How To Stretch a Canvas

Step 1

Cut your piece of canvas at least 6-8 inches wider than the dimensions of the stretcher bars (taking into account the frame's depth). You'll need this extra canvas to have something to get a grip on to be able to pull and stretch it.

Step 2

Lay your frame centered on top of the canvas you've cut.

Step 3

Make sure that the grain of the canvas is lined up straight with the stretcher bars.

Step 4

Start with the longest side of the canvas. Fold it over, and plop down three staples with your heavy duty stapler near the center of that stretcher bar.

Step 5

Rotate the canvas. Or go to the opposite side and pull rather tight, fold the canvas over the frame, and put down three more staples near the center of that stretcher bar(exactly like the first side).

Step 6

Go to one of the unstapled sides and give the canvas a good solid pull, fold it over, and put in two staples.

Step 7

Go to the opposite and last unstapled side and pull the canvas very tight, fold it over the frame, and give it a few staples there as well.

Step 8

Go back to the first side and working from the centers to the corners, pull a piece of the loose canvas over the stretcher bar (generally standing/kneeling from the opposite side) putting in two staples or so for each section (depending on the size of the frame).

Step 9

Go to the opposite side of the canvas and repeat the previous step.

Step 10

Continue pulling and stapling pieces of the canvas moving around the canvas edges in the same order as above. If you want, you can staple near the corners and then place a staple between the center and the corner, instead.

Step 11

Continue until you have about four inches of unstapled space from the corners.

Step 12

Fold the corners however suits you best and staple them down. One way that works is to tuck them under twice so that one straight edge is just even with the corner.

Step 13

Pull the corners very firmly, as this is the final tightening you give the canvas and the most important.

Step 14

Once you're finished, flip the whole canvas over and tap it with your finger. It should sound like a drum. It should be very, very taut. If there is any creasing or strange pulling, you'll be able to see it from here. If you mis-stapled or don't have the canvas particularly taut, pull the staples and fix it. The canvas will sag far worse once it is painted.

Step 15

Pound in each staple with a hammer until it is flush with the wood.

An artist explains stretching a canvas.

Tips

The most important part is to make sure the canvas fibers run square to the frame. If they don't, the bars will twist and two opposite corners will lift up.
Tearing the canvas will make a straighter line than cutting it will.
Pull the canvas tight with your fingers, then use a good quality gesso. The gesso will tighten the canvas further as it dries.
Note: regular desk staplers are not heavy duty enough to hold the canvas. You need a heavy duty staple gun.
There are special pliers (with a wider surface to avoid pulling holes in the canvas) made for stretching canvas. They are available at art supply stores.
After canvas is stretched, put shims/wood wedges into corner to further stretch canvas.
Using an ordinary spray bottle filled with plain water, dampen the back of the stretched canvas. As it dries, it will shrink and thus tighten the canvas even more.
Unprimed canvas is easier to stretch than primed (ungessoed)canvas.