Johnson Window Films Dealer Resource Center

JWF, Shrinking SF

Shrinking Security Film

Shrinking security film on a rear window is a little different than shrinking standard automotive films. Since the film is much thicker, it takes a longer amount of time to correctly shrink the film. If you are installing thinner safety film, like a 2 mil or 4 mil piece, you can revert back to the standard rear window shrinking procedures for automotive films. This section provides helpful tips on how to shrink 7 mil and thicker security films.

Tools Needed: Spray bottle with cleaning solution, Masking tape and Heat gun

After you've cut your security film pattern, use masking tape to attach the film to both sides of the rear window. This keeps the film from curling away from the glass and prevents the film from burning during the heat shrinking process.
With a strong heat gun, start heat shrinking the film. Don't be impatient, it takes a lot of heat to shrink 7 mil or thicker security film. Start heat shrinking from the center of the glass, making sure to keep the heat gun moving at all times. Be very careful during this step because it's easy to burn the film since there is no moisture underneath the pattern.
As you're heating the film, you will begin to see the film form to the shape of the glass. Smooth out the film with your hand as you continue to heat shrink the film.
After the film has shrunk as much as possible, lift up one side of the film and spray with solution. Lay the film back onto the glass and squeegee the film out. If you have any small fingers left, finish them off using the wet shrink technique.
Now, repeat the same process on the other side of the film.

• After shrinking is complete, cut off the excess film from the top and bottom of your security film pattern.

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