- 1). Put on gloves and remove large pieces of broken glass by pulling them away from the window frame. Smaller fragments may have to be taken out as you remove the old glazier's compound (putty) from the frame. Use a putty knife to lift or pry out the old putty. For stubborn bits of putty that won't budge, heat them with a blow dryer to soften them, then scrape with a putty knife. Thoroughly clean the window frame and sweep away any loose debris with a sash brush.
- 2). Roll pea-sized balls of putty. Place one in each corner of the frame and a few on each side, about 6 inches apart. The putty balls will hold the window in place while you install glazier's points (small aluminum triangles that hold glass in place). Set the window pane in place and gently press the edges of the glass to adhere to the frame. To install glazier's points, hold the back of the point against the edge of the window pane with its point touching the frame. Use a putty knife to push the point into the wood until it stops. Install glazier's points every 4 or 5 inches.
- 3). Roll a handful of putty on a flat surface to make a rope about 1/4 inch in diameter. Gently press the putty rope where the edge of the glass meets the frame. Continue until the putty rope goes around the entire perimeter of the window pane.
- 4). Mix a tablespoon of dishwashing detergent into a cup of water. Periodically dip your putty knife into the mixture so the knife will glide on the window putty.
- 5). Begin smoothing the putty on one side of the window. Hold the putty knife vertically, with the blade at 45 degrees to the pane, touching both the window pane and top of the the frame. Draw the knife down the frame, pressing the putty against the frame and glass. Wipe excess putty from the blade before starting on a new section of the window. Continue until the putty is evenly installed around the entire pane.
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