Windshield chip repair is a fairly simple windshield repair that most people can do themselves. If you're very concerned about your car's appearance, or want to fix an annoying blemish in the "acute area" of the windshield, or want to prevent a chip from catching dirt or getting worse, then this will be of interest. Some states do not allow do-it-yourself chip repairs — interfering busybodies! — so make sure that it's OK to do it where you live (the folks at your local auto parts store should know.)
Note that these procedures are for chips and only for chips. Punctures through to the lamination, or all the way through the windshield, cannot be fixed by these methods. They may also not apply to the other windows of the car: check the instructions that come with the kits.
This deep, dime-size crack is
We'll describe a common and popular method of fixing chips here: see the section on kits for some sources.
Do the repair on a bright, sunny day if you can. These chemicals cure best in direct, bright sunlight. Experiments have shown that in sunlight the repair may be complete in an hour or two whereas indoors, even under powerful U/V lights, it may not be fully set overnight.
Precaution: the chemicals used in the kit may damage your paint job or the underlying metal, so cover nearby metal areas with clean rags and tape them down to ensure that an unfriendly gust of wind doesn't spread the liquid where it isn't wanted. And be careful not to get the stuff on yourself!
First, clean the windshield with ordinary glass cleaner, paying special attention to the chip itself. Let it dry completely.
Second: find the applicator disk — a flat thing with a tab. Peel the backing from it and apply the disk to the windshield, with the tab pointed UP and with the chip centred in the disk's hole. (Obviously, if the chip is bigger than the hole, you may have a problem.) Press firmly and smooth it down. Wait a few minutes for it to settle.
Third: find the applicator pedestal. It's another flat thing but it has a pointy tip like the sheaths that cover syringes. Remove the backing from it; align its tab with the one on the applicator disk (already on the windshield); press it down on the applicator disk, as accurately as you can (it doesn't have to be perfect but there shouldn't be much misalignment); press firmly and allow a few minutes for settling.
Fourth: find the syringe and remove the little cap from the business end. Insert or thread the syringe into the pedestal (as per the kit instructions.) Pull the plunger back until you feel it hit the stop; hold it there for several seconds and either let go or push it in, all the way (as per the kit instructions). Repeat 10 times (or whatever the instructions specify.)
Fifth: break time! Go away for half an hour or so. The check the chip area from inside the car to see how it looks. If there are bubbles or gaps, repeat step four as needed (again, as per the kit instructions). Once it looks good, leave the vehicle alone for the recommended setting period. (Leave the syringe and the applicator disks on the windshield.)
Finally: clear up. Remove the syringe, clean the tip and put it away; remove the disks from the windshield (using pliers or a knife if needed.) Clean any excess fluid off the windshield. Relax and enjoy the glow of accomplishment!
The repair may not be completely invisible — there may be color- matching issues or imperfections that become visible after a while; conceivably, the chemicals could break down over time. But at the very least you'll have made a great deal of difference to the appearance of your windshield.