Need help with last post in thread.

Thanks.

Frank

I just ordered mine from Great Lakes aero. Got the light tint and it's great.

FWIW, although Lexan is theoretically stronger than Plexiglass, it will shatter a lot like glass if struck hard enough, whereas Plexiglass will usually just crack. Initially Lexan is clearer than Plexiglass, but Plexiglass doesn't discolor quickly if left outside in the weather; Lexan will tend to yellow after 5 or 6 years outdoors. Scratches can be buffed out of Plexiglass; Lexan scratches are more permanent. Whether that makes Lexan unsuitable or more suitable for airplane windows, I don't know.

If your plan is to just buy whatever, Plexiglass or Lexan, by the sheet and cut it, I can say unequivocally that Lexan is a whole lot harder to work with than Plexiglass. You'll need a very fine tooth saw to work with Lexan, and even then, it's easy to shatter with a power saw blade.

I think it would be better to get your windows from an aviation supplier. You might still need to do some minor trimming, but my guess is that the results would be more satisfying.

Cary

Lexan is PC. It is remarkably sensitive to quite a few chemicals you might have around the hangar and stuff in some adhesives. It will craze, fog, or swell if it comes in contact with something it doesn't like. It is slightly less pleasant to cut than acrylic.

Thickness is important. First, the s channels that retain the windows are sized properly to the original thickness. Second, noise is reduced with thickness and curvature. I'm sure anyone could make something thinner work, but you might not like the results as much as stock. Gaps with the outside sheet metal mean wind noise and whistles.

Great lakes stuff fits right in. Eliminates hassle, but costs 3x as much as flat stock. When I do it again, I'll do it with great lakes again despite potential cost savings.

The stuff at Home Depot or lowes is fine. Just get the correct thickness .125" or 1/8" for you sliver pickers. Same stuff your going to get from the airplane store. Way less expensive too. I think one sheet enough to do all four Windows. One sheet is less then one window from the airplane window stores.

Lexan/polycarbonate is awesome. It cuts with almost anything without cracking. You can beat it with a hammer and it won't crack. It will crack when cold outside and your fuel drain leaks gas on the window. That's usually a cub problem. It is also very expensive compared to plexi.
Plexi/ acrylic is very cheap. It's OEM. Won't crack with fuel. It's kinda a PIA to cut. I usually just set the old window on top of the new sheet and jig saw it out. A router also works well. Sand or scrape the ends smooth and your done.

I use lexan.

I'm not a Lexan fan unless the need for it exists (impact area/bending etc)
Lexan starts deteriorating quickly…...with gas or sun etc, also scratches very easy.
Id not recommend in a Cessna side window. They are flat. Put in Plexi like it came with. Easy, Peasy.
I did it once for a fella in the very aft ones cause he said moose horns kept poking them out. You literally cannot see through them now.

I do put in lexan on lower cub doors cause they get slammed around and dropped. Or someplace you have to bend etc but if its flat, no way.

There's a hybrid available as well. Cant remember the name. Its a coated lexan so you can get all the benefits of Lexan and not the discoloration issues. Call around you can find it. Its expensive of course.

Cheers

I grabbed some Plexi from HomeDebit when I replaced a rear window. It was a touch thicker than the stock piece but still worked.

Consider that Lexan (polycarbonate) is considered unbreakable which may impede an emergency egress from the aircraft - should the need arise.


Here are some comparisons between Lexan and Plexiglas
http://www.plasticgenius.com/2011/08/pl ... tchup.html

plexi is pretty easy to cut with a router. use the old window as a template.

I had to special order .125 plexiglass as there was none available near me other than .093 or .220. The passenger side door in my 56 C172 has a fixed window. Do I really have to drill all the rivets to split the door to replace the side window? I looked in the maintenance manual but it had no specifics on doors with fixed windows. Any idea what size rivets I'm going to need to put it back together?

The pilots window looks like it'll be a heck of a lot easier.

Thanks.

Frank

I replaced both windows on my 56 C-172 several years ago, and yes you do have to dissmantle the right side door completly to replace the window. The left door was also a PITA but I don't remember why. It looked easy but it wasn't. I used plexiglass from a local plastic shop, cost less than $20.00 for both sides. Before you start order new rubber chanel for both windows, wag aero and aircraft spruce both sell it. I did both doors in one long day, including new inside paint, it really wasn't that bad of a job. The rivets are all 1/8 inch, don't remember the length but not real long. Probabally AN470AD4-3 or 4, but I won't swear to it. Most of them can be done fast and easy with a rivit squeezer if you have one.