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Poly windows

Posted: Wed Jan 18, 2012 7:45 am
by pablo
Just a shot in the dark. Does anyone have any idea roughly how much weight is saved between glass and poly windows?

Going to weigh the car soon once we've changed the wheels and from then I want the most from every change we make and every penny we spend.

Posted: Wed Jan 18, 2012 8:10 am
by blacky
Toughened glass density is circa 2.5g/cm3

Polycarbonate density = circa 1.2 g/cm3

So circa 50% saving.

Posted: Wed Jan 18, 2012 8:11 am
by pablo
:thumbs:

Posted: Wed Jan 18, 2012 6:11 pm
by Stuart
The polywindows* in my Sierra, so that's the rear screen, the rear quarterlights, front and back sides weighed less than 12kgs. The rear screen in glass weighed more than that on its own.

*This was 4mm macrolon cut by a glazing firm, not posh stuff.

Posted: Wed Jan 18, 2012 9:21 pm
by RX7
Isn't poly more dangerous in a crash as you can't break it to get out the car ?

Posted: Wed Jan 18, 2012 9:34 pm
by Stuart
There is that argument but I have never seen a 'proper' race car with anything other than Poly windows. I am pretty sure that with a Bart shaped hoof you could kick out most things.

Posted: Thu Jan 19, 2012 7:55 am
by pablo
The weight saving sounds great:thumbs:.
We keep coming back to the issue of safety and comfort.

As we use the car on the road to go to car shows etc. in the event of an accident glass is easier to break than polycarbonate.

Do we really want to drive that car in the summer with no opening windows.

However I am always going on about power/weight, or so Alan says, so weather permitting we will weigh the car this weekend.

I think we have agreed on a compromise, i think. We will be changing the rear doors and tailgate windows for polys.

We don't have the option of taking the car off the road as ALL of our sponsors prefer the car to be used on the road as well. More eyes looking at it. Plus the fact that Alan would probably stab me in the eye if i suggested it:headhack:

Posted: Thu Jan 19, 2012 8:01 am
by pablo
I should take this opportunity to Thank Mikeb for posting that link for poly windows:thumbs:
Cheapest place by far and a really nice guy, chatted to him about the car and even though he doesn't do our windows he is more than happy and willing to make them for us at NO extra cost.