On occasion I will get called or have been asked to fix a chip that has a large impact point (pit). Half the time the damage has been repaired by someone else and the resin has come out of the pit. Other times the resin in the chip has deteriorated badly to the point it doesn't look like it had been repaired.

The other day was a classic case of the above. I had a customer ask me to fix damage that had already had been repaired. While the work had been done recently by an unknown party it showed all the problems encountered with a chip having a very large pit; over a 1/2" inch in diameter. It also showed some real professional ability, as it had drops of cured resin on the surface of the windshield that would interfere with the wiper blade operation.

As you can see the repair looks bad, the photo just doesn't show how bad it looked. The spot by the number 12 is cured resin.

While the safe recommendation is to repair chips with pits less than 3/8" of an inch, I limit it to 1/4" of an inch or less. About the diameter of the eraser on the end of a standard number 2 pencil. Here are the reasons why.

Chips with impact points that large usually are larger than recommended for repair. Plus surface cracks will leak while resin is under pressure. Meaning a complete fill of resin isn't possible.

Large pits go extremely deep and as such from the inside the repaired area will have a bubble appearance. Many people I deal with object to this visual flaw. Further if it extends to the point that the center laminate is exposed; repair isn't recommended.

Occasionally damage with large impact points has damaged the inside layer of glass. No repair under this situation is recommended as this is a major safety issue.

Lifting or raising of the resin happens with all resins we have seen with large impact points. This can affect windshield wiper operations that can result in a safety hazard.

Finally I know that a large pit can be filled before the repair is done so a level spot is made for an injector to seal against. It still can't correct the other problems listed.

While I know this blog is about saving money by repairing your windshield, some things can't be repaired. Like long cracks and chips with large impacts. In these instances don't waste your money get a quality, safe windshield replacement.