How To Stretch a Canvas for Painting
There are several options for an artist today. Pre-stretched canvases are available in many sizes in most art supply stores. But there are times when an artist may wish to stretch their own canvases.
Begin with the frame. Some artists like to use precut frame lengths that have a fitting tongue on each end. You will need two pairs of wood (four pieces) per frame. For a 16 x 20 frame, for example, you will need two 16″ lengths and two 20″ lengths. Fit one corner together of a long and short length and tap together with a mallet. Proceed with the other pieces alternating long and short. Use a T-square or a Right-angle triangle to make sure you have hammered together a rectangle and not a trapezoid. If your frame is not in alignment, gently squeeze the two corners furthest away from each other until they are square.
To make a frame using uncut wood lengths you will need a wood saw and a miter box, or a chop miter saw. You will also want a heavy duty staple gun or V type nails made specifically for joining together two pieces of wood. You will be cutting two pairs of wood lengths. All eight ends will be cut at a 45 degree angle with the miter equipment. The longest edge of each piece will form the outer dimensions of your frame. After you have cut your pieces, put together a long and a short length and join with one staple or joining nail. Check that you have a right angle. If desired, you can clamp the wood pieces to a right angle (such as a block of wood) to assist you while you join it. Proceed with the other corners, and give a final check for right angles.
You are now ready to stretch the canvas over your frame. You will need a light weight staple gun or tacks and a hammer, and artist grade canvas. Cut your canvas in a rectangle with an extra 2″ or more on all sides of the frame, enough to pull the canvass around to the back of the frame. Place the canvas on the floor or table face down with the frame centered on it. Pull up one side of the canvas and attach with one staple or tack only, in the middle of that side on the back. Now gently pull the opposite side, and pulling so that there is no slack but it is not stretched tight, attach that canvas to the middle of the back.
Now go to the sides that are not yet done. Take one side and gently pull it to the middle of the back and attach. Avoid puckering the canvas. Take the middle of the fourth side and pull so that the canvas is like the top of a drum. You want neither too tight nor too loose. After this side is attached, start adding one staple or tack to each side, about 1 – 2 inches apart, continuing in a circle around the sides. Work your way towards the corners from the middles of each side. When you get close to the corners, neatly fold the corner. This is done much like “a hospital corner” on a bed sheet. Secure corners and your canvas is now ready for priming and painting.