Before you decide that any piece of glass, from vent window to windshield, is so weatherbeaten and etched that it must be replaced, thoroughly clean it, inside and out. Use a quality window cleaner and newspaper to cut grime and greasy dirt from the glass. To remove any thick residue-such as cigarette or cigar smoke clean the glass thoroughly using a mild abrasive cleaner, like Bon Ami and water.

If there are some minor scratches in the glass, try rubbing them out using toothpaste on a clean rag, or, if there are many minor scratches as from miles of driving through blowing sand you can remove them with a glass-polishing kit. The kit contains a polishing powder that you mix with water and a felt buffing wheel attachment for your portable drill that applies and works the compound around.

Small chips can be repaired using an inexpensive kit. Place the suction-cup-held jig over the chip. Install the pressure screw in the jig. Install the outer half of the mixture injector in the jig over the chip. Then mix the repair resin and its hardener, and pour it into the injector. Force the mixture into the chip by installing the plunger into the injector.