Wipe-On Varnish
Why does finishing flummox us woodworkers so much? We spend so much time planning out our projects, finding the right materials, meticulously crafting and shaping our items, just to get to the finishing stage and freeze. In my opinion, it’s because we overthink and over-complicate things. I get it. We spend so much time making something and we want the finish to be just right. Because of this, many woodworkers tend to find a finishing process that works for them and stick with it. One of the most common methods is applying a wipe-on varnish (to see a step-by-step tutorial see the video above).
First, let’s take a moment to talk about what a varnish is so we are all speaking the same language. A varnish is simply a film finish that generally contains resins to assist in the drying process. Technically, we can argue that shellac and lacquer fall into the varnish category; however, it’s common amongst woodworkers to treat these as separate categories based on how they operate. Typically, when woodworkers mention varnish they are referring to polyurethane, spar varnish, or drying oils, such as tung oil finish or Danish oil. Don’t confuse tung oil finish with tung oil. I know that sounds confusing; I’ll explain later.
Why are varnishes so popular with woodworkers? My guess is the availability and applicability. The world of finishes is filled with mumbo jumbo, jargon, and marketing speak. Every company seems to have a version of a varnish that they attempt to market as something special, and the result is shelves filled with products and a lot of blank looks on all of our faces. We do our best, we grab what we think looks good, and we try it out. Odds are, whatever we grabbed likely falls into this typically described “varnish” category. Here is a quick way to know if you are using a varnish compared to a pure oil finish. If you see a finish that contains the word “finish” in the title, it likely has some sort of resin within it to speed up the drying process. Another way to tell if you are using a varnish compared to a pure oil is by looking at the drying time. If it can dry in less than a day it probably contains resins, meaning you are working with a varnish, because it takes oils a long time to dry. This doesn’t make varnish inferior to pure oils. I rather prefer a varnish. We as consumers simply need to educate ourselves on what we are buying so we have a better chance of predicting the results.
Let’s say that you decided that you want to use a varnish for your project. How do you apply it? I know it sounds like common sense, but the first step is to read the directions on the can so you can get a feel for what the manufacturer recommends. But here is the common application procedure that I follow when applying any of these varnishes.
I sand my project to at least 180 grit. Generally, I sand with 120, then 150, and then 180. I never recommend sanding over 220 grit. Most varnish finishes need something to bind to, meaning that if the surface of the wood is sanded too finely it doesn’t adhere properly. It is also possible to burnish the wood too much so that finish can’t properly soak into the board.
I pour some of my finish into a separate container and use that when I apply it. I don’t want to keep the lid off of my main container for a prolonged period of time. Almost never do I use a bristle or foam brush to apply it. Instead, I take a small cotton rag or very thick shop paper towel and I fold it into a rectangle. I then dip the rag into my finish and apply it to my project going in the direction of the grain. It’s okay to use a circular motion to ensure proper coverage, but I always go back and make long swipes in the direction of the grain. A little finish can go a long way. Aim for no runs or drips. Most varnishes need at least three coats so apply them lightly and evenly.
In-between coats, I lightly sand the surface with 600 grit paper. I sand only enough to make the surface smooth using almost no pressure. I wipe the surface with mineral spirits and then apply my next coat. After the final coat is fully dry, I lightly sand the surface with 2,000 grit. It’s common for people to use a paper bag instead of sandpaper, but I haven’t had good luck with this because it’s not coarse enough for me.
Here are some of my favorite varnish finishes. I’ve had great luck with each of them.
General Finishes Arm-R-Seal: A great finish that gives you close to the look of a pure oil, but with added protection. It’s commonly used on surfaces that need protection such as a table top. This is my go-to finish.
Minwax Wipe-On Poly: Really similar to Arm-R-Seal. It tends to dry faster, which is a huge bonus. I don’t feel like it’s at the same level in terms of appearance. It’s a solid finish and I use it often.
Formby’s Tung Oil Finish: I find this finish to be one of the easiest to apply. It’s much thinner than Arm-R-Seal or Poly. It provides a really beautiful finish, with the downside being that it dries much slower and requires more coats than the others if you want the same level of protection.
Danish Oil: Most similar to Formby’s, but applied a little differently. Usually it requires flooding the surface, letting it soak in, and then wiping away any remaining finish (similar to applying a pure oil). It doesn’t give as much protection as some of the others and I find the odor to be unpleasant. It often comes in different colors, giving you the option to give your product a tint; a huge bonus to some woodworkers.
If you want to see exactly how I apply a wipe-on varnish, check out the video above. I hope that it helps you to dip your toe into the world of wipe-on finishes.
