Johnson Window Films Dealer Resource Center

JWF, Rear Windows - Wet Shrink Complete

"Wet Shrink" Complete

The wet shrink method is the most commonly used rear window technique. The technique is to wet the window with solution, lay the film on the outside with the liner up and the film across the window (not up and down), trim the pattern, and then a heat gun is used to remove "fingers". Heat softens the film allowing it to shrink back to its original form before it was stretched during the manufacturing process. The release of this built up tension allows the film to shrink and form to the curve of a rear window. The finished "shrunk" pattern is then installed on the inside of the glass.

Tools Needed: Spray gun with cleaning solution, Olfa knife, Hard card, Paper towels, Squeegee, White pad, Toothbrush, Button and Heat gun

Inspect and Clean Window
Before beginning, it is very important to inspect and clean the outside of the window.
This will help prevent contamination and other possible film installation problems. Your initial steps include:

• Check for scratches and chips on rear window.
• Make sure inside rear panel and brake lights are in good condition.
• Spray outside of rear window with solution and clean.
If necessary, scrub window with white pad.
• Squeegee clean.
• If rear window has rubber gaskets, check for cracks

Cut and Trim Film Pattern
Now that you have given the rear window a good inspection and cleaning, it's now time to cut the film in order to produce the correct pattern to apply. Make sure measurements are exact so the film can be easily installed. Follow these steps:

Step 2 – place film
on window

Step 5 – spray window and film with solution

Step 7 – use heat gun to remove film "fingers"
Spray outside of rear window with solution
to make it easy to move film around.
Place film on the outside of the rear window (make sure factory edge is on the top & bottom and the liner is facing towards you) and cut a rough pattern with a 2" overlap all around to give yourself extra film in case of an error.
Next, place a button underneath the film and use it as a guide to cut the film without cutting the glass. Take your Olfa knife and poke it through the film against the button.
Most new cars have a 2" to 3" deep black border around the entire rear window frame. Your first rough cut will be to cut a pattern that overlaps the border by a 1/4" on each side, and by 1" on the top and bottom. This will provide you with extra film in case an error occurs during the shrinking process. Remove the button.
Lift half of the film on one side off of the glass and spray window and film underneath with solution. Lay the film back down on the window and squeegee across the middle. Now work the fingers out using your hand. Repeat this same step on the other half of the film.
Turn on your heat gun and let it get hot. You will use the heat gun to remove the remaining fingers and shrink the film so it will form to the glass. Note: any fingers need to be in the same direction as the factory edge (vertical in most cases).
Starting with any fingers at the top of the window, hold your heat gun approximately 2" away from the bottom of the finger and slowly apply the heat up. The heat will cause the finger to shake as it evaporates away. Smooth film out using hard card. Repeat process on all remaining fingers.
It's now time to make your final cut. Put the button back underneath the film and, using a new blade on your Olfa knife, make a cut 1/8" longer than the black border around the entire rear window.
Remove film from outside of window and place pattern onto clean trimming glass (hard coat touching glass) and trim off any bad edges.

Installation Prep
Wipe with paper towels
• After cutting and trimming your pattern, carefully prepare the rear window so a smooth and easy
installation can take place.
• Remove brake light or rear panel if necessary
• Spray inside rear window with solution and scrub with white pad. Wipe glass clean using a paper towel and clean rear panel as well.
• Spray rear window one more time with solution and squeegee out starting at the top and working your way down. Wipe clean using paper towels.

Window Film Installation
You are now ready to install your pre-cut film pattern onto the inside of the rear window.Make sure everything is clean and ready to go before following these next steps:

Step 5 – spray film and window

Step 7 – squeegee starting from the top/center

Step 12 – work out remaining film "fingers"

Finished installation
Spray inside of rear window with solution so you can move the film into place.
Go to trimming glass and peel film liner back (use tape if necessary) and spray adhesive with solution as you remove liner.
Remove film off of trimming glass and carry prepared pattern (overlapping on both arms) to the car.
Carefully enter the back seat and position film onto rear window. Check for any light gaps.
Spray the film and window with solution and use the following squeegeeing techniques to stretch the film to conform to the glass:
Start from the top center of the window and squeegee down to the bottom of the window moving across approximately 6" to 10" (depending on window size).
Next, start from the center of the window and squeegee from side to side moving down the window approximately 6" to 10" (depending on window size).
You will now have made a "cross" on the film.
Now it's time to finish off the four corners using the "British Flag" technique. Pick a corner and begin squeegeeing out the end of the corner. Repeat this process on the remaining 3 corners.
Wrap a paper towel around your squeegee and re-squeegee entire window.
If needed, wrap a paper towel around a hard card and work out any remaining fingers. The towel will absorb any moisture that comes out during this pass.
You can also use your heat gun along with a hard card on the outside of the rear window to work out any remaining fingers.

Helpful Hints:
• Always break down large fingers into smaller ones and push out to factory edge.
• Some rear windows include rubber gaskets. Trim on the inside gaskets 1/8" around window to prevent any light gaps.
• Use toothbrush to clean defroster plugs and rubber gaskets.

Inspect Rear Window Installation
• Once the film is installed, it's time to conduct one last inspection to make sure you didn't miss anything and the job was done correctly.
• Spray outside of rear window with solution and wipe clean using a paper towel.
• Let film sit for 30 min. before cleaning inside window so you don't accidentally
pull it off.
• Re-install rear panel and break light if necessary.
• Move car out in the daylight and inspect window from the outside.

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