i was wondering......what if you aimed the stream of a heat gun at the plastic from a safe and effective distance! i think the breeze of heat will tighten the plastic more effectivly than boiling water.
remember i was just wondering!!!

 

Mr. Science here as many of you know:
"i think the breeze of heat will tighten the plastic"
Sorry but heat makes things expand not contract.....

 

Usually letting my car sit out in the sun for an afternoon will get rid of any creases. I wouldn't use a heat gun though. I've seen them burn right through thin plastic.

If you want to try something like that, try a regular hair dryer.

 

Not the same as the window, but what about 'heat shrink' tubing, and the ever popular toy from way back - Shrinky Dinks - remember, you would draw on the plastic - put it in the oven and they would shrink (duh) to 1/4 the original size. (useless crap from my childhood)

 

Most heat guns will reach a temperature of 750 degrees in a matter of seconds. Maybe the reason the creases go away in the hot sun is because the air has expanded inside the car.

 

Letting the car sit in the sun actually effects the top. As it "settles" the rear window may tighten slightly. As for heat shrink tubing, are you knowledgeable about cross linked thermo-plastics?

 

i say the heat softens the plastic and the creases just fall away. then when it gets cold again it re-hardens and the creases do not re-form. i've never heard of heat making canvas settle??

 

hondas2000accessories (Our sponsor who makes the front grill as well as other stookie stuff, AKA Coastal Metals) makes a perforated vinyl covered foam "noodle" that tucks into the flaps on the outside of your window. This inexpensive yet nice piece is positioned accross the middle of the window horizontally where the crease occurs.

I've had it less than a week and can tell you, it works. In combination with the hot sun, my rear window is as distortion free as if it were never lowered/folded at all.

I now lower the roof 1/2 way, then adjust the position of this piece, then lower all the way. I'll eventually learn the spot to put it and eliminate the 2-step procedure. When the top is raised, I put it in the roof well.