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How to repair a windshield crack
windshield crack
Windshield Crack

Your Car windshield can get small chips and cracks due to any speeding stone or debris on a highway or during off-road driving. You may get worried about the crack and cost of new windshield replacement. But before you go for the replacement, you should call an expert to know if your windshield crack is repairable.

You can call Auto Glass Masters to know how much it cost to repair a windshield crack or to inspect your windshield. Now let’s check how our technicians repair a crack in the car windshield.


The most important aspect of windshield repair is the proper inspection of the crack. It is very important to determine whether the damage is safe to repair, the technicians need to be certain that if he repairs the crack, it will not compromise the safety of the occupant. There are certain checkpoints that need to be passed like the type of crack, extant of damage, location of the crack, etc.

Windshield Repairable Area

Maintaining the temperature

If the technician finds that it is totally safe to repair a crack, he needs to prepare for repair. The first step is determining the temperature. For windshield repair the safe temperature range is between 10°C – 25°C. At high temperatures, the cracked windscreen tends to break during a drill as there will be thermal disorder in the glass molecules. 29°C is the highest recommend temperature where you can try for repair, but you should first try and decrease the windshield temperature using car AC.

Similarly, at low temperatures, the molecules tend to squeeze and due to the stress created due to contraction, the windshield can crack further during a drill, hence the area near the crack should be heated to get the desired temperature.

Crack Cleaning

Once the temperature is adequate for the repair, we are ready to clean the crack. There can be moisture, dirt, debris, or stone pieces inside the crack. To repair the crack it is necessary to clean all these. A drill is used to clean the crack and making a bull’s eye crack if it’s not already one. This is done to keep individual cracks and prevent it from further widening and spreading. The drill should be at 45° to avoid any kind of damage to the windshield near the crack. To prevent damage, a cover or protective drape is applied to your vehicle.

windshield Cleaning
Cleaning the crack through Drill

Resign Filling

Auto Glass Masters windshield chip repair method includes the revolutionary PRISM (pre-resin injection suspension method) technology and various techniques that involve injecting resins into the cracks with or without vacuum. Before loading the specified amount of resin into the injector, the bridge is positioned so that the injector is directly above the crack. Then the bridge is secured in place and proceeded with operating the injector to force the resin into the crack. Alternately the pressure and vacuum controls of the injector is applied to suck out air from the crack and force resin in. After the crack has been completely filled, the bridge will be removed. The resin has similar optical properties to windshield glass.

Resin Filing
Resin filling through injection


The resin used to repair a windshield is an anaerobic substance which means that, instead of air, it requires ultraviolet or UV light to dry and harden completely. The chipped area is sealed and the resin is cured by Ultra-Violet Light.

Windshield Curing
Curing through UV Rays

Resurfacing and Finishing

After the filler resin has finished curing, a sufficient amount of resurfacing resin will be applied directly to the repaired crack. This will be covered with a cellophane patch (usually supplied with the repair kit) and be cured using a UV lamp or direct sunlight. After the resurfacing resin has finished curing, the excess will be scraped off with a blade to level it out with the rest of your car windshield. Clean the area afterward with a glass cleaner.

Repair Windshield Crack

Once the windshield chip and crack area is repaired, the damaged area will not disappear completely. There will usually be a small mark in the damaged area and it resembles a small dried raindrop.

You may wonder is your repaired windshield as durable as a new one. But the windshield will be restored back to full strength and the chip will no longer be vulnerable to spreading. A windshield repair usually takes 30 minutes to complete.

Our Corporate Office

Auto Glass Masters
CB-385A, Ground Floor, Ring Road
Block CB,
Naraina, New Delhi 110028
Phone: 9278783578
Email: sales@autoglassmasters.in