REAR WINDOWS - One Piece Installtion
- Warning -
Never use a heat gun on laminated glass such as windshields and certain Mercedes Back glass.
The only way to avoid using strips on a compound curve window is to use the heat shrinking method. It involves using a heat gun to shrink the excess film along the grain (toward the factory edge) and smoothing it out with a rolled up paper towel, hard card wrapped in paper towel, or a wool gloved hand. Keep in mind that the film will only shrink properly toward the factory edge, with precut tint the factory edge for rear windows is on the top and bottom. We'll go over 3 different heat shrinking methods here; Wet Shrinking, Powder Shrinking, and shrinking with dryer sheets. All three methods require the use of a heat gun. A hair drier will not work as it does not get hot enough.
On an oversized piece of tint laying on soapy water on the outside of the back window with the liner still in place facing up, squeegee a horizontal achor onto the film to bring all the excess film into 'finger' shapes on the top and bottom of the window.
Pass the heat gun over a finger quickly, just until you see the film react, smooth that area flat with a rolled up paper towel, hard card wrapped in paper towel, or a hand that is wearing a wool glove, then do the same thing with the fingers that pop up on either side of the one you just smoothed flat, and so on. After the film is all flat repeat the procedure with a hard card instead of a gloved hand or paper towel. Peel the liner off, spray heavily with solution and install on a prepared rear window.
Unheated Finger on Left, heated finger ready to smooth on right.
Squeegee a horizontal achor to bring the excess film to the top and bottom
A hair dryer will not get hot enough, you must use a heat gun on high setting! You are only shrinking the finger itself, just pass the heat gun over the finger quickly until you see it distort slightly, then smooth it out. If you spend just a moment too long over the finger it will burn or shrink unevenly. The trick is not to crease the film when you smooth it, so the first time use a rolled up paper towel or a hand wearing a wool glove to smooth the finger down and to keep the wet film against the glass, otherwise larger fingers will bind and crease if you use the hard card first.
VERY IMPORTANT! The film will only shrink properly if the fingers are aligned with the grain of the film. As you unroll the film from side to side the proper grain direction is up and down. The fingers will need to face up and down along the top and bottom of the precut tint. Fingers always need to be moved to the factory edge. Squeegee a horizontal anchor onto the glass to anchor the middle and sides, moving all the excess film to vertical fingers.
DRY SHRINKING - BABY POWDER METHOD
Using baby powder wiped onto the glass instead of water will allow you to heat shrink large areas instead of fingers one at a time. This is known as Dry Shrinking and is very difficult to master, but will allow you to do most windows in one piece much faster than the wet shrinking method. The following series of pictures shows a tinter doing a dry shrink on a Toyota Camry rear window.
When Anchoring the film just let it go where it wants, just make sure all the horizontal fingers are moved to the vertical. Usually most the excess will be towards the sides.
This is the pattern of heating that I use. It allows for more even shrinking rather than trying to tackle one finger at a time. I heat a circled area, then smooth with my hand wearing a wool glove. The circled areas are about 3 inches square.
DRY SHRINKING - DRYER SHEETS AND FABRIC SIZER TECHNIQUE
A dryer sheet heat shrink is a lot like a baby powder shrink, but instead of using baby powder, spray some water on the outside of the window and wipe a dryer sheet all around so that it deposits the fabric softner onto the window. Let it dry and it will leave a residue. If you are using fabric sizer, spray it on, wipe it around and let it dry. Now lay the precut tint over with the liner facing up and anchor horizontally as if you were doing a normal dry shrink, but DO NOT use water under the anchor... you won't need it. The film will now stick to the glass when smoothed as if it were wet, but the fingers don't stick as if there was dry powder underneath. Shrink it similar to a baby powder shrink, but only smooth areas down that are shrunk. The beauty of this method is accuracy in distribution of shrink, no need for follow up wet shrink and no mess from baby powder. It takes some practice though and is about as difficult to learn as dry shrinking was from wet.