Every repairable break is unique, and some repair professionals say a break or chip is like a snowflake. However, windshield breaks share certain characteristics that allow us to put them in generalized categories. These categories are bullseye, half-moon, star, crack and combination. The National Windshield Repair Association (NWRA) developed a standard for windshield repair called the Repair of Laminated Automotive Glass Standard (ROLAGS) and had it sponsored by the American National Standards Institute (ANSI). It uses the following categories for repairable breaks:
- Star break,
- Stress; and
- Combination break.
The bullseye break is usually the easiest to repair. The outcome is the most pleasing to the customer because it almost completely disappears. However, many techs use the bullseye to demonstrate the repair process because of the ease of repair and pleasing results. This break is usually caused by a dull, slow moving projectile. Dull projectiles cause circular breaks because of the circular “grain” in annealed glass. Only sharp, fast moving projectiles would overcome the circular “grain”, like star breaks or cracks.
A half-moon break is an unfinished bullseye and is caused by an even slower moving dull projectile. Normally half-moons are a little harder to repair because the resin must be forced to the far reaches of the break.
One method of speeding up a half-moon repair is a procedure called refracturing. Some use this method because it makes the break bigger. Since a bullseye repairs so well and the end result is almost invisible, the refracturing technique creates a full bullseye from the half-moon. A tech can use a darning needle or pointed pick and place it directly into the pit of the break. Then they can use a weighted device and tap the needle or pick until the half-moon becomes a bullseye.
This same technique can be used on both the star and the crack repairs as well. You create a bullseye at the base of the pit which makes the repair faster and easier.
Star and crack breaks are caused by sharper and faster moving projectiles. These are typically harder to repair because of the break’s narrow “legs”. It also doesn’t appear as transparent as the bullseye or half-moon. When the break is properly repaired the finished “legs” of the break appear as fine “spider web like” lines when viewed head-on.
The last category of break is the combination break, which is usually caused by a large projectile. The windshield can be hit so hard that the cone of the break is pulverized, causing a star break within a bullseye. The finished repair appears to look like a repaired star break since the bullseye disappears, but the star within the break repairs like a typical star break.
Before any repairs are accepted or completed make sure your customer understands the process and what to expect. Refer to the ROLAGS Standard below: https://rolags.com/pdf/ANSI+NWRA+ROLAGS+001-2014.pdf