Common Questions

I occasionally do repairs on bullseyes, which look great - almost undetectable, but the customer calls me back a few days later to say there is a ring around the outer rim. Do you have any idea why this happens?

This can happen when resin is injected into a bullseye that contains moisture. All resin shrinks a little as it cures. As the resin shrinks, the moisture, (which has been compressed), becomes visible. Always probe to detect moisture in a break, then dry it out with vacuum and/or heat before injecting the resin. Curing it under pressure will also help.

I have been doing what I consider good repairs, but too many customers are not happy with the looks of them. What can I do about this?

Without seeing your repairs I cannot comment on their quality, but will assume that they are good. It is important to address the outcome and appearance of the repair before the repair is performed. Your customers may be under the impression that the damage disappears completely. If this is the case, no repair will please them. You must set his expectations realistically.

Explain the following to them: This is a repair, not a cosmetic treatment. All breaks are different but in most cases the appearance is improved by as much as 60 to 80 percent. It will save them the cost of a new windshield and the problems that can go with an improperly installed windshield.

Is it Necessary to Drill All Breaks?

Bulls eye breaks do not need drilling. Cleaning out the impact point is necessary though to remove the crushed and impacted glass powder. Do this by using a scribe to clean out this area. Use a vacuum cleaner or small brush to remove this powder. Blowing it out will only compact it back in again.

All star breaks should be drilled. Two methods can be used. The first one being to drill all the way through the first layer of glass right up to the laminate. This works well but be advised it will leave a larger hole and cause a black spot on the laminate making this visible to the customer. Another way is to drill about halfway into the windshield of about 1/16 inch. Then insert a bulls eye needle or #16 sewing needle, and give it a tap. This will create a bulls eye connecting all the cracks together. This method not only opens an avenue for the resin to flow to all the legs at once, but makes your drill hole less visible.

What if the Injector Doesn't Seal on a Large Pit?

Start with cleaning out the pit area with a scribe. Place 2 or 3 drops of pit filler right on the pit area. Place your square of cure film on top and cure it with your UV light. When it is cured, remove the cure film. Now you have a nice flat surface to wok with. Drill a hole into the center of the pit. Set up your bridge and perform you repair as usual.

What About Using Heat?

When glass is heated it expands, thus closing up the cracks and forcing the air out. This removal of air is crucial to a successful repair, but a lot of technicians get fooled by the appearance of the cracks disappearing and assume that the break has been filled. Not allowing the break to cool down, they remove the bridge, cure the break and send the customer on his way, only to have him return a day or two later complaining that his rock chip has reappeared.

You must always let the break cool down before injecting the resin into the break. After setting up your bridge, adjust the pressure to the minimum amount. Heat the break from the inside of the windshield using a butane lighter in a circular motion for only a few seconds. Using the back of your hand, test the heated area. It should be only warm to the touch. Let the break cool down, then adjust your pressure to complete your repair.

Not waiting until the glass has cooled before injecting resin into the break will result in a flower appearing. A flower is the result of too much pressure or a windshield that is too hot. A vehicle sitting out in the hot sun must be allowed to cool down in a shop or shade before attempting repair as well as a cold vehicle being brought into a warm shop must warm up to its surroundings. As with any and all repairs or replacement, always wear your safety glasses.

What is the most important step in a windshield repair, in your opinion?

For a first-time customer, the most important step is setting his or her expectations correctly.

A new customer expects the damaged area to be invisible. He will think that if he can see it the repair is no good. You must explain before you begin, not after! Explain that it is a repair, not a cosmetic treatment. Point out that not only is it saving him the cost of a new windshield but also the loss of the original factory seal, which can never be duplicated. You could also point out the dangers posed by a replacement windshield that has been installed improperly. I believe that if two technicians each had the same skills, personality and type of territory and one followed this advice and the other did not, within a year there would be a great difference in both their income and professional reputations.

The most important step in the actual repair process is preparing the windshield for the repair. This consists of removing contaminants from the breaks and adjusting the temperature of the glass.

Solid contaminants, such as dirt, glass dust and chips, or bits of rubber from the wipers, are usually fairly easy to remove with a probe or an air spray. The most difficult contaminant to remove is water or moisture. Heat, 99% alcohol (not common rubbing alcohol), vacuum or a combination of these will help dry it out. Both vacuum and alcohol will lower the boiling point of water. Too much heat will crack the windshield, so be careful. A small hair dryer will do.Alcohol must be used very cautiously. First of all, it is very flammable and a spill on a vehicle's finish could cost you the price of a paint job. If too much pressure us used, alcohol will soften the PVB inner layer and cause permanent halo effects.

Inject a small amount of alcohol (one-half c.c. maximum) and mix it with the water using, alternately, gentle pressure and vacuum, five to ten times. Then leave it on vacuum for about five minutes. Next, using a clean, dry injector, proceed with the repair. A small hair dryer can be used on the inside of the windshield at the same time.

The safest and fastest method is to use a system with a strong vacuum plus heat.

When making an appointment, tell customers not to wash their car before you get there. Often they will so this thinking that they are helping you out.

Here are some techniques to cool a windshield:

Open all windows.

Place it in the shade or indoors.

Spray it with a 50/50 solution of water and alcohol (cover the break first).

Cool it with the air conditioner gradually (It's a good idea to ask the owner to do this).

I get a lot of callbacks from customers a couple of months after I have done a repair. The customer is concerned that the repair is failing. They tell me things like, "It looks like the break is coming back," or "You almost could not see it at first and now you can, will you come and take a look at it?" Of course I have to go back and check it out. It is almost always fine and all I have to do is buff it up a little with pit polish. This is very time-consuming, but I really cannot refuse to go look at it. How would you handle this?

This comes under the heading of "setting the customer's expectations". It is important to let them know what they can expect before the job is started, not afterwards!

Most drivers do not know what to expect their repairs to look like. If they are under the impression that the repairs will be completely invisible then nothing less than this will satisfy them. I tell them that this is a repair, not a cosmetic treatment. It will save them the cost of replacing the windshield. I add that they will be able to detect it, although it will be much less visible.

If they are very fussy and tell me they assumed it would completely disappear, I would say they will probably not be happy with a repair and that they should probably buy a new windshield and hope it doesn't get a ding in it. After considering the cost factor, they will almost always tell you to go ahead with the repair. And best of all, you have satisfied customers simply because they knew what to expect beforehand.

The same explanation after work is completed sounds like an attempt to justify a poor job.

The call-backs you are experiencing are, no doubt, due to the pit polish weathering (which it always does). This gives you two choices: Continue using pit polish and explain it will eventually weather and look a little different. Do not use pit polish, so that what customers see is the same as what they will see in a few months. They will have no reason to be alarmed at a change in appearance. Incidentally, some techs only polish dealer's vehicles.

A customer recently accused me of scratching the paint on his fender while I was stretching across it to do his repair. I am sure that I did not scratch it; it had to have been done either before or after my job. I cannot prove it, but neither can he. He is not a happy camper, to say the least. Do you have any suggestions?

Here is another case where an ounce of prevention is worth a pound of cure. The best way to win an argument with a customer is to avoid it in the first place. As long as he believes that he is right you are the loser.

Make a habit of looking the vehicle over before you begin and bring any damage to the attention of the owner. Very often he will not have been aware of the damage and would have assumed that you did it during the repair process. I doubt that many drivers would intentionally take advantage of you. There is always the possibility that another member of the family or a parking attendant had neglected to mention a little scrape or scratch, though. Many companies actually have places on their invoices where their technicians must list pre-existing damage and require the owner to acknowledge and sign it before any work is begun. I have never found this to be necessary.

Would you discuss the use of heat in the repair process? I have had a few bad experiences with customers when their windshields cracked out while I was heating the windshield during a repair. I cannot understand why it works fine sometimes and other times is a disaster.

First, you have to understand that glass, like many other materials, expands when heated. If you apply too much heat too quickly to a small area where it already has a break, the expansion will almost surely cause the crack to run.

If you are using the heat to make the resin run into the end of a tight leg remember that the crack will close up and appear to be filled, but when it cools down it will open up again. If you have your resin under pressure, the reopening will tend to suck it into the tip of the leg. Apply a small amount of heat, moving the flame or other heat source, in a circular path, quickly, around the break a few times until you see the leg(s) close. Wait until it is cool to the touch.

In summer the whole windshield is hot, so do not try to cool just the small area on which you are working.

I ran into a problem recently and would like to know how you would have handled it. I had to repair a fairly large star break on a very expensive luxury car and one leg was not connected to the pit. I did not want to drill another hole but I had no choice.

A disconnected star can be joined to the pit by inserting a sewing machine needle from the pit in the direction of the unjoined leg at a 45-degree angle and tapping it gently with a screw driver handle. It is important to get the proper angle or you could either take a chip out of the glass or pierce the laminate. Remember–the proper angle and light taps. You would be wise to practice this technique and perfect it before using it on a customer's windshield.

I occasionally am unable to completely fill one leg of a star break no matter how long I work on it. All the other legs usually give me no trouble. This baffles me because I use the same technique on every repair.

All breaks are not alike, so you occasionally must use another technique. The ability to do the difficult repairs is what separates the professional repair technician from the "hackers."

First, be sure that the cylinder on your repair bridge is not screwed down too tightly on the glass, as this could be closing the legs of the break. It only has to be tight enough to prevent the resin from escaping. If this is not the problem, then the unfilled leg is probably not connected to the pit, or is too narrow at the point where it will not flow.

With the pump on pressure, first push down on the glass with your probe at the narrow point, holding it open until the resin runs into the unfilled tip. If this fails, remove your pump and press down on the glass with your probe, between the pit and the unfilled leg. This should crack the glass and allow the resin to flow.

I am new in the windshield repair industry and one thing that has me confused is drilling. One person tells me that he drills every break and another tells me that he does not even have drill in his kit. What is your take on this subject?

Bullseyes rarely need to be drilled, but 30 to 40 percent of stars and combinations need to be. Some technicians drill them all. Their rationale is that the drill hole is smaller than the pit, so it will not be noticeable and the flow of resin into the legs is easy and fast.

I often have an otherwise excellent repair marred by a burn mark in the glass where I have drilled. Is there any way to remove this?

Prevention is the only way that I know to remedy this problem. Use a high-torque, low speed drill with a sharp bit. Drill in two-second bursts with two-second intervals between the bursts. This will keep the glass from overheating and scorching.

How do I prevent "halos" from forming around bull's-eye repairs?

This most likely will occur in hot weather when the laminate is hot. Use a thick resin and avoid excessive pressure. The halo is the result of resin being forced between the glass and the laminate.