In this article, I cover the 6 most common options for painting the sides of a canvas. I also include a number of tips to help you decide which option is best for you. The most popular solutions that I’ve seen are to paint the edges a solid color, leave them white, or to frame the painting.
1 Leave the Sides of the Canvas White
This is the simplest option because you don’t have to do anything. If you buy canvases that are already primed with gesso, then you don’t have to paint the edges at all. You can just focus on painting the image on the face of the canvas without worrying about the sides.
You can tape the edges of the canvas with masking tape if you want a sharp line where the face of the painting meets the side of the canvas. The tape can be difficult to remove if you leave it on for too long. Look for tape that has a less aggressive adhesive.
Another issue with tape is the paint can seep underneath it as you brush it on. To prevent this, you can paint a layer of matte medium over the edge of the tape. If the medium happens to seep under the tape, it won’t show as much because it’s transparent. Once the medium dries, it will seal the edge of the tape. When you paint over it with color, the matte medium will prevent it from seeping underneath.
Keep in mind that the matte medium affects the texture of the canvas. If you paint with thin washes of colors, the areas with matte medium won’t accept the paint as well as the gesso.
The very sharp edge that the tape creates can have a mechanical feel to it, but that works with certain styles. For example, if you work in a style that consists of flat areas of color, the clean edges that you can achieve with masking tape may be what you’re looking for.
Masking tape works well on the cradled wood panels. The wood sides have a nice appearance so I don’t paint over them. I use masking tape to prevent the paint from getting on the sides.
I like to replace the the tape after a few painting sessions so it’s easier to remove. If you apply multiple coats of acrylic over the tape, you may have a difficult time pulling it off. Thick layers of thick acrylic paint may stretch and tear as you remove the tape.
If you decide to use masking tape, look for a brand that won’t leave residue behind on the painting. The masking tape that house painters use is available with a variety of adhesives. Look for one that’s easy to remove.
You don’t want to leave the tape on for too long because some of the adhesive may remain on the canvas after you peel it off. Most adhesives aren’t archival, so they’ll yellow as they age. The acids in the adhesives can also cause damage to the canvas. Test the tape out on some scraps of canvas to see how well it peels off before you use it on an important painting.
Most of the time I prefer to just paint the front of the canvas and leave the sides white. I don’t mind how some of the paint carries over to the side and creates a messy edge. It’s a subtle reminder that the image was created by smearing pigments around on a canvas.
2 Allow the Raw Canvas to Show on the Sides
If you stretch your own canvas, you have another option. You can leave the edges as plain canvas. I have done this with a few paintings. I like the look of it because the raw canvas has a warmer color than the stark white gesso.
When you prime the canvas with gesso, just paint the front of it and leave the sides as bare canvas.
The raw canvas along the edges also calls more attention to the fact that it’s a painting on canvas.
One disadvantage with this approach is that the canvas on the sides has less protection. It’s more likely to get stained or damaged. Dust can build up on the top edge of the painting when you hang it on a wall. It’s more difficult to remove dust and scuff marks from canvas if it’s not primed. But if you take proper care of the painting, then this shouldn’t be much of a problem.
3 Paint the Edges a Solid Color
There are a lot of options for colors. You can choose a color that’s predominant in the painting and use it to paint the edges.
One thing to consider is that if you exhibit a group of paintings that all have different colors on the edges, then it may become distracting. This is especially true if you choose more vibrant colors such as pink or purple. If you sell paintings online to individual collectors, then it may not matter.
Black is another option and it has a tendency to look like a black frame. It can look too stark if the painting is consists mostly of light and subtle colors.
There’s a trick to not getting paint on the front of the canvas. When I dip the brush into the paint, I start by brushing the paint along the back edge of the canvas. I avoid getting the bristles near the front edge of the canvas until there’s no excess of paint on the bristles.
Then I start brushing the paint towards the front of the canvas, as shown by the arrow in the photo above. You want to avoid going in the opposite direction because the paint can catch on the front edge of the canvas. It also helps if you keep the brush parallel to the sides of the painting.
If you decide to use black, you also have to consider the surface sheen. Black acrylic paint is typically glossy, which may not be what you want. You can find matte acrylic paint which will have a flat finish.
You can also mix Liquitex Ultra Matte Medium with regular black acrylic paint to create a very flat finish. To create a satin finish, you can add less of the medium.
Dark gray is another option. It won’t create as much contrast as the black edges and it will create a uniform look when you exhibit a group of paintings.
If you wait until after you finish the painting to paint the sides, be careful not to get it on the front of the painting. You may be able to wipe it off if you act fast enough. Otherwise you’ll have to work back into the painting to cover it up, which can be frustrating.