Get a replacement windshield for your vehicle. These can be bought new or repaired in a car shop, where you have to check the windshield very well first to see that it has no cracks before delivering the money. If you are going to remove the windshield of your vehicle, use many elements to cushion, such as blankets and quilts to prevent damage the change. If it’s second-hand, the windshield may not fit the car. You will have to eliminate the existing rubber or reduce it to approximately 1 mm deep. This is very easy using a razor blade.
Remove the surrounding part of the plastic and upper moldings properly. You should not remove the clips with which they are attached, these clips are small pieces of plastic specific to the vehicle and its moldings. This saves time, but if it is not the same model you will have to paste them if the clips have no replacement. You will save time and around $ 5.00 for the clips. Most are simple and totally aesthetic, they are only an inch of plastic which is attached to the windshield. They do nothing for the windshield, except to improve their appearance. Some are extremely complex with clips and plastic clamps that secure the molding firmly to the windshield.
Cut the urethane from the outside between the glass and the body, using a cold knife. Depending on the tools used and the experience, this can take from fifteen minutes to an hour. The urethane that holds the windshield in place is flexible but very resistant; which helps the glass to move but does not crack due to the tension exerted when driving.
The main problem with this method is that the previous installation has perfectly adjusted the glass to the body and this does not allow enough space for the blade to enter, which could cause the glass to break. Often, pieces of glass will fall into the defroster’s vent to be ejected later.
Cutting the windshield from inside the vehicle is the other option. With a special razor cut the urethane with a repeated drag movement. Many installers use cutters that are faster, but do more damage to the metal of the vehicle, scratching the paint on the body area is not a problem if the stripe is painted with a body layer that must be compatible with the urethane. You can do the job with a sharp kitchen knife, if you do not have the tools – but this makes it a very difficult job and can take many hours.
This material is resistant, up to 1000 psi. Practice is the key, how much pressure should you put on the razor blade without breaking it. How much time to make the movements and so that you do not slip and damage the dashboard. With practice you can do it faster.
Prepare the body. Clean any visible dirt with a brush and then simply with water. The old urethane has to be reduced to approximately 3mm in thickness. Use a knife for any rusted area or areas with loose / damaged urethane will have to be carved to the metal. These areas of rusted metal should be removed.
Prepare the glass with a special base for the urethane adhesive. The purpose of the base is to open the molecules of the strip of synthesized material (the black band around the perimeter of the windshield) this is done to prepare the glass to accept the urethane molecules. If your installer is in a hurry, he’s ignorant or he just does not care if your windshield goes off, and he’s going to skip this step. After the crystal is activated, the molding is fixed to the glass and the urethane is as follows:
- Apply the urethane with an electric putty gun. It is best for the new urethane to adhere to the old urethane. It must be clean and free of dust, oil or other contaminants. One of the problems that installers have is when the wind blows dust to the body before the urethane adhesive has been applied. The work can be done without an electric gun but it is much more difficult to achieve a consistent line, so there is more chance of leaks.
- Place the windshield, carefully align the top bottom and sides with the naked eye. Some vehicles have the mounting block for the lower part of the windshield to rest, others do not. Be careful not to touch the frit band because the oils and dirt on your hands can contaminate the activated glass and reduce the effectiveness of the activator. Use gloves, either latex or nitrile, to prevent contamination.