How Chip and Crack Repairs Work


Bullseyes and stars, i.e. small cracked areas in laminated glass can be repaired by the injection of our exclusive XPH3 resin which is optically matched to glass. The resin works like a glue in that it bonds the cracks, preventing them from spreading, eliminating the need to replace the whole windscreen.

When something impacts the outside of your windscreen, typically a stone, it can create a small crack in the glass - either in the shape of a star, a bullseye (round type of damage - see diagram), typically somewhere between the size of a 5 cent and a 50 cent coin, or an elongated crack, or a combination of these.

chip crack windscreen repairs

Once there is a break in the glass like this, the likelihood is that a crack will develop, particularly if it is near the edge of the glass, and/or is exposed to temperature variations or extremes. Or even if simply driven over a substancial bump. If a crack extends, depending on it's length and position, it MAY pass beyond the point of possible repair (so before it extends is preferable however, on the passenger side, cracks of a metre or more can still be repaired.)

What you are seeing, due to the altered light refraction, in one shape or another, is an "air gap" that now exists internally in the outer layer of your laminated windscreen. The aim is to fill that "air-gap" using a pressure/vacuum injection system and a resin that is optically matched to the glass, (meets Australian Standard AS/NZS2366:1999) displacing the air and reducing the reflective appearance dramatically.

If the damage is years old prior to repair, dust and contaminating material will have gradually accumulated inside it reducing the optical improvement that is achieveable with a freshly cracked screen repair. The age only affects the appearance. The strength of the repair is unaltered.

The resin possesses strong bonding properties and "glues" the cracks, preventing further cracking. With some types of repairs a tiny hole may be drilled, just penetrating the outer surface of the glass to create a passageway through which the resin is injected.

This drilling procedure is more often required though at the "live" end of a spreading crack to halt it's progress. The drill hole is then filled with clear resin to smooth and seal the surface.

An average windscreen repair takes 15 to 20 minutes. All our repairs come with a life-time warranty not to crack and for registration inspections in NSW.

Windscreen Repairs Australia - Phone - Sydney (02) 9638 1738