Johnson Window Films Dealer Resource Center

JWF, Rear Windows - Dry Shrink Complete

"Dry Shrink" Complete

The dry shrink method is the latest technique used for installing window film on compound (curved) rear windows. It's generally accepted within the industry as a superior installation technique because it takes less time to install versus the wet shrink method, and the film will last longer due to the fact that a larger portion of film will be heated, thus allowing the film to conform to the window better.
This technique is also recommended for cars with thicker defrost lines, and cars with very curved rear windows, e.g. VW Bug. The following provides you with the step-by-step process for installing window film on a rear window using the dry shrink method.

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

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

Scrub with white pad
• 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.
• 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 right pattern to apply. Make sure measurements are exact so the film can be easily installed. Please follow these procedures:

Step 1 – applying baby powder

Step 4 – squeegee solution out

Step 5 – use a button

Step 8 – heatshrink

Step 9 – lift film to spray
Making sure you stay away from the seals, sprinkle baby powder on outside of rear window. The baby powder will allow the film to slide across the glass.
Moisten the outside of the rear window in certain locations in order to secure the film to the glass and to give you a starting point to initiate the dry shrink process. Take a paper towel, wet with solution and wipe across center of the window. Now use the paper towel to wipe each side of the windows from top to bottom. This will give you an "H" pattern of moisture on the outside window.
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 pattern with a 2" overlap all around to give yourself extra film in case of an error.
Spray solution across center of the film (approximately 10" wide) and squeegee out. This will re-anchor the film to the glass before you start cutting the film.
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. Remove the button from underneath the film.
Lift one side of the pattern and wet glass with solution. Lay the film back down and squeegee across the middle and up and down the side. Repeat this step on the other half of the pattern to form a squeegee "H pattern." You should now have two large "pockets" above and below your "H" pattern providing you with a starting point for the heat shrinking process.
With your heat gun approximately 6" to 10" away from the film, heat the film at the center of each pocket moving the heat gun in a circular motion. This process will cause the film to form to the curvature of the glass. With your free hand, smooth out the area you've heated. Repeat this process until you feel the film has fully formed to the glass.
Lift half of the film off of the window and spray window underneath with solution. Place film back onto window and squeegee out solution. First squeegee should be across the middle of the film about 10" deep, then use upward and downward squeegee strokes to work out solution through the top and bottom of the pattern. After completing this process on one half of the film, repeat this step on the other half of the pattern.
If any fingers are remaining on the film, use the wet shrink method to work them out.
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 the film from outside of the window and place the pattern onto clean trimming glass (hard coat touching glass) and trim off any bad edges. If necessary, use solution to remove any excess baby powder.

Installation Prep
After cutting and trimming your pattern, the next step is to carefully prepare the rear window so a smooth and easy installation can take place.

Remove brake light or rear panel if necessary.
Step 1 – remove brake light
Spray inside rear window with solution and scrub with white pad. Wipe glass clean using a paper towel. 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 a paper towel.

Step 3 – squeegee from
top to bottom

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 2 – spray adhesive as you remove liner

Step 6 – squeegee solution out

Step 12 – remove "fingers"
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 surface of the film with solution and follow the following squeegee techniques in order to stretch the film to conform to the glass.
Using the British Flag, start from the top center of the window and squeegee down to the bottom of the window moving across approximately 10" to 15".
Next, start from the center of the window and squeegee from side to side moving down the window approximately 10" to 15".
You will now have made a "cross" on the film.
Now it's time to finish off the four corners. 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.
If needed, use your heat gun on the outside of the rear window to work out any remaining fingers.

Helpful Hints:
• Always keep the heat gun moving to avoid damaging the film.
• Use toothbrush to clean defroster plugs and rubber gaskets.

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