How to fix window pains
Wearing gloves, pick out the broken glass. If the window is sealed with a gasket, first pull the gasket out of the frame. (Wear goggles.) Run a screwdriver around the frame to remove small shards. Scrape off the old glazing compound and pull out the points or the spring clips. Sand the groove and coat it with linseed oil.
If the points you remove are straight bits of metal, get new ones with horizontal tabs. Straight points are hard to install without breaking the glass.
Buy or cut a new pane 1/8 inch smaller in length and width than the opening. Apply a thin bead of glazing compound along all four sides of the frame and press the new pane into place. Replace the spring clips or secure the pane with points spaced 4 to 6 inches apart. Use the putty knife to press the points halfway in. If necessary, tap the putty knife with a hammer.
Roll glazing compound into a rope about 3/8 inch in diameter, press it along the edges of the pane, and draw a putty knife over it to form a triangular bead. Let the compound dry for a week, Paint it, overlapping the glass about 1/16 inch to seal out moisture.
If your window had a gasket, don’t use glazing compound. Lay the new pane in the bare frame. Press the gasket under the lip of the frame with your thumb, starting at a corner.