Artists sometimes paint unstretched canvases because they are easier to store and transport. However, that leaves a good bit of work for you to do when you purchase it. Before the piece can be framed, you have to stretch the canvas.
Things You'll Need
1x1 inch lumber sticks
Measure your canvas on all sides and make a note of the measurements.
Trace the outline of the painting on the back of the canvas to help when you are positioning the stretching frame.
Use the saw to cut each of your four pieces of lumber to the length indicated by the measurements of the canvas. The ends of the lumber should be cut at 45 degree angles.
Place the two corners of the lumber together so that the angled pieces match. Glue the pieces together and allow the glue to dry. Do this for all four corners.
Hammer a nail into each corner of the stretcher frame to make it stronger.
Place your stretcher frame in the center of the outline you drew on the back of the canvas.
Stretch the canvas over the stretcher frame. Begin in the middle of one of the longer sides and pull the canvas up over the stretcher bar. Staple the canvas to the stretcher frame.
Move to the side opposite your first staple and repeat the process.
Return to the first side and staple about 1 ½ inches away from the first staple toward the top of the piece. Staple again on the bottom side of the original staple, about 1 ½ inches down. You should have three staples near the middle of one side. Repeat the process for the other side of the painting.
Working back and forth, staple each side until you reach the top. The staples should remain about 1 ½ inches apart.
Fold the corner of the side in toward the center of the back of the canvas, like wrapping a gift. Put a staple there. Do this for both sides, at the top and the bottom.
Fold the top of the canvas over the stretcher frame, pulling tightly, and staple it in the middle of the frame. Work across the top of the frame stapling at intervals of 1 ½ inches.
Repeat for the bottom of the canvas. Tuck the corners of the top under and put a final staple on the corners.
Choose the frame you wish to have your piece in. Slide your canvas piece into the frame and secure it using the tabs on the back of the frame.