Glass can just as easily chip as paintwork can. Unfortunately, repairing chipped glass is a bit more difficult then repairing chipped paint. Chipped glass repair requires skill, tools, experience and patience. It is often done by trained people for best result.
Why chipped glass
Chipped glass happens when interaction between a hard object and a glass surface results in a piece of glass being chipped off from the surface of the glass. One of the most common causes is a piece of stone hitting the front windscreen on the motorway. The stone is small, but hard enough to damage the glass. The glass is to strong to break, but not strong enough to fully absorb the impact without any structural damage. A small piece of glass from the surface breaks off.
How to repair chipped glass
There several options when you want to fix a chipped windscreen:
Some people decide to save on the expense of getting it repaired, and just ignore the damage. Over time, dirt can get into the glass, making it irreparable. It is also a weakpoint in the glass, which is often the point where cracks form.
Getting it repaired by filling
The chip can be professionally filled by a glass-technician. The technician will clean the glass and apply a special type of clear sealant. This fills in the hole and after curing, will be almost as hard as the glass around it. If done properly, the damage to the glass will be almost impossible to see with the naked eye. Many insurance companies offer free glass-repair if the damage is not to great.
Replacing the windscreen
Although the filling technique has improved greatly in the last decades, there are still those who don’t trust a once broken windscreen, and decide to get it replaced. This a much more expensive job, but will result in a perfect windscreen again.
There are several shops (online and offline) that sell DIY kits to repair your glass. Although these often result in an “acceptable” finish, they will not be as good as professional tools and products, and might cost you more then needed (seeing as many insurance companies cover this type of damage).
When and how to repair chipped glass
Fixing chipped glass is not easily done. The process might not take up much time (many companies offer a “while-you-wait” service), but that doesn’t mean it is easy. Repairing chipped glass is best done as soon as possible. If you wait to long the chip can grow, it can trap dirt inside (which affects the quality of the repair) and it can affect your safety.
The image below shows the average sizes that companies consider safe to repair:
Zone A: damage up to 10 mm
Zone B: damage up to 15 mm
Zone C: damage up to 25 mm
Zone D: damage up to 40 mm
*the size is measured in the widest part of the chip from edge to edge.
How the repair is done
Although not every company uses the exact same technique, tools or product, this is the generally used method by most companies.
- The glass is cleaned thoroughly. This is very important to achieve a good result
- The chipped area is covered with a special device that creates a vacuum.
- Once the vacuum is created, the chip is filled with special resin
- A special UV-light is used to harden the resin, this usually takes several minutes
- Once the resin is completely cured, any excess resin is removed
- The glass gets a polish to leave a perfectly smooth finish
- The glass is cleaned
The danger of chipped glass
Besides it being a possible MOT failure, a glass chip can also leak to cracks, which means the windscreen needs to replaced. In some cases it can also affect your vision while driving, making it possibly dangerous to be driving around. A chip can also grow in size, meaning it could become to big for an easy repair.
Get it done by professionals
The products used by professionals require experience and training to get the best result. This can be taught to most people, but it will require practice. Most people who want to fix a chip in their windscreen have never done this task before, decreasing the chances of a successful repair. Getting it done by a professional is not very expensive in most cases. Consult with your insurance company, because it is possible that they cover the repair. The company who performs the repair will often handle any paperwork for you, meaning there is nothing you have to do.