If you own a car with a rear view mirror that has fallen from the windshield, then you may have experienced the frustration of trying to reattach it using a kit or other means. Chances are high that your efforts either failed from the get-go or that the rear view mirror held up for a week or two, only to fall again. Below is how you can permanently reattach a "fallen" rear view mirror to your windshield so that it never troubles you again:

Tools and materials needed

  • Cyanoacrylate (CA) glue
  • Cyanoacrylate glue accelerator spray
  • Single-sided razor blade
  • Very fine grit sandpaper (200 or higher)
  • Acetone or methyl ethyl ketone (MEK)
  • Small glass bowl
  • Black crayon or grease pencil
  • Hex key set
  • Clean cloth or rag

Step-by-step procedure

1. Prepare your work environment - Before beginning, you should ensure your vehicle is parked in a warm, well-ventilated location. The CA glue used for reattaching the rear view mirror mount will not adhere as strongly to the windshield if the glass is cold, so either park your car in a sunny location or run the windshield defroster using its warmest setting for several minutes. Be sure to keep the windows open, and try to maintain a cross-breeze that will pass through your car while working; both acetone and MEK are strong solvents and can irritate your respiratory tract with prolonged fume exposure.

2. Remove the mounting bracket from the rear view mirror - After finding a suitable location to work, remove the mounting bracket from the rear view mirror; attempting to install the bracket with the mirror attached is unwieldy and will likely lead to failure.

To remove the bracket, look for a small-set screw in the bottom, sides or top of the rear view mirror "shoe" that connects to the bracket. Once you locate the screw, loosen it with the appropriate-sized hex key; be careful not to remove the set screw completely, or it may fall and be lost inside your car. After the screw is loosened, slide the mirror off the bracket and set it aside.

3. Clean the old adhesive from the window - Before cleaning the windshield, use a black crayon or grease pencil to mark an outline on the outside of the glass around the location of the mirror. Next, dampen a clean cloth with either acetone or MEK, and scrub the area where the adhesive from the prior mounting location lies. Take a single-edge razor blade and use it to scrape away the old adhesive residue on the glass. After you have scraped it clean, wipe down the glass thoroughly with additional acetone or MEK to remove any type of oil or other contaminants.

4. Sand and clean the mounting bracket - Fold a small piece of very fine grit sandpaper into a square and sand the surface of the mounting bracket in a circular motion. Continue sanding until all the glue residue is gone from the bracket.

Next, place the bracket inside a small glass bowl and pour enough acetone or MEK over the bracket to cover it completely. Allow the bracket to sit for at least ten minutes in the solution, then remove it and set it on a dry, clean cloth so the mounting side is facing up. Permit the bracket to dry completely before moving to the next step.

5. Glue the bracket to the glass - After the bracket dries, spray a light mist of CA glue accelerator on the windshield where the bracket will be glued. Then, spray a similar mist of accelerator on the mounting face of the bracket.

After spraying CA glue accelerator, apply one drop of CA glue to the middle of the mounting face of the bracket, then carefully lift it by its sides and push it into position on the windshield. Be sure the bracket is facing the proper direction before attaching it.

Hold the bracket in place for at least one minute, then let go of the bracket and allow the adhesive to cure for at least 2 hours. After curing, slide the rear view mirror assembly back over the bracket and tighten the set screw to hold it in position. Don't forget to remove the crayon from the outside of the windshield by scrubbing it with a dry cloth.

If your windshield needs replacing in addition to your mirror being reattached, contact a professional replacement company, such as those found at sites like http://www.mrgoglass.com. They will also likely reattach your mirror to your new windshield.