Category: Finishing

Some of you will recall that I began work on “The Anarchist’s Finishing Manual” a few years ago, then abandoned it. Dropped it like a hot turd I did.

I’m sure that some of you think that “Big Poly” fingered me. Or I’d huffed too many VOCs (volatile organic compounds) to do the job. Here’s the real story.

For about two years, I read a lot of scientific papers and (for practical perspective) safety manuals for art schools that use finishing materials. Plus, I had many conversations with a dear friend who has devoted her life to this sort of industrial hygiene. And then I came to a conclusion.

I am not the guy to write this book. And, in fact, it might not be a book that is urgently needed for this audience.

Most of the people who read my stuff are devoted amateurs or run a woodworking business on the side. Few of my readers are professional finishers or professional woodworkers who use a lot of exotic finishing materials. Because of this, most of you are unlikely to encounter enough dangerous solvents and heavy metals to be terribly concerned.

If you simply follow the safety instructions on the can, work in a well-ventilated area (that’s key!) and aren’t finishing 10 hours a day or week, the risks are low.

Despite everything I’ve just written above, however, I still advocate that people reduce or eliminate as many VOCs and heavy metals from their shop as possible. And that is why I am posting this blog entry today.

The following manifesto – for lack of a better word – was the starting point for my aborted book. It’s how I feel about finishing. I don’t much use the word “feel.” I prefer the words “think” and “force poop.” My feelings are based on decades of living with finishing materials.

I started with spray finishing when I was about 19, but I am not an expert finisher. But I have worked with people who take finishing seriously, especially Bob Flexner and Steve Shanesy, both with Popular Woodworking Magazine. My take on the craft of finishing is different than theirs. They both came from the world of professional finishing and refinishing, where durability and surface perfection are important. As you’ll see, I live in a different quadrant.

In the end, I decided to put this opinion piece out for public consumption because I think it is the minority view. But I think it is valid, and so I’ll take my licks and continue to listen, experiment and try to become a better finisher.

And live a long damn time.  

Finishing for the Long %^&%$#@ Haul

When I talk about finishes with customers and fellow woodworkers, most are concerned about impenetrable, absolute durability. That is, how much toddler can the varnish on this table take? One toddler? Perhaps 2.3 toddlers?

I’ve always struggled when having this conversation because my opinions are upside down compared to most commercial shops, factories and (sometimes) home woodworkers. They favor polyurethane, lacquers and other hard film finishes as the armor against the army of the babies, the platoon of hot pots and the rivers of fingernail polish remover and spilled chardonnay.

Me, I prefer finishes that can be easily repaired, that look better with some miles on them and (here’s the downside) require routine maintenance and care.

I dislike finishes that form a seeming impenetrable surface film. Why? When these “highly durable” film finishes fail under duress, they tend to fail spectacularly with ugly chipping, crazing and scuffs. And repairing these durable film finishes can be difficult or impossible. Sometimes you have to remove the stuff (a health hazard), re-sand (a lung hazard) and reapply another finish (another opportunity to bathe in VOCs).

Put another way, using “durable” lacquers, varnishes and polyurethanes is like buying cheap clothing. It looks great for a while, but in a few years, it won’t be good enough for even a Goodwill donation.

So, when I choose a finish, I ignore the industry-standard scratch and adhesion tests. Instead, I separate finishes into two buckets:

1. Finishes that look incredible immediately but look like crap in 20 years (the short-run finishes) vs. finishes that look incredible when worn/abused (the long-run finishes).
2. Finishes that want me dead vs. finishes that I can apply while buck naked.

If you like math stuff, you could create an X-Y axis with four quadrants and place every finish into one of the quadrants. Perhaps I’ll do this. Or maybe it’s best if you do some of the work yourself as you ponder your favorite finishes. For now, let’s talk about what each of these categories means.

Finishes That Look Fantastic Immediately (Short-run Finishes)

My first woodworking job was at a factory that made high-end exterior doors. While part of my job was to cut rails and stiles, most of the time I worked in the finish room. Our goal was to make doors that looked great on the showroom floor and could endure the indignities of sun, rain and snow.

So, we used lots of pigments and glazes to color the wood. Plus, lots of two-part high-tech film finishes to protect the color and wood below. This finish was so nasty you couldn’t even go into the automated spray booth without a protective suit on. (What exactly was the finish? They wouldn’t say.)

But when the finished doors came out of the booth, they were stunning. Though I didn’t own a house at the time, I wanted one of these doors.

I think it’s fair to say that a spectacular finish is one of the two key ways to impress a customer (the form of the piece is the other). Customers aren’t (in general) a good judge of joinery or wood selection. But they do know smooth and shiny – thanks to plastics.

As a result, most people prefer finishes that offer the feedback of a Tupperware bowl. And commercial shops prefer finishes that are fast to apply. Combine both properties – smooth and easy – and you have a winning commercial product.

Lacquers, shellac and varnishes (including polyurethanes) all offer that plastic feel with minimal effort in the workshop, thanks to spray equipment and solvents that make them easy to apply. These finishes are, in general, quite durable in the short run. They are not likely to scratch or scuff – at first. Most are water-, heat- or alcohol-resistant – at first. And they offer low maintenance – until they cross a magic tipping point where they fail and become super ugly.

There is, of course, also the question of what the piece of furniture is used for. If you use these short-run finishes on a picture frame, an honored cabinet or decorative object that rarely gets touched, it will likely look good in 100 years if it lives in a climate-controlled environment. This is true no matter what finish you use.

So, it’s easy to see why many woodworkers prefer these short-run finishes. Heck, I loved them for many years. They look great immediately (everyone’s happy), they are fairly easy to apply (the woodworker is happy) and they take a beating for a decent amount of time.

And to be 100-percent fair, there are times when I use these short-run finishes, too. Some pieces are reproductions and need a shellac finish to be true to the original. Sometimes a customer insists on a lacquer or polyurethane – even after I explain the downsides. I’m in no way a purist. (Purity is for soap and lucky bastards with trust funds.)

Some finishes that look fantastic immediately:
• Shellac
• Lacquers of all sorts
• Varnishes of all sorts (wiping, spar, brushing etc.)
• Polyurethane (it’s also a varnish, but most people don’t know that)
• Danish oils that contain varnish
• Water-based film finishes, such as water-based lacquer and “poly” (a misnomer, but whatever)
• All-in-one stain and finish products (actually, I don’t know if these ever look “fantastic”)
• Acrylic paint
• Oil-based paint

Finishes That Look Fantastic in 20 Years (Long-run Finishes)

If you love antique furniture, you probably prize patina – the gentle wear and tear that a loved object develops after years of use. I think of patina as a combination of natural oils (from you, plants and other animals), grime, wax, paint, UV, scrubbing, scratching and burnishing.

Some finishes are ideal for building patina. Oils, waxes and soap are all finishes that tend to accumulate patina rapidly because they offer little or no protection from the real world. Interestingly, I find these finishes can be less impressive when first applied (though some people love them). For example, a soap finish on a beech chair looks like a beech chair that doesn’t have any finish on it – perhaps a little bleached. An oil finish doesn’t develop any real sheen until you apply lots of coats, such as with a gunstock finish. And wax finishes fade quickly and can get worn away.

If you want these basic non-film finishes to look great, you need to put in the hours. That means more work and more coats as you apply the finish to achieve an initial “wow” response, plus more hours of maintenance with high-wear items, such as dining tables.

But if you stick with the program, reapply a yearly coat and stay away from the dip tank and spray booth, you will end up with furniture that is as inexplicably beautiful as a weathered face.

Finishes designed to look better with age (after years of maintenance) can be difficult to sell to a spouse or customer. And that’s why our family’s dining table is covered in pre-catalyzed lacquer and – after only 10 years – is a mess of ugly flakes and crazes. The wood’s figure is almost completely obscured by the deteriorated finish.

Yes, I hate myself for this.

Finishes that look fantastic in the long run:
• Oils of all sorts (linseed, tung, walnut and other true oils that don’t contain varnish)
• Waxes of all sorts
• Oil and wax blends
• Soap
• Milk paint (be aware that a “milk” paint can be an acrylic paint)
• Paints
• Scrubbed finishes – bleach, lye and soap

Sidebar: Paint Covers Everything

One of the interesting exceptions to this taxonomy is paint. Paint can fit into every category, but that’s because there are so many different kinds of paint. It can look stunning when first applied, such as an automotive finish, then look bad when it fails. Or it can look great in 20 years, such as a real milk paint finish or a homemade linseed oil paint.

Likewise, paint can be safe enough to eat – you can make it from raw linseed oil (or eggs) plus a little dirt and beeswax. Or it can wreck your body when it’s loaded with lead.

Because we can’t make many blanket statements about paint, we’re going to need some adjectives when we talk about this finish. Latex (aka emulsion) paint is a different animal than casein paint (usually called milk paint). Oil paint is different than powder coating. Each paint has its own risks and rewards, so we’ll take a closer look at paints later in the book. (Haha, no we won’t.)

Finishes That Want You Dead or Sick – or at Least Irritated

The truth is that most of the cured finishes on the furniture in your house are inert and mostly harmless. The resins, waxes and oils in the finishes are derived from natural ingredients – wood, flaxseed, beeswax – and would do little harm if you ingested them.

The problem, then, is the solvents and additives – the chemicals that allow the finish material to flow, to be applied to the wood and to assist the finish in drying quickly and beautifully. Solvents can be mostly harmless (water) or frightening (benzene, xylene or toluene). When I consider how “safe” a finish is, I’m mostly worried about the solvents and drying agents.

Let’s take linseed oil as an example. It’s derived from the harmless flax plant, and you can buy it at the grocery store to use in salads, soups and dips. It’s not going to hurt you. In fact, it might be healthy. But when you buy linseed oil at the home center, it can be a different story.

“Boiled linseed oil” is not simply flaxseed oil that has been heated so it will dry in a reasonable amount of time. (If it were, that would be nice.) Instead, boiled linseed oil has been doctored with heavy-metal drying agents (such as cobalt manganese salt) so the oil is convenient for woodworking or painting. The drying agents turn this grocery store item into something that can make you feel sick if you breathe in too much.

Added to that is the problem that most people thin linseed oil with mineral spirits (paint thinner) to make it easier to wipe on than Mrs. Butterworth’s pancake syrup. Mineral spirits are distilled from petroleum and contain forms of benzene, which has been shown to cause cancer in animals. Mineral spirits are also an irritant to your eyes, ears and respiratory system. So even stuff that seems natural and harmless isn’t necessarily so. You have to dig a little deeper.

In the shop, my goal is to use finishes that won’t make me sick or shorten my life. That might seem like an easy task. The problem is that most off-the-rack commercial finishes are at least a little poisonous.

I wish I could list every brand of every finish here and rank them from mostly harmless to a HAZMAT. Unfortunately, finish formulas change, environmental laws change (for the better and for worse) and commercial brands come and go. When you consider buying a finish that is new to you, my advice is to look up its Material Safety Data Sheet (MSDS), sometimes called the Safety Data Sheet (SDS). These are available from the finish manufacturer and are widely published on the Internet.

Read them over and keep in mind that it’s the finish manufacturer that fills these forms out. (In other words, it’s like reading the side effects of prescription medicine). If the MSDS doesn’t scare the living crap out of you, it might be worth a go.

Oh, and there are a lot of finishes that are flammable. You’ll find that out on the safety data sheets, too. That’s also bad.

Finishes that want you dead, sick or at least irritated:
• Shellac with methanol
• Solvent-based lacquer (especially catalyzed and pre-catalyzed lacquers)
• Polyurethane and varnish thinned with mineral spirits
• Oils treated with heavy-metal drying agents
• Cyanoacrylate (super-glue) finishes
• Finishes thinned with turpentine

Finishes I Can Apply Buck Naked

I wish this were a huge category of finishes for you to explore. It’s not. Many waxes have harmful solvents. Most oils contain some heavy-metal driers. So, I have to say that most of the safe finishes are ones you make yourself. Or they are finishes that are basically raw ingredients that get applied with cleverness.

There are some manufacturers that specialize in making finishes without VOCs or other harmful ingredients. I have experience with finishes from Tried & True and Sage Restoration, though I am sure there are other manufacturers out there (or, I hope there are). The bottom line is that when searching for any finish, it’s always eye-opening to read the safety data sheet (the MSDS or SDS). Just because a label says the finish is “all natural” doesn’t mean it’s safe. Venomous spiders are all-fricking natural as well.

I’m going to be honest and say that most of the finishes in this category require a little more skill or effort to apply. They all require maintenance (if the finished object is regularly handled). And they might not be the always-shiny finish that reflects every sunbeam.

But I still love these finishes.

Many of them are rooted deep in our history and have been largely forgotten. One of my favorite finishes in this category is a pure beeswax finish applied with a “polissoir.” A polissoir is a stiff bundle of abrasive sticks – usually rush or broom corn – that is used to burnish the wooden surface with some beeswax until it is impossibly tactile and lustrous.

The downside? It’s a lot of work to burnish a large object with what is basically a bit of a broom. If you did this in a high-volume commercial shop, two things would happen. First, you’d go out of business because finishing a table this way would take a day or more. (But your pecs would look awesome.) Second, your one customer would complain the first time he or she abused the table with heat or alcohol. It’s a finish for a special type of customer (usually yourself).

Other safe finishes have yet to leap a cultural barrier. In many places in Europe, furniture and floors are regularly finished with plain old soap. Yes, the same thing you use in the shower (minus the detergents etc.). It’s a great finish for light-colored woods. But soap requires regular maintenance and doesn’t offer any significant protection.

Me, I think these finishes are worth the effort. We live in a world where everything has been formulated – processed foods to target a sweet tooth and plastics to surround us with slick smoothness. Heck, some casinos even pump their halls full of chemical smells to mask the harmful tobacco smoke and trick your brain into doing something really stupid in Las Vegas. With a donkey.

Your furniture shouldn’t be like that. It’s made from trees. It’s built with your hands. Why should we slather it at the end with synthetic chemicals that harm us? Because let’s be honest: It’s the woodworker who bears the brunt of the VOCs and heavy-metal driers. By the time the project gets to the customer, most of the harmful stuff has evaporated.

There’s one other benefit to these finishes that might not be obvious. Many woodworkers are worried about the future of the craft. As the older generation dies out, it’s uncertain if there will be younger woodworkers out there to replace them. By using safer finishes, you’ll do something to extend the craft – you’ll live longer.

Finishes you can apply buck naked:
• Natural waxes without VOCs
• Natural oils without driers or solvents
• Soap
• Oil and wax formulas (without VOCs)
• Casein paint (aka milk paint)
• Linseed oil paint (without VOCs or driers)
• Any paint that is a natural oil with safe pigments (yes, there are both safe and unsafe pigments) plus a dab of beeswax
• Some water-based finishes (check the safety data sheets)
• Shellac dissolved in ethanol (though some of you will debate me)

Most of All, Be Reasonable

I won’t lie to you, I use finishes from all four quadrants. I make a lot of different pieces of furniture for customers who have their own set of desires when it comes to a finish. I think that’s OK – it’s the woodworker who bears the brunt of the VOCs.

So, it’s up to you to know the risks of applying a finish. You need to buy – and use – the right protective gear. Avoid shortcuts. And if you ever start to feel intoxicated while finishing, know you are doing something wrong.

Also know there are always ways to make a particular finish less toxic. Substitute ethanol for methanol. Use odorless mineral spirits instead of turpentine or regular mineral spirits. Use stand oil (pure linseed oil without metallic driers) instead of boiled linseed oil.

Most of all, however, you can make your life a lot less chemical and volatile by simply opening your mind to different ways of working. A good oil-and-wax finish is easy to apply, is incredibly tactile and can be practically non-toxic. Try soap. Make your own paint. And always read the safety data sheets for the stuff in your shop. Though the safety sheets can be confusing and difficult to interpret, it’s pretty easy to determine if a finish is scary or drinkable.

My goal is build things that endure, and that allow me to endure as well. I know too many woodworkers whose bodies have been wrecked by the heavy lifting and the chemicals of our craft. I know too many who have had scares with unusual cancers. And I’m haunted by stories of fellow woodworkers who dropped dead suddenly.

I don’t want to be that person. I want to die at a very old age, in a bed I made that is finished with an oil and wax I cooked up myself.

If you have the same sort of urge, these ideas are where to begin.

— Christopher Schwarz

For shop rags, we mostly use old T-shirts that have been washed and washed and are almost falling apart. But when I have a finishing operation where I want almost zero chance of lint or threads coming loose, I break into our stash of Huck towels.

I was turned on to Huck towels by Ty Black, who used to work in my shop. His then-wife worked at a local hospital and there were always surplus Huck towels around. One common use for them is to clean surgical instruments after they have been sterilized.

Huck towels are 16” x 22”, cotton, very absorbent and a tiny tiny bit rough in texture, which makes them ideal for buffing off wax, especially when it has flashed. We use them to buff out the wax finish on our lump hammers. And when I buff out black wax on furniture, I really like the Huck towels.

Note that their threads remain intact until you cut them, then they fray and you will get stray threads everywhere.

Advisory: I am not a rag expert. Bob Flexner spent an evening telling me all about the world of rags, which has a long history. So if you are one of those people, I’m sure we’ll hear from you in the comments.

Prices vary greatly. When I buy them in bulk, I usually pay about 50 cents per. Our last bag of 50 lasted about 10 years. We washed and rewashed them until they just about disappeared.

— Christopher Schwarz

Fresh-mixed shellac is an excellent film finish, and we go through a lot of it in our shop. Here is how I mix it up for general use as a furniture finish (i.e. not as a barrier for urine, smoke or sap).

1. We use Tiger Flakes from Tools for Working Wood. There are lots of good shellac suppliers out there. But once I settled on Tiger Flakes, I stuck with Tiger Flakes. I like consistency and predictability with my finishes.
2. I use pure-grain alcohol: Everclear from the liquor store. Hardware store alcohols (which have water, methanol and/or other chemicals) don’t dissolve shellac as well. And they can be poisonous. If you can’t buy Everclear, I recommend you visit Kentucky! (Other woodworkers I know buy ethanol through medical supply catalogs and report that it’s not too much of a pain.)
3. I mix up shellac in a “one-pound cut” or even a little weaker. That is one pound of shellac per 1 gallon of Everclear. There’s a handy chart here that helps you through the math for smaller portions. While many prefer a “two-pound cut,” I prefer to apply more thin coats than a few thick coats. You can, of course, easily thin down a thick shellac.
4. I use a magnetic stirring gizmo. This $30 gadget allows me to pour the ingredients in a plastic beaker, drop in a magnetic stirbar and walk away. In about an hour it mixes the shellac completely. Some people prefer to pulverize their shellac with a grinder used for coffee beans. That works, too. I prefer the magnetic stirrer because I can pour an entire pound of shellac into an entire gallon of alcohol and walk away. No pulverizing small batches of shellac. But that’s just personal preference.
5. Then I filter the shellac through a paint filter or cheesecloth. Amazingly, the Tiger Flakes never contain any bug parts, so there’s nothing really to filter out. But I do it anyway just to be sure.
6. Then I label and date each glass jar of shellac. We use it so quickly, however, I’ve never had any expire. 

— Christopher Schwarz