A crack in the windshield presents a detriment to one’s driving – mainly because it obscures your line of sight, which is a highly significant aspect in driving. A crack also makes the overall stability of an object less and less depending on the severity of damage, making it more foggy and brittle as it is exposed to additional stress and other environmental elements (like water, strong winds, hail, etc). Also, having those irregular lines in the glass exterior of your car is unpleasant to the eye. To repair cracked windshield glass, first assess – see if the chip is small enough to be repaired on your own, instead of replacing the whole windshield (the other alternative for severe damages).
A simple trick to repair cracked windshield glass, if the damage is quite small, is to use epoxy or acrylic adhesive or filler. Ensure that the ambient temperature is around room temperature. Clean and dry the small crack well, then apply the backing film. Burnish it, then place the plastic adapter and burnish again, ensuring that the adapter is oriented to fit as vertical as possible to the film. The next step to repair cracked windshield glass is to attach the syringe containing either the acrylic or the epoxy to the plastic adapter. Pull the syringe as far as it could go back and hold this vacuum for a full minute so that air in the crack will be pulled out. Then abruptly let go of the syringe to force adhesive into the crack.
Repeat this alternating cycle of vacuum and filling to virtually obliterate the space and fill it with adhesive. That’s to repair cracked windshield glass when cracks are small, confined and are just chipping of the glass.