Repairing cracks and chips on the windshield - the best means and methods

Damage to car windshields includes cracks, chips and even holes. Sometimes this happens due to the fault of the air conditioner being turned on in a heated car, as a result of a temperature change. But more often than others, mechanical damage occurs from being hit by stones while an oncoming car passes. How to cope with this problem and can you do it yourself?

Today, on Chinese sites you can find ready-made kits for eliminating defects on glass. Their quality does not always correspond to what is declared, although they cost an order of magnitude cheaper and are sold in whole sets with tools. A better and more lasting effect is provided by branded polymers for cracks in auto glass, such as Pit Filler, Long Crack or Delta Kits. In most cases, the problem can be solved, but such restoration must be applied wisely. Let's see what the professionals advise on this matter.

Why repair chips and cracks?

Repairing a car that has a crack in the windshield is a mandatory step for safe driving and no problems from the traffic police. In addition to the unpresentable appearance, driving a car with a broken glass can also lead to other troubles:

1. The presence of a large crack or with a certain location poses a risk to the life of the driver and passengers. If the chip is deep, a pebble can fly through it at full speed, which will result in injury to a person. In addition, poor visibility on the road can even cause a serious accident.
2. If there are large cracks, the car will not be able to pass inspection. Since the defect can cause injury, it is impossible to obtain an inspection mark until it is corrected. According to GOST R 51709 - 2001, cars with any cracks in the wiper area and on the driver’s side are not allowed to be used. Driving such a vehicle is fraught with a fine.
3. Any crack can become longer, wider, and deeper over time. This will lead to the need for a complete replacement of the glass or its expensive repair at a car repair shop. Also, a car with damaged glass immediately loses its market value, and it will be much more difficult to sell it.

Driving a car with a crack in the glass may result in a fine.

What kind of cracks can you drive with?

You can easily drive a car that has small cracks or chips on the windshield. According to GOST, they should not exceed 15.7 cm and not have an inconvenient location for the driver. However, any chip caused by temperature changes or severe frost, as well as shock, vibration, or water will expand, so it is better to remove it immediately.

Tolerances for cracks on a car windshield

Types of damage

The cause of cracks can be either a stone hit or a minor accident. All defects can be divided into five types according to their shape and features:

1. Ray-shaped. Formed by a strong blow. They are usually long and extend to the edge of the windshield. Removal is possible if the size of the crack does not exceed 10–12 cm.
2. Rounded. The cause of the appearance is a sharp blow from a hard object. Such defects must be removed as quickly as possible with preliminary drilling, otherwise they will spread over large areas of glass.
3. Branching. Formed when hit by a heavy object or due to temperature changes. They are a whole scattering of branching rays, which is why they are difficult to repair.
4. Double sided. They look like a beam that appears from the interior part of the triplex. Most often, the car owner has to replace the glass, since such defects are almost impossible to repair.
5. Mixed (combined). Includes elements of different types of cracks. Their sealing is not always possible.

Branching crack on the windshield
How to stop the spread of a crack directly depends on its type. Usually, simple defects, chips and small dents are successfully repaired at home.

Preparatory work before restoration

Before you start repairing defects on the glass, it is necessary to diagnose them. The best solution would be to contact a professional technician for advice on whether it is worth starting this business at all or whether it is better to purchase a new windshield and not spend money on expensive polymers and tools. All factory branded windshields are made of triplex and are marked L or WL. Their main damages are as follows:

• Chips;
• Potholes;
• One-sided cracks - only on the outside of the glass;
• Bilateral cracks - on both sides of the glass;
• Radial cracks - “star” or “web”. A crack extends from one point in different directions or in a circle;
• Combined defects - a combination of several types of cracks, potholes, chips, etc.

Only a professional craftsman, having analyzed the defect, can confidently say how much the crack will be repaired, what will remain visible and how much material will be needed for the work.

DIY kits

Automotive stores offer a large number of adhesives and ready-made kits for windshield restoration.

GlassProfi

The set includes a blade, an adhesive disk, polymer glue, a fixing suction cup, and a syringe. Using a disk and a suction cup, the syringe is securely attached to the crack area, after which the glue is squeezed out of it. After 3–4 hours, the defect will become invisible and the composition will completely harden. Using this product, cracks up to 3 cm in length can be easily removed.

Contents of GlassProfi windshield repair kit

Windshield Repair Kit

This set includes the same accessories as the previous one, but is additionally equipped with a protective film. It helps eliminate defects on regular and tinted glass. When introduced, the adhesive composition completely displaces air from the crack, so the hole will be reliably sealed. This kit is recommended for emergency repairs, as the glue hardens within 20 minutes.

Windshield Repair Kit

Done Deal DD6584

The polymer composition included in this repair kit is characterized by very high strength, almost several times higher than that of cheap analogues. The product contains acrylic acid, so you need to work with it in the air and only with gloves. Glass restoration should be carried out in the shade in summer, and in winter - after preheating the damaged area.

Windshield Repair Kit Done Deal DD6584

Permatex

The product included in the kit is recommended for removing deep chips and can also be used for quick repairs in road conditions. This glue is not suitable for filling long cracks. The composition can damage the paint on the car body, so the hood must be carefully closed before repairs.

Transparent adhesive sealant for glass Permatex

WIEDERKRAFT WDK 65182

The kit includes a set of repair plates, a scraper for cleaning the crack and removing excess glue, an injector, suction cups and glue. It is better to work with glue indoors - this way it will harden an order of magnitude faster. In the summer, after applying the composition, you can expose the car to the sun's rays to speed up polymerization.

WIEDERKRAFT WDK 65182 chip repair kit

Repairing a crack in a windshield with your own hands

Before work, you need to prepare all the necessary tools and consumables and thoroughly clean the glass. Restoration is carried out only at temperatures above +10 degrees, but without using heating devices near the car, otherwise there is a risk of glass cracking. In a cold room, condensation can penetrate into the crack, which will reduce the quality of the finished seam.

Preparatory stage

First, you need to remove all dirt and dust from the crack and surrounding areas. Glass can be washed, dried and degreased, but blowing it with a pump gives an even better effect. This will allow you to remove even the smallest dust particles, which in the future will reduce the adhesion of the glue to the glass. The edges of the crack should be carefully sanded and wiped with a degreaser (acetone, alcohol).

Washing a defect on the windshield

Required materials and tools

If you purchased a ready-made glass repair kit for the job, it already contains all the necessary accessories, except for electrical tools. When completing the kit yourself, the following are usually used:

1. Polymer glue. It is absolutely transparent and looks like liquid glass. Under the influence of sunlight, the composition hardens and reliably holds the edges of the chip together. When buying glue, you need to pay attention to the polymerization time and buy the one that is suitable for a particular situation.
2. Ultraviolet lamp. Typically used if glass repairs are carried out in winter, although it will make the work easier in any case.
3. Drill with a drill for glass. The device must have a speed control function.
4. Scraper (scriber). Needed to remove dirt and debris from the crack.
5. Sharp knife. Useful for removing glue residue or dirt from hard-to-reach areas.
6. Individual protection means. For safe work, you should use gloves and a respirator.
7. Injector-syringe made of metal, plastic with a suction cup and stand. Necessary for high-quality filling of the defect with glue.
8. Magnifying glass and flashlight. They are useful for a detailed examination of the boundaries of a crack and assessing the result of its elimination.

Tools and materials for auto glass repair

Crack sealing process

First, the scale of the restoration is assessed: the crack is examined and its boundaries are determined. Next, the growth of the defect is stopped and the stress in it is reduced: a hole is drilled at a distance of 1–2 mm from the end. You need to drill glass with a drill at minimum speed and very carefully so as not to break it.

Further work is carried out as follows:

1. Fill the syringe with glue.
2. Using a suction cup and stand, attach the syringe to the point where the crack begins.
3. Carefully apply the adhesive composition directly into the defect, strictly controlling the supplied volume.
4. If you have a pump, blow it through the crack (with minimal pressure) so that the composition is evenly distributed even into the smallest cracks.
5. Remove the stand and wash it of glue.
6. Use a sharp tool to remove excess product from the surface of the glass.
7. Dry the polymer composition with an ultraviolet lamp according to the instructions (the operating time of the lamp is always indicated on the glue packaging).
8. If there is no lamp available, expose the car to direct sunlight, but the drying time will increase by about 3 times.

After polymerization of the glue is completed, polishing begins, using a special attachment on a drill or doing it manually. As a result, the surface will become perfectly smooth and will get rid of irregularities and bulges.

Required Tools

If you have decided to get rid of the defect yourself, you can purchase a special kit for repairing cracks in car windows at a specialized store.

There is everything you need here, except for the drill and polishing machine. If you purchase all the tools separately, you should collect the following list:

1. Polymer or windshield adhesive for cracks. The composition itself is quite transparent and more similar to the tint of glass. This liquid substance, under the influence of direct ultraviolet rays, begins to quickly harden, reliably gluing the edges of the chip. You can use universal or special formulations. When choosing, you should pay attention to the hardening time - you need to purchase “minimum time”. Such mixtures will help to carry out repairs quickly and conveniently.

2. Injector and bridge (plastic or metal). Designed to maximize filling of the damaged area.
3. Drill and diamond drill bit. The choice of drill is approached thoroughly - the device must operate from the car’s electrical network, and also have a speed control function.
4. Pump. At the preparatory stage, air is pumped out using a pump, and when using a polymer, additional pressure is created with its help.
5. Ultraviolet lamp. This device is necessary for hardening the poured polymer. The choice is also taken seriously - you should pay attention to the voltage and coverage area.

6. Flashlight and mirror. These tools are designed to determine the boundaries of the crack formed and the results obtained. Using a flashlight and a mirror, it is easy to determine the presence of air in the polymer, which indicates poor quality work.
7. Scriber. This tool is designed to remove all kinds of debris and splinters from the damaged area.
8. Scalpel or knife. Any sharp tool will remove any remaining polymer or other adhesive used.
9. Protective elements. Protective elements mean gloves, masks and other things that will help maintain the health of the motorist himself, as well as undamaged surfaces of the car.

Optional devices for repair include a curvimeter. This is a special tool designed to accurately measure the length of a crack, so you can accurately calculate the required amount of polymer for the job.

A curvimeter is not required to be purchased, since in most cases it is used only to calculate the cost of repairs performed.

In what cases can repairs be done?

Is it possible to drive with a large crack if it is located outside the driver’s field of view of the road? Most likely, such a car will not pass inspection, and without repair, the glass will become unusable in a short time. A complete windshield replacement will have to be done if:

• a significant piece has fallen out of the glass, or it has completely cracked, fallen apart,
• the defects are significant in size - from 20 cm,
• there is a whole network of cracks that extends from the main chip,
• damage passes through the edge of the glass, which compromises its strength,
• there are chips in the heating zone - in winter they will burst again anyway,
• the damaged area is a third or more of the total glass area.

If the damage is serious, the windshield needs to be replaced.

Do-it-yourself repair or at a car service - what to choose?

It is not possible to repair windshield cracks on your own in all cases. Here is an approximate list of situations when you can try to deal with the problem yourself:

• have glass processing skills and the necessary tools, as well as suitable working conditions,
• a small or medium scratch, crack, or chip has appeared that has not spread to large areas of the glass,
• It is possible to purchase a high-quality adhesive composition or a ready-made repair kit.

If you do glass restoration at a service center, professionals will work on it, so the result will usually be better. All work will be completed in a minimum period of time, because the craftsmen have powerful modern tools and lamps.

However, the cost of repairs can range from 1000–1500 rubles per 1 centimeter of crack, which will ultimately result in a decent amount. Therefore, it is easier to eliminate small defects with your own hands, at least in order to save money.

Windshield restoration in a car service center

Self-repair of the windshield allows you to reliably repair the defect and make it 75–90% invisible. Good adhesives are now sold in any store, so it’s worth acquiring repair skills and not having problems in the future.

Necessary tools and tools

Materials:

• Specialized polymer of varying viscosity;
• A set of translucent celluloid plates.

Tools for auto glass restoration:

• Drill with diamond conical drills;
• Scriber for marking holes;
• Scraper blade;
• Crack expander (suction cups on the rail);
• Ultraviolet lamp.