Those accordion-style sunshades press against the windshield. If not placed perfectly, they can apply uneven pressure right on the crack.
To stop a windshield crack from spreading, you should immediately seal it from debris and avoid exposing it to physical or thermal stress . While DIY methods like tape or superglue can buy time, professional resin repair is the only way to permanently stabilize the glass.
The longer you wait, the more likely dirt and moisture will contaminate the crack, making repair impossible. For the best chance of stopping a crack permanently, get a professional resin injection. For a few days of peace of mind, use a DIY kit or clear nail polish, but understand it's a stopgap. how to stop windshield crack from spreading
A small chip or crack in your windshield can quickly turn into a long, spiderwebbed mess requiring a full replacement. Temperature changes, vibrations from driving, and moisture are the main culprits that cause cracks to spread.
: Park in the shade and avoid blasting the AC immediately. Those accordion-style sunshades press against the windshield
: While clear nail polish or superglue can temporarily fill the crack, many professional technicians advise against them because they contaminate the glass and may prevent a permanent professional repair from bonding correctly. Environmental and Physical Precautions Until you can get a repair, minimize stress on the glass:
Heat is the enemy of a cracked windshield. Glass expands when hot and contracts when cold. This thermal flexing puts pressure on the crack, forcing it to grow. While DIY methods like tape or superglue can
While these methods are (except for professional resin injection), they can buy you time until a repair or replacement is possible.
Extreme temperature changes cause "thermal shock." If you blast cold AC on a hot windshield or hot air on a freezing windshield, the rapid expansion/contraction can make the crack snap across the glass instantly.
: Apply a strip of clear packing tape over the damage. This prevents dirt and moisture from entering the crack, which can make it impossible to repair later.
If you must drive the vehicle before getting it repaired, follow these rules to minimize vibration and stress: