Car Mirror Glass
Few drivers realize that they do not have to replace an entire mirror assembly should the glass shatter, break, or fall out of the various mirrors in their automobile. Instead, for a fraction of the cost of the full assembly, drivers can purchase the mirror glass separately and replace the glass themselves, saving hundreds of dollars and the headache of installing the assembly to their automobile.
There are a number of differences between car mirror glasses. These differences appear between makes, models, and even a single car itself. Did you know that the glass in your drivers side mirror is different from that in the passenger side? The passenger side mirror, despite being shaped in reverse of the drivers' side mirror also comes with different magnification. This magnification is designed to eliminate your blind spot, while discounting the difference in distance from the driver to the driver's side mirror and the distance between the driver and passenger side mirror. Passenger side mirrors are known as “convex” mirrors.
More often, new automobiles come with heated mirrors. These heated mirrors, usually engaged in tandem with the defrost work to reduce fogging or the formation of frost and ice. Heated mirrors, though not always requiring special glass, do require additional attention during the installation process. Failing to be careful in replacement may result in a broken heating element.
Your replacement car mirror glass should cost anywhere between $20 and $50 dollars, with only a few select models costing $50+ for a simple replacement mirror.
Removing Mirror Adhesive
There are a number of ways to remove adhesive that holds the glass to the mirror assembly. The first method is with brute force for mirrors that do not have a heating element, or those in which only a few small pieces need be removed. The next best method, though, is to use some kind of heater to liquefy the adhesive and make removing glass from the frame easier. This can be done with a professional hand tool such as a heat gun, or with a simple hair dryer. Keep in mind, though, that the heating element installed in heated mirrors are very susceptible to damage from excessive heat. Thus, should you use a heat gun or hair dryer on a car mirror, heat the mirror slowly and from a distance. Otherwise, drivers incur the risk of further damaging the pieces (the expensive pieces!) behind the mirror.
When installing a new mirror, do not use a cheap adhesive. Ideally, drivers will want to apply a silicone adhesive in a number of critical points on back of the mirror. The best place for this is in each of the four “corners” (six if your mirror is rounded at top and bottom) with a larger amount of glue in the center. Do not apply silicone adhesive too close to the sides of the mirror as it will then seep out from under the mirror when stuck back to the assembly.
Finally, take into consideration the amount of time it takes for silicone adhesive to dry entirely. Because there is very little room for air to move between the glass and the assembly, the silicone dries very, very slowly. Thus, it would be best to first glue to mirror to the assembly before applying tape to the glass to hold it in place. Silicone, before it dries, is a very runny adhesive, and it is possible for gravity to push the mirror toward the ground even as the adhesive dries.
Under the best conditions, the adhesive should be permitted to dry for at least one full day before use. Otherwise, drivers risk the chance that the newly installed glass will shift out of the frame or fall out entirely.