negative effects of VOCs, the more we realize we need to find solutions. Many U.S. states are cracking down with stricter regulations, and savvy manufacturers are staying competitive by stepping up their Earth-friendly game. Here are a few of my favorite top coats from firsthand experience.

Water-Based Polyurethanes

Cleaner, water-based polyurethanes have been around for a while but are becoming better and more popular. “Water poly” has a very low VOC count, can be brushed or sprayed, and cleans up easily with water. Several companies make these finishes in a variety of mixtures and thicknesses and they usually have little to no effect on the color of the wood. With patience and wet sanding in between coats, a thick, high-gloss shine that rivals the bad stuff can be achieved.

Emtech by Target Coatings: They make a water-based version of all your traditional favs.

Target Coatings makes a fantastic line of water-based finishes including a conversion varnish that features a hybrid blend of oils and resins. I have not yet tried it but I have used their waterborne polyurethane and it performed great.

In a pinch, Varathane water polyurethane is usually available at the box stores and works fine. They make a “triple thick” formula that works well on very rustic wood, filling in some of the cracks and voids. It creates a plastic-like layer that you may or may not like, so try it out on a cut-off first.

TotalBoat tries to save on packaging and waste with its bagged instead of canned Halcyon finishes.

TotalBoat also makes a water-based product called Halcyon that comes in clear or amber tinted formulas. It’s a little thicker than most but slightly thinner than the triple thick Varathane. I find it to be “just right” for my projects. I am fond of the warm amber wood coloring, and I prefer their foil packages with resealable caps over old-fashioned cans, which reduces packaging and product waste. (Disclosure: I have a sponsorship agreement with TotalBoat so I am admittedly biased.)

Epoxy Resins

Spend any time looking at woodworking videos online and you’ll see that epoxy is all the rage. It can create clear, glass-like coverings or be used with pigments to create startling, colorful effects. But is it doing more harm than good?

Water-based polyurethane brushed on and wet sanded between every third coat.

Epoxy resin is typically made of two separate chemical mixtures that, when combined, harden into a clear, ultra durable surface. There are certainly many types and brands out there in varying degrees of harmfulness, but more and more attention is being paid to their effects. Once cured, most epoxies are safe and many are low VOC and made with Earth-friendly ingredients.

Guitars HVLP sprayed with about 10 thin coats of TotalBoat amber-tinted Halcyon.

If you need a finish that is super thick and durable, I would choose epoxy over spar urethane or other old-fashioned varnishes. Read the labels to get the right epoxy for your project; use and clean it up properly and you can still feel OK about your footprint in the morning. There are companies like EcoPoxy, who make eco-friendly epoxies that a trustworthy peer tells me work well. ArtResin also makes a “green” epoxy with rave reviews.

Working with reclaimed wood, I sometimes find myself using epoxy to fill voids and secure highly damaged parts of the wood. TotalBoat makes many epoxies including a thin penetrating epoxy designed for this type of work that is low VOC and environmentally friendly.

Oils (the Good Kind)

Water poly is more of a top-coat that wraps a protective layer around the work. If you want something that penetrates the wood pores, you are looking for oil. Mineral oil and linseed oil are old-fashioned, tried-and-true wood finishes that are inexpensive, readily available, and not horrible for the world. Linseed oil is made from flax (it’s also known as flaxseed oil) and, by itself, makes a fine finish that leaves wood darker, richer, and feeling natural. Sometimes it is mixed with turpentine and other less pleasant things, but this is not necessary. Read on for my favorite recipe.

I found this cool, halffilled bottle of mineral oil at a junk shop years ago and now refill it often.

Mineral oil is made from petroleum but highly cleaned and distilled. I buy it in my local drug store as it is also used as a laxative and relatively benign. I understand why one might not want to use anything petroleum-based but it is certainly better than many of the alternatives and is food-safe right out of the bottle. You can literally drink it!

Local beeswax mixed with mineral oil; good enough to eat!

A few years ago I melted some wax from a local beekeeper and made my own polishes. One was beeswax and linseed, the other mineral oil and wax, mixed about 50/50. I love using these and the wax adds to the protection. Telling clients you use a homemade finish is also a plus.

Rubio Monocoat: This little soup-size can costs as much as a gallon of other finishes, but a little goes an incredibly long way.

There are many other kinds of plant-based oil products out there like Walrus Oil, Odie’s Oil and SafeCoat, to name a few, but I have not used them so I cannot speak to their quality. One I have used and love is Rubio Monocoat. Monocoat is a 2-part plant oil and hardener that you mix and apply with a cloth or foam brush. It is expensive but a little goes a very long way. Use it sparingly and you’ll get your money’s worth. Monocoat creates a fantastic, low sheen, penetrating finish that is hard to beat if you like the “au naturale” look and feel. And it smells really good.

This reclaimed chestnut was first treated with boiled linseed oil to penetrate and bring out the natural beauty. Then, after drying for days, it was covered with a 2-part epoxy finish.

Tung oil is another natural oil made from the nuts of the tung tree. It provides a safe and hardened finish — but beware! Many products described as tung oil are chemical concoctions that will make you dizzy, literally. While based on tung and linseed oils, Danish oil is another brew that is usually full of pretty bad stuff.

Reclaimed cumaru finished with nothing but my homemade beeswax and mineral oil polish.

Read the Label

Perhaps the most important thing you can do is be aware of what you are buying beyond the logo and pretty pictures on the can. Many products may be packaged and named to look “green,” but read the fine print. Manufacturers are required to list the ingredients. If there are words in there you have never heard, take a minute to look them up (thanks, smartphones!). You’ll feel better knowing what you’re using — physically and emotionally — and knowing that environmentally friendly finishes add value to your work.

 

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Tim Sway

TIM SWAY is a Connecticut-based artist and maker who specializes in reclaimed, upcycled, and eco-friendly woodworking. His mission statement is to “Make Worthless Things Priceless” and he’s currently focused on making affordable and eco-ethical guitars. You can learn more about him at youtube.com/TimSway, NewPerspectivesMusic.com or timsway.net.

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