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Repair of chipped car glass
Repair of chipped car glass

A small pebble accidentally flying into the windshield often causes a chip or crack to form on it. It can happen to anyone, both on the highway and on a country road. Further operation of a car with such a defect is not recommended, as it impairs visibility, reducing your safety. And if this is a crack, and even on the driver's side, you still face administrative punishment for violating the traffic rules established by law.

How to be? Change all the glass, or still try to repair the chip? Replacing a car windshield is not cheap, so if the damage is not critical, you can try to fix everything in a less expensive way. But first, let's figure out what car glass is, what types of damage it is, and what modern windshield repair is.

Chip repair
Chip repair

Chipped, cracked - what is their danger?

Types of auto glass and their features

Standard auto glass, depending on the purpose, are of two types: tempered and multilayer. The first type is usually used for rear and side windows. Tempered glass is a one-piece structure,heat treated at the factory. Its feature is the ability to crumble into many tiny particles upon impact, which significantly reduces the risk for the driver and passengers to get injured because of it. Such glass cannot be repaired, since the slightest damage leads to the destruction of the stability of its overall structure and the inevitable further disintegration.

But multilayer (laminated) structures, which are mostly used for windshields, have a completely different structure and characteristics. They are able to withstand a strong point impact without destroying the structure over the entire area. If a stone breaks through one layer, a high-quality chip repair will help restore the integrity of the windshield by 80 percent. The use of modern polymer materials will make the damaged area almost invisible.

If two or three layers are pierced, even the most qualified windshield repair is unlikely to help here. Chips, cracks, present on most of the thickness of the glass, will inevitably lead to its further destruction.

Types of windshield damage

Windshield damage is usually classified into the following types:

  • rounded chips ("bull", "wolf eye");
  • conical chips;
  • star chips;
  • chips with crushed cavity;
  • butterfly chips;
  • ray cracks;
  • round cracks;
  • bidirectional cracks;
  • combined defects.
  • Frontal chip repair
    Frontal chip repair

Now let's try to understand what is the difference between these damages, and why, if they occur, it is urgent to repair the glass. Chips, cracks and their combinations are a serious danger on the road, so do not delay their elimination.


This defect usually occurs as a result of falling into the windshield of a stone that has flown out from under the wheel of a vehicle in front or oncoming. It often happens that instead of a stone, a metal spike from a tire gets into the glass.

But is it necessary to repair the frontal chips if they do not interfere with the visibility of the driver? The chip itself, if it is, of course, small, practically does not limit visibility, but at any moment it runs the risk of developing into a crack that has several directions. The probability of this process increases significantly in winter, when the temperature is below zero outside, and heating is working in the cabin. Repair of frontal chips is also relevant before traveling on roads with poor coverage: sooner or later, vibration will do its job, and the glass will begin to crack.


The reason for the formation of a crack can be the same stone, a sharp temperature drop, as well as strong vibration. It is not uncommon for glass to crack when washing a car with cold water in hot weather, when trying to “thaw” it with hot water, or when a wheel gets into a deep hole.

Windshield chip repair
Windshield chip repair

A crack is much more dangerous than a cleavage, since the fracture itself begins to refract light, which significantly reducesoverview, as well as the fact that at any moment it can increase, dividing into several directions.

What to do if the windshield is damaged on the road

If your car has a chip or crack on the road, stop, inspect the damage and determine its cause. If it is a chip, you do not need to try to pick it out, determining the depth. It is better to rinse with water and seal the impact site with transparent tape so that dirt and dust do not get inside. If the windshield is heavily soiled, it will not be possible to repair chipped windshields.

If there is a crack, try to get to the house or to the place of repair, avoiding shaking. With strong vibration, you risk being left without glass at all.

In any case, it's better to go slower, choosing flat sections of the roadway.

Chipped windshield repair

The essence of the chip repair is to fill the chipped area with a special transparent polymer composition that glues the disjointed parts of the glass without interfering with the view. This compound, when cured, has a light refractive index close to that of glass, so there are usually no visibility problems.

Windshield repair chips cracks
Windshield repair chips cracks

Chip repair usually takes no more than 40 minutes. The process of glass restoration begins with cleaning the place of damage from dirt and splinters. If the chip has rays of more than 15 mm, through holes are drilled at the end of each of them to prevent their further propagation. Next, using a device calledinjector, the chip is filled with polymer under pressure. For its rapid solidification, an ultraviolet lamp is used. After the polymer has cured, the glass is ground and polished. Holes drilled at the end of the beams are closed in the same way.

How much does it cost to fix a chipped glass? Chip repair includes the cost of the polymer (approximately $10 per 1 sq. cm) and labor. On average, repairing a similar flaw with a diameter of 1 cm costs about $15. Not so expensive, you see, when compared with replacing the entire glass.

Crack repair

A crack, of course, cannot be eliminated, but it is quite possible to prevent its further spread. This procedure also does not take much time. The repair process consists in drilling the ends of the crack in order to relieve stress from the glass and stop its further cracking.

Glass repair chips cracks
Glass repair chips cracks

After the holes are made, they are also filled with a transparent polymer. After it dries, the glass is ground and polished.

Can I repair glass with my own hands

Today, the repair of chips and cracks, especially if they are minor, can be done at home without any problems. This procedure does not require any special skills and special equipment. It is enough to purchase a repair kit, which is sold in any auto shop, carefully study the instructions and, strictly adhering to the algorithm described there, perform a few simple manipulations.

The kits sold consist of a disposable plastic injector,a syringe with a polymer-filled nipple, a self-adhesive circle to mark the repair site, and some needles and a brush to clean the damage site.

Glass chip repair
Glass chip repair

When choosing a repair kit, be sure to pay attention to its manufacturer, recommendations for use in a particular temperature regime and expiration date. Until recently, kits made in the USA were very popular, but now the market is full of similar products made in China. It is better, of course, to purchase a branded kit, even if it is several times more expensive.

Chip on glass: do-it-yourself repair

Before starting repair work, you need to assess the size of the damage and determine the microcracks. Use a flashlight and a magnifying glass for this. If there are cracks, we drill them at the end with a thin diamond drill.

Repair of chips on a car must begin with cleaning the damage site. We clean it with a thin needle and a brush, removing dirt, dust and splinters. Rinse with water and dry with a hair dryer (construction or household). Degrease the surface with alcohol.

Next, install the injector in place: glue the circle and mount the nipple to it in accordance with the instructions. We attach a syringe with polymer to the nipple and start pumping, supplying glue to the damaged area under pressure. At the end of the procedure, the injector remains on the glass until the polymer hardens (about 6 hours).

Repair of chips and cracks
Repair of chips and cracks

When the glue hardens, its residue is removed with a blade orconstruction knife. After complete polymerization (about 10 hours), the glass must be polished. Holes at the ends of cracks are sealed in the same way.

Helpful tips for DIY glass repair

As you prepare to repair your broken car glass yourself, here are some helpful tips to help you avoid common mistakes.

  1. If the damage is of a global nature (deep chipping followed by long cracks, multiple chips, cracks on the driver side or along the entire glass), it is better to replace the entire glass.
  2. If there is a single but large chip, or a long crack that does not interfere with the driver's view, contact a specialized service.
  3. Don't trust homegrown "specialists" to repair, better do it yourself.
  4. Do not buy self-repair kits of dubious origin at a low price.
  5. If a chip occurs on the road, do not clean it, seal it with transparent tape, placing a clean piece of paper under it. Proceed carefully, avoiding uneven roadways.
  6. Don't delay repairs.

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