Replacement Windows-(Acrylic, Perspex, Plexiglass) OR (Lexan, Polycarbonate)

[Brabham]

Hi all,

my rear windscreen has been smashed and I was going to replace it with plastic. The question is which of these two materials to use (they are grouped into their common names) and what are the properties of each ie, scratch resistance, flexibility, UV resistance etc. I would be making the screen the same thickness as original to fit into factory window rubber. The racing guys might know this. Cheers.

[Whittie]

Hey Brabham,

Lexan is good, scratch resistant and doesn't go off in the sun. It can't be heat formed to the shape of the window (read: bad fit)

Acrylic is cheaper, not scratch resistant, goes off in the sun (can polish it out), can be heat formed to the window (read: better fit) and cheaper

I went acrylic for the cost (1/3) and even got it in tinted form

The likelihood of scratching a rear window beyond visibility is pretty low and given that if you have an original to mold it to, can be formed to shape makes acrylic the clear winner, imo.

[PeterAllen]

...Lexan is good, scratch resistant and doesn't go off in the sun. It can't be heat formed to the shape of the window (read: bad fit)...

I don't have any dramas shaping Polycarbonate for headlight covers!

You would probably require a industrial oven to warm a sheet the size of the rear window.

[salty]

Brabham, lexan can be vac formed, not easy , has to done a certain way but if you can find the right vac former its easy done for those that specialize in poly-carbonite,
acrylic is easier to form and can be machine polished, like the paint on a car, it can also come's in different shades of "grey"tint .
 you could also look into PETG plastic

[Brabham]

Thanks guys might get one of each just in case. One lexan one acrylic. How do they form it? How can I polish the acrylic if it goes cloudy as the car will not be garaged. Cheers for the help.

[salty]

 both are formed, heated, using vac forming.
 can be polished with a "buff" or machine polisher, same as you would use on a car's paintwork