Professional glass repair involves a strong adhesive that a technician applies to the broken or damaged surface. The same process works with clear adhesive used at home, such as super glue. The glue dries clear and creates a near-permanent bond with the glass. When applied to a long window, a picture window or even a car window, the glue stops the crack from spreading and becoming worse. If you repair the crack properly, the glue should completely hide the crack.
Pour the acetone or lighter fluid on a microfiber cloth and rub it against the window. The acetone removes dirt and other types of debris from the glass without leaving behind any chemicals that might react with the super glue. Let the acetone evaporate.
Press the end of the super glue container against the crack and gently squeeze the tube. As the glue slides out of the tube, move your hand along the crack. Apply a long and even coating of the super glue to the crack. Let the first layer dry for several hours or overnight.
Apply a second coat of super glue to the crack in the long window. Squeeze an even layer of glue on top of the first layer. Keep applying different layers of glue, letting each layer dry, until the glue reaches just over the top of the crack.
Hold the razor blade at one end of the dried super glue. Gently wiggle the razor blade against the glue until it slides just under the edge. Pull the razor blade across the long window, scraping off any super glue above the cracked area.
Clean the long window with acetone or lighter fluid applied with a microfiber cloth. The chemical removes any excess glue from the window and naturally evaporates. The microfiber cloth gently buffs the glass and will not leave behind any scratches.