You may see people driving with a long crack across their windshield. The crack likely started out as a small rock chip. If left on your windshield, a chip can suddenly become a small crack that continues to grow until it reaches the edge. Here is how to handle a rock chip so it doesn't become a bigger problem.
How a Rock Chip Becomes a Crack
As soon a you spot a rock chip in the windshield, clean the area around the chip and place a piece of transparent tape over the chip. This will temporarily prevent the chip from becoming a crack.
Originally, auto glass was similar to the glass in the windows of your home. If something hit and broke the glass, sharp splinters of glass would fly into the car, injuring the driver and passengers. Auto regulations now require windshields to be made of special safety glass.
Your windshield is made of two pieces of glass laminated together with a thin plastic sheet between them. Should the windshield break, you'll get the characteristic spider web pattern on the glass, but no sharp splinters. The safety glass is also the reason a rock chip turns into a crack.
Your windshield glass expands and contracts with the temperature. A rock chip creates a weak spot in the glass. As the glass moves because of the heat, a crack may develop at the weak spot and slowly work its way across your windshield. The plastic sheet between the two pieces of glass prevent the crack from spreading out into multiple cracks so you end up with one crack that continues until it's stopped by the edge of the windshield.
Repairing a Rock Chip
Get your car in to an auto glass repair shop, such as Dale-Way Auto Body Center Corp, before the chip turns onto a crack. The fresher the chip, the easier it is for the glass technician to repair it.
They will first clean dirt and glass fragments out of the chip. A clear polymer is injected into the chip to fill it. Once the polymer has set up, the area is polished so it is clear and flush with the rest of the windshield. The technician will check that your wiper blades can move across the windshield without being interrupted by the chip repair.
Because the chip repair will prevent the replacement of the entire windshield, some insurance companies will cover the cost of the chip repair completely.