Chips or cracks in windshields can cause a lot of trouble, no matter how small they are. If the chip breaks the windshield membrane, it will probably allow a certain amount of water vapor to enter the windshield and cause clouding problems. The water can also freeze and cause the chip to crack and grow larger in colder weather. But replacing the entire windshield can be expensive, and you may wonder if quick fixes like epoxy fillers are effective alternatives.
Several different types of repair resin are designed to repair windshields, many of which are made using epoxy substances. These resins can be very effective in filling in chips and preventing them from cracking, removing them to a certain extent, but some factors that determine their effectiveness. For resins to work best, they should be applied as soon as possible after the windshield is chipped, and some chips will always be too large or too deep for resins to be completely effective.
Epoxy repair resins come in different grades, ranging from 20 to 2400 cps, a measurement that refers to the viscosity of the resin. A lighter viscosity resin is useful for a very shallow crack, while thicker types are better for deeper chips. You will probably only need to choose between 20, 40, and 60 cps resins. Resins rated at 20 cps are useful for light star-breaks, while 40 is used for more serious bull's-eye cracks or cracks that have begun to branch out into different patterns, and 60 cps is used when you have a round, deep break that needs to be filled in quickly.
The general rule of thumb is that if the chip is less than 2 inches long you can repair it, but beyond that you should take it to a professional or have the windshield replaced before it spiders. Fortunately, you can buy a wide variety of epoxy kits available at auto stores. These include adhesive tapes, epoxies and syringe devices you will need to fill in the chip yourself. Some repair kits are even tailored to specific types of chips or windshield problems.
Most kits will instruct you to cover the chip with specially prepared tape that includes an attachment to attach the syringe and inject the epoxy in a series of short steps. Before you begin, thoroughly clean your windshield and make sure it is completely dry. You should also try to repair it in a warm, dry place to increase the efficiency of the epoxy bonding process.
