How To Fix Small Cracks & Chips in Your Windshield
Your car’s windshield is subjected to a number of impacts, scratches and other incidents that can cause damage. A minor crack or chip is easily caused by a flying stone, gravel or accidental impact. Without prompt care, these minor issues can lead to spider cracks across your entire windshield. Learn how to fix a cracked windshield and where to turn for reliable DIY repair kits.
Determine the Size of the Crack
Before you order a kit or perform any other repair steps you need to identify the extent of the damage. A chip smaller than a quarter and a crack shorter than 3 inches can be easily patched with an epoxy repair kit, but a larger crack or chip may need a professional product or a complete replacement windshield. Be sure your kit fully covers the size of crack of chip on your vehicle before starting the repair process.
Measure your windshield damage and determine the extent of the issue. If the damage is more severe, talk to an associate at your local AutoZone for alternative solutions before you attempt to use a standard repair kit. Using a kit on damage larger than recommended can result in a compromised windshield.
Choose a Repair Kit
Compare kits from various brands to find the best option for your windshield. Many brands offer similar products, so use these features to choose a quality kit for your needs:
- Acceptable crack or chip size
- Expiration date
- Curing steps
Epoxy has an expiration date, so be sure you use a kit that isn’t too old for proper adhesion. Look for an expiration date or a manufacturer’s date and try to use a kit that’s 6 months old or less.
Some repair kits have many complicated curing steps or require additional tools or special features, like outdoor use only, so be sure you have all the necessary equipment for your particular repair option. Every packaged kit has its own specific instructions, so be sure to compare the following guide with the instructions included in the kit to ensure proper use.
How to Fix Windshield Cracks
Clean the Area
One of the first steps of how to fix windshield chip is to clean the glass around the area. Any dirt or other debris in the chip or crack can compromise the patch and create imperfections in the glass. Use a microfiber towel and a small amount of rubbing alcohol to wipe the surface. Use care, since the edges of a crack can be sharp. Be sure the area is completely dry before applying the patch.
Apply the Patch and Pedestal
Take the paper backing off the patch and line it up with the damaged area of your windshield. A chip or crack larger than the circle cutout on the patch is too large to be properly patched with this particular kit.
Next, center the patch over the damaged area and place it on the exterior of your windshield. Most patch kits include a pedestal. This molded plastic piece has an angled tube for easy epoxy application. Line up the tabs and press the pedestal against the adhesive.
Use the Included Epoxy Resin
Some resins require mixture, while others come pre-mixed or mix as you apply it. Fill the pedestal with liquid resin and use the syringe to compress it completely down into the pedestal. Once the syringe is fully compressed, carefully hold the pedestal as you pull back up on the plunger.
If mixed correctly, the epoxy in the pedestal won’t be pulled back into the syringe. Draw the syringe fully up without pulling it out of the pedestal. Some kits have a small clip to prevent this from happening. Other kits require you to watch the position of the syringe. Don’t let the syringe pull out completely or you won’t create the necessary vacuum.
Drawing up the plunger causes a vacuum to form in the syringe. The vacuum isn’t strong enough to draw up the epoxy resin, but it can encourage air bubbles to escape from the cracked area.
Wait for the Air Bubbles To Escape
Watch for signs of air bubbles escaping and wait for the allotted time recommended by the kit. This can be anywhere from 1-10 minutes. Don’t remove the syringe until you no longer see air bubbles forming and being drawn out of the resin. Depending on the amount of air bubbles, this can feel like the longest step in how to repair windshield chip.
Remove the Syringe and Pedestal
After all the air bubbles have left the area, push the syringe plunger down again to force the remaining resin into the crack. You may only get the syringe halfway down the pedestal before it stops. Carefully knock on the window with your knuckles and press the syringe once more. Don’t force it; this time it should only move about half an inch.
Once the allotted time has passed and the epoxy has cured, carefully remove the syringe, patch and pedestal. You may need to put an additional drop on the top of the crack to ensure there’s no dimple or dent from application.
Use the Curing Strip
Most repair kits come with a curing strip for the final layer. Place this on the crack carefully to avoid air bubbles. Hold the strip in place and squeegee any remaining air bubbles. Let the strip rest for the recommended time in the instructions before scraping it off with a razor blade. Don’t rush this step or attempt to remove the strip by hand, but use care to scrape it off for a clean finish.
Remove Excess Epoxy
Scrape off any remaining resin with your razor blade. Use care to avoid any fingerprints or damage to your windshield. As you carefully scrape off the remaining resin and curing strip you should have a flawless windshield.
Shop for Repair Kits Today
Enjoy quality DIY windshield repair kits at your local AutoZone location. Talk to a qualified professional about the pros and cons of each type of kit. Use these steps and the included instructions to enjoy a professional finish that prevents large cracks from forming and restores the look and protection of your windshield.
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Be sure to consult your owner’s manual, a repair guide, an AutoZoner at a store near you, or a licensed, professional mechanic for vehicle-specific repair information. Refer to the service manual for specific diagnostic, repair and tool information for your particular vehicle. Always chock your wheels prior to lifting a vehicle. Always disconnect the negative battery cable before servicing an electrical application on the vehicle to protect its electrical circuits in the event that a wire is accidentally pierced or grounded. Use caution when working with automotive batteries. Sulfuric acid is caustic and can burn clothing and skin or cause blindness. Always wear gloves and safety glasses and other personal protection equipment, and work in a well-ventilated area. Should electrolyte get on your body or clothing, neutralize it immediately with a solution of baking soda and water. Do not wear ties or loose clothing when working on your vehicle.
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