This is a topic that never seems to get much attention in the art podcasts, online courses, live streams, and other conversations where artists talk about their art practices. At least not the ones I've followed or taken. Even when it is brought up the conversation seems to focus only briefly on whether oil or acrylic painters prefer to wrap the painting around the edge of the canvas or not. Then the topic drops and they move on to 'more interesting' things like finding a personal style, mindset, etc., and I'm left thinking "But wait! What about all the other options? What about selecting side colors? What about wood panels? What about finishes other than paint? Do I have to finish the sides at all if I'm framing the piece?" After being disappointed over and over by this lack of information on how to finish the edges of my wood panels I decided I was just going to have to figure out what worked the hard way - trial and error.
My paintings are encaustic, and this medium has some unique challenges. The main being that it is primarily wax and therefore not a lot of other mediums will adhere to it properly. Meaning, that if any paint bleeds under the taped sides of the panel it's possible an edge finish that isn't compatible with wax is doomed to flake, chip, or be repelled from the offending spot leaving a blemish. So that significantly narrows the choices available to me. Artists painting with acrylic and oil have more options, but it is still worth noting that your edge finish must always be compatible with your painting medium to avoid a potential disaster.
So after I tossed out any type of acrylic, latex, or polyurethane finishes from my list of compatible mediums I was left with basically three options: oil paint, shellac, or more encaustic. I then crossed off oil paint because of the drying time. I'm simply not patient enough to wait days for each layer to dry. That left two: shellac or more encaustic.
Now, before I continue on about how I finish my wood panels, I want to mention why I think it's important to always finish the edges of paintings, even if framing. It's simple really...because, as an art buyer, I want a finished edge. A finished edge tells me that the artist cares about their work enough to complete a piece properly. Also, because my work goes into floater frames there is always a bit of the edge showing in the gap between the work and the frame. I want the glimpse of the side to be as presentable as the face of the painting. Finally, I understand that the majority of art hangs in homes, and even if I choose to frame a piece my buyer may later choose to remove the frame. They should have that option if the unframed piece works better with their decor. I don't want my buyer to remove the frame and find the unfinished pine sides of a cradled panel. So I always finish the edges of my paintings, even if going into a frame.
On to the actual finishing. Back when I painted in acrylic I did continue the painting over the sides of the canvas. I love this look, especially on deep cradled canvases. It gives someone approaching a painting indirectly a tiny preview of the piece. This works particularly well for paintings hanging in a hallway or a foyer, where the viewer is seldom facing a painting directly. In these situations the most common view of the work is from the side, where the edges count the most. I want my encaustic pieces to have this same intentional edge. I want it to be obvious that I intended that work to be seen from all directions, not just straight on.
After a lot of testing, I decided my favorite edge finish for wood panels is shellac tinted with dry pigment. Shellac dries very fast, and is naturally quite thick so it only takes two or three coats to get a beautiful finish. Shellac is a natural resin dissolved in alcohol. It only comes in two colors, clear and amber. Both can be tinted easily. Without any pigment it dries to a gloss finish, but adding a bit of dry pigment softens the gloss and results in a lovely satin sheen that pairs beautifully with the luster of the encaustic paint. Surprisingly, I found I like tinting the amber shellac more often than the clear. Mostly, because I'm typically going for a shade of brown, and the amber provides a rich warm base to start with. I don't have to use as much pigment, and the colors are richer. I have found when using the clear that I have to use more pigment, and it's harder to get a deep color without over pigmenting.
I wait to finish the sides of my wood panels after the encaustic painting is complete and the protective tape on the sides has been removed. To prime the sides I make sure I've scraped off any errant encaustic medium, and then carefully sand the wood with fine grit sandpaper, being very careful not to hit the encaustic edge of the painting face. I wipe any sanding dust away with a damp rag and let the sides completely dry. Then I pour a bit of shellac into a paper cup. The amount depends on how many paintings I'm finishing that day. Then I tint the shellac by stirring in very small amounts of dry pigment, adding just a little each time until I get the color I want. I don't measure, and every batch is different, so if I need paintings to have the same edge colors, like for diptychs or triptychs, then I wait and do them all at once with a single batch of tinted shellac. I've found it's best not to use more than a teaspoon ( 5g ) or so of pigment to about a 1/4 cup ( 60ml ) of shellac otherwise it starts to get grainy and too matte. These are rough estimates.
I apply the tinted shellac with a sponge brush, and load enough on the brush to get most of the edge with a single continuous swipe. Shellac starts to dry quickly so it is important to not go over your strokes more than once or twice or it can leave thick goopy spots that are impossible to fix until it is dry and you sand it off. So the rule is to work quick and with long even strokes. I've found that it is always better to do more very thin layers than trying to save time by doing thick. Thick layers dry unevenly and can drip or shift while drying. Once all four sides are done I'll set the painting horizontally on something that keeps all four edges from touching the worktop surface, otherwise the shellac can adhere to whatever it is touching. I typically just place a few empty encaustic paint pots on the table and set the painting on those. I repeat this for all the paintings I have queued to finish, and then wait about 30 minutes before checking if they are dry enough to start the next layer.
It is important to lightly sand the edges, by hand, in between each layer of shellac to get a smooth finish. I recommend using a very fine sand paper for this, and just gently go back and forth over the edge in the direction of the grain of the wood for a few swipes. I use 220 grit. Don't use an electric sander. It is too powerful and will just strip off your entire finish, or worse, accidentally damage your painting. All you are trying to do is knock back the raised, pebbly bits of the finish so the next layer goes on smooth. After sanding, wipe the edges with a lint free dust rag and apply the next layer using the same long, uninterrupted strokes. I will repeat this shellac, sand, wipe down process two or three times until I'm happy with the opacity and smoothness of the finish. Each successive layer will make the finish more opaque, so it's important to know when to stop.
The other option I have is to use more encaustic medium on the edges. This only works for very small paintings where the weight of the work won't damage the finish if it's set on its side. I do not use encaustic for any paintings larger than 6x6 inches ( 15x15 cm). And even then I only use it on rare occasions when I want a very specific look. I never leave encaustic drips on the edges, as those are very delicate and easily break or chip.
Finally, there is another option that I just recently started using. Wood veneer edge banding. This material is used in furniture making. You may have seen laminate versions used to finish the ends of countertops in a kitchen or bathroom.
Edge banding comes in 25' or 50' rolls that are typically 1" or 2" wide. This makes it perfect for 7/8" or 1.5" cradled wood panels. It comes in a variety of beautiful real woods like walnut, maple, cherry, and more. It is thin enough to cut with a razor knife. I highly recommend the pre-glued variety, as it bonds instantly with heat. The unglued variety needs a bonding agent that typically requires an extended dry time and clamping. Using clamps on a cradled panel is near impossible, so just buy the pre-glued and save yourself the extra work and time. For detailed information about applying edge banding it is easy enough to search YouTube for information. Many furniture makers have excellent tutorials. The only caveat I will mention is that I always apply edge banding to the wood panel before I paint. This is because it is applied with heat, and would be near impossible to apply without melting the encaustic edge of my painting. I apply the banding to the panel, and then tape the edges of the panel just as I normally would before painting. After the painting is finished, I remove the tape, scrape off any errant wax, give it a quick sand and apply a few coats of clear shellac.
I hope this information is helpful for anyone who, like me, wished online art discussions would focus just a bit more on the practical steps of creating a piece of art. Even if it's the boring bits like finishing the edges of a paintings.