When starting to repair a stone break, one of the first things a professional repair technician does is determine whether or not this break will require drilling. Most professional technicians can tell at a glance whether it will be needed. If there is a bullseye (dark circles under the impact point), it will normally NOT require drilling. If, however you question whether you need to drill or not there are a few steps you can take to determine this.


The most common step to determine drilling is to take one drop of thin, stone damage resin and place it on the impact point. If you see resin seep into the break, the impact point will not require drilling. If no resin flows in, drilling is required.


Drill into the impact point if there is no bullseye. About 3-5 seconds is enough. Then using a size 14 sewing machine needle place tip in hole and tap lightly with a razor blade holder (the one shaped like a piece of gum). This will make a miniature bullseye which will allow easy access to the crack or cracks, (this technique has been used for more than a decade.) The rule of thumb in windshield repair is if it didn't fill, drill. That means any part of the break not filled with resin should be drilled and filled or your repair is worthless. When not drilling into an impact point, drill about half way through the outer layer and then tap. Do Not Drill into the Lamination, that would leave a permanent blemish.




Break Description Diagram Drilling Technique