For those of you who have read more than a couple of my posts, you’ve probably noticed that I’m not much for a simple how-to post. My writing style tends to be narrative, rather than instructional. Since I know that some folks simply want information and not a story, for this post, I will be eschewing my preferred style in an attempt to clearly communicate a method of finishing that I’ve found to be easy, repeatable, and dare I say foolproof?
I want to call the process “simple”, but some might balk at that, since there are quite a few steps involved; however, you’ll find that you spend far more time waiting for the finish to cure than actually working on the finish. A little bit of patience in between the steps will pay off handsomely in the end. All of the materials are inexpensive and readily available from your local hardware store (I tend to favor Home Depot for my finishing supplies, because they always seem to have aerosol lacquer in stock, which is the linchpin of my finishing process).
Here’s what you’ll need:
- Boiled linseed oil (or another drying oil, like walnut oil or tung oil)
- Aerosol shellac (Zinsser is the only company that makes it, as far as I’m aware)
- Aerosol lacquer, satin (I’ve used Deft for years with great results, and I’ve recently found the Minwax brand to be of similar quality)
- Sandpaper, 220- or 320-grit (Use high-quality sandpaper – Norton and 3M are excellent)
- Cork-backed sanding block
- Scotch-Brite pads (AKA synthetic steel wool)
- Healthy supply of cotton rags and/or paper towels
- Paste wax
That’s it. No expensive brushes or fancy air compressor-powered devices required. The list is still a bit long to start out, but the shellac and lacquer are the only items that can be consumed by a single project. Everything else goes a long way.
Before You Get Started
A standard disclaimer: No wood finish will ever look good if the wood isn’t properly prepared. It makes no difference how you get to “properly prepared”. You can sand, you can scrape, you can plane. I usually do all three. No matter how sharp my hand plane is, there’s always some small areas of tearout that need to be addressed with a scraper. I follow the plane and scraper with a cork-backed sanding block and 180- or 220-grit sandpaper, always making sure to sand with the grain. The sanding is nothing more than a quick rub to get an even texture before the finish goes on.
You can also use a power-sanding, which is what I did before I gained experience with a hand plane. I’m fully aware of the years of practice and the expense of the tools that were required for me to get a consistently satisfactory hand-planed surface. A random orbit sander is a perfectly acceptable tool for preparing your surfaces and it can be wielded with only a modicum of skill, so that’s where most people start. But, for the love of Neptune, please sand to a fine grit and finish up with hand-sanding along the grain, being sure to use a raking light to highlight any areas of pig-tail swirls on your wood so you can remove them.
Step 1: Start with the Oil
Alright, so now that you have a well-prepped piece of furniture, the first step is to slather it in oil like a sunbathing supermodel. This is the best part of the finishing process, because it requires no skill, and you get to catch the first glimpse of the grain in its full shimmering glory. Depending on the surface that you’re treating, you can either pour a bit of oil on the surface and use a rag to spread it around evenly (for large surfaces, like tabletops), or you can apply the oil to your rag and wipe it on the wood (for smaller surfaces, like table legs). However you choose to apply, be sure to coat the wood thoroughly. After a couple or five minutes, use a clean rag to wipe off the excess.
I start with oil for a couple of reasons. First, it should immediately highlight any problem areas that you might not have caught in your prepwork. Glue spots are a prime example – they can escape casual observation on bare wood, but will stand out like a turd in the punch bowl once oil is applied. It’s much easier to repair a blemished oil finish than a film finish. Second, the oil increases the chatoyance of figured woods like curly maple, and darkens over time, which improves the appearance of certain woods, like walnut, cherry, oak, and many exotics. You might consider skipping the oil if you’re trying to keep your wood light in color (like plain maple or holly) or if you’re using a softwood that’s prone to blotching.
The easiest drying oil to get is boiled linseed oil. You can find it at any hardware store in the solvents sections, and it works great and dries fast. If you’re wary of the metallic dryers in boiled linseed oil, you can use raw linseed oil (also called flaxseed oil), raw tung oil, or walnut oil. Just be aware that if you’re using raw oils, you’ll need to let the oil dry for a longer period of time before the next step. Boiled linseed oil will be completely dry in 24 hours. Raw oils will generally need to wait a few days to a week before you can proceed with the next step.
Step 2: Next Comes Shellac
After the oil is fully cured, wipe the wood down with a clean cloth to remove any dust and stray insects. You’ll want to wait for a clear day with low humidity for the next step, because it’s important to do your spraying outside unless you have a clean finishing room with full respiratory protection (and if you do, then why the heck are you reading this article?) Set up your furniture/parts so you can work with them at a comfortable level and move all the way around them. I find that some 5-gallon buckets and some scraps of lumber and plywood come in handy here – but make sure your setup is stable enough that your furniture doesn’t blow over in a stiff breeze!
Now spray the entire project – or as much as you can reach – with shellac, using long, even strokes. Start spraying slightly away from the furniture, then move the spray towards the piece. Don’t start spraying at the piece, because the finish can spit a little as it begins. Hold the can about 10″ from the surface, and overlap just a bit. It doesn’t take much practice to figure out what works.
Don’t spray too much in one area – shellac is dissolved in ethanol, which has a low surface tension – it’s more prone to drips on vertical surfaces than other finishes. Don’t over-spray horizontal surfaces, either, because you’ll get a bumpy texture that resembles an orange peel. Again, it doesn’t take much practice to figure out the sweet spot. After the first coat is dry to the touch, apply a second coat, then maybe a third. You don’t have to be exact, just get a good, solid base coat. Now you’re done for the day.
Why do I use shellac? Primarily, I use it as a barrier between the oil and the lacquer. Shellac is like anti-teflon. It will stick to anything, and anything will stick to it. (Almost anything). For this reason, shellac is especially helpful (almost a necessity) on woods that contains a lot of pitch (like pine) or oil (many exotics). In this case, the shellac forms a barrier between the oil and and the lacquer, so your lacquer will not have any trouble adhering even if the oil isn’t 100% cured.
Another great thing about shellac is that it dries incredibly fast. If you’re used to oil-based varnishes, like polyurethane, which are still sticky hours later, you’ll be pleasantly surprised to find that the shellac is dry to the touch in 10 minutes. Finally, shellac is a very easy finish to sand, and this is important because of the next step…
Step 3: Sand the Shellac
After you’ve let the shellac cure overnight, the finish you’ll return to will probably be a little disappointing. It’ll be quite shiny and probably a little uneven, and there will no doubt be some dust nibs in the surface as well. None of that matters, because you’re about to sand it smooth. For flat surfaces, wrap some 220- or 320-grit sandpaper around your sanding block and gently sand the surface until you get an even, dull sheen. It should feel consistently smooth to the touch. For curved surfaces, use the sandpaper without the sanding block, but use a deft touch – the last thing you want to do is sand through the shellac you’ve just applied.
When you’re confident that the finish is completely flat and level, you can move on to step 4. If you’re going for a deeper build, or if the sanding process has revealed flaws that required sanding all the way through the shellac, then go back to step 2 before proceeding. I usually move straight to step 4 at this point.
Step 4: Apply the Lacquer
Brief aside for an important warning: I can’t emphasize this enough. Lacquer contains a downright nasty brew of solvents. What exactly does it contain? Well, it depends, but here’s a list of solvents from one commercial version: Light Aliphatic Hydrocarbon Solvent, Toluene, Ethylbenzene, Methanol, 2-Propanol, Acetone, and 2-Butoxyethyl Acetate. I’m not a chemophobe, but you can look up the MSDS sheets for these chemicals and see for yourself that many of them are associated with quite unpleasant acute and chronic effects. Use your head: never spray lacquer indoors, and use a respirator if at all possible. Don’t bring the finished piece inside until it’s completely dry – at least several hours, and more is better.
Alright, I’ve just spelled out some excellent reasons to avoid lacquer. Why would I still want to use it, then? Well, simply put, I have used nearly every finish out there, and there is simply no other that is so consistently durable, attractive, and easy to apply. If they could find a way to make it non-toxic, it would be the perfect finish. Fortunately, it’s only toxic for as long as the solvent is drying, so we just have to take steps to mitigate its effects during application and curing.
Now that the unpleasantness is out of the way, let’s talk about application. You’ll basically follow the same instructions as for the shellac. Be careful to spray evenly and use a consistent sweeping motion. You should notice that the lacquer is much each to apply smoothly than the shellac. It will dry even faster. You can add another coat 5 minutes after the first. I usually give the piece three to four coats of lacquer.
Now, let the piece dry overnight. It’s best to keep it outside for several hours to let the solvents evaporate (you did choose a pretty day, didn’t you?) I bring the furniture piece into the shop before I go to bed to keep the dew off of it. The next day, the finish should be cured and should no longer stink of the chemical brew. If it still smells strongly of chemicals, let the finish dry until the smell has dissipated.
Step 5: Rub Out the Lacquer
When the lacquer has cured, it should look quite good – the best part about lacquer is how nice the finish looks straight from the can. You might be tempted to stop now and call it done – and I suppose you could – but just a couple more steps will greatly improve the tactile qualities of the finish. If you rub your hand on it, you’ll probably notice some small bumps and such from stray dust that landed in your wet finish, and you’ll possibly see some uneven areas where you didn’t spray very consistently or overlap the edges enough.
You can smooth out the bumps and even out the sheen by rubbing the vigorously with a Scotch-Brite pad. It’s just abrasive enough to give the finish a silky polish but not abrasive enough to wear through the finish. If you have a random-orbit sander, you can put the pad right on the sander and power-buff it. It works fine on large, flat surfaces. You’ll need to rub out the curves by hand. You’ll know you’re done when the surface has a consistent sheen all over and feels as smooth as silk sheets.
Step 6: Last Step, Paste Wax
Finally, get a clean cotton cloth and put a nickel-sized glob of paste wax right in the middle. Wrap the cloth around the glob of wax and squeeze it a bit until it starts to work through. Now rub all over the piece, leaving a thin, even coat of wax. After 5 or 10 minutes, the wax will dry and leave a whitish blush on the surface.
Now, buff off the wax with a dry cloth or paper towel. That’s it. The wood is finished, you’re finished, too. It should be a smooth, silky finish – with just the right amount of shine – that just begs to be touched. (I’m talking about the wood, not you.)
So there you have it. My recipe for a foolproof finish. Good luck.