Lexan?

[kentlundy]

Has anyone tried to fabricate rock guards or window protection from Lexon plastic? I have read it is easily formed and is bullet proof.

[JimGolden]

I know airplane windshields are often made from it. I believe Glasair made their windshield for the Glasair III from a 1/2" thick piece of it. I have seen a Glasair III exceed 350mph so you want something pretty stout for when you hit a bird.

It is about ten times stronger than plexiglass. When you say "easy to form", it is, but it may take you several tries to get it right. The guys that I've talked to that tried making an airplane windshield out of it usually messed up the first couple until they got the process worked out. You have to heat it up, but not too hot, then apply pressure while it's hot and get the shape you want, then hold it in that shape until it cools. So it might take you a few tries, and you'll have to build or find a pretty big oven to do this in. But, you could always start making them as a side business once you get the oven built and the process worked out

It will scratch though. But all in all, it's a great material.

Best of luck,

[Eric H]

I just worked with it for a project that was unrelated to my trailer, but it was not difficult to work with. I was working with pretty think stuff and cutting it on a band saw was the way to go. I bet you could find some aluminum channel the same width as the lexan you choose. I imagine a tint would stick to it as well so you could tint it like a regular rock guard. Also, it will bend if it's thin enough, so you could achieve the curves that were on the original guards, although I would think this would be difficult. Good luck!

[Eric H]

Originally Posted by JimGolden

I know airplane windshields are often made from it. I believe Glasair made their windshield for the Glasair III from a 1/2" thick piece of it. I have seen a Glasair III exceed 350mph so you want something pretty stout for when you hit a bird.

It is about ten times stronger than plexiglass. When you say "easy to form", it is, but it may take you several tries to get it right. The guys that I've talked to that tried making an airplane windshield out of it usually messed up the first couple until they got the process worked out. You have to heat it up, but not too hot, then apply pressure while it's hot and get the shape you want, then hold it in that shape until it cools. So it might take you a few tries, and you'll have to build or find a pretty big oven to do this in. But, you could always start making them as a side business once you get the oven built and the process worked out

It will scratch though. But all in all, it's a great material.

Best of luck,

After reading this I'm wondering if you meant forming it, or cutting pieces of it. Plexi is even easier to work with and may do the job for you.

[Melody Ranch]

It will not scratch if you use SR (scratch resistant) Lexan. I make all my flat front guards with it and use guidance from the airplane building as to cutting, sizing and drilling. Very easy to use.....and you can get it in many shade/color variations.

[dwightdi]

Lexan is trade name for Polycarbonate. It is tougher than Plexiglass, which is the tradename for acrylic. It can be heat vacuum formed similar to plexiglass but you must dry it in an oven for a couple hours at 200 - 250 for a couple hours before you raise the temperature to 325 to do the forming. You can machine, saw or drill it, but it is helpful to heat anneal it with a 300 hot air blower. You can easily measure the residual stress with polarized light and polarized analyzer. It would make an excellent guard and does come in pretinted sheet.

[garry]

I have used it to replace windows in the AS when cutting or drilling I tape both sides. It is tough but not bullet proof. You can also buy it tinted.

One of the AS windows has been in for over 6 years and no fading.

Plexiglas is a lot less expensive but it will fade and stress crack over time

Also you can install backwards since it has to be installed with a specific side toward the outside.

[Inland RV Center, In]

Originally Posted by garry

I have used it to replace windows in the AS when cutting or drilling I tape both sides. It is tough but not bullet proof. You can also buy it tinted.

One of the AS windows has been in for over 6 years and no fading.

Plexiglas is a lot less expensive but it will fade and stress crack over time

Also you can install backwards since it has to be installed with a specific side toward the outside.

Lexan is available, at an increase in cost, that is scratch resistant on both sides.

Andy

[perryg114]

You can get the scratch resistant stuff from McMaster-Carr. This stuff is not cheap. I expect you could use 1/8" poly for window guards if you had extruded aluminum channels as a frame. The 1/8" thick stuff would also bend around contours rather easily. You can also get bullet proof glass what is a sandwitch of poly with an acrylic core. The Acrylic is stronger but more brittle than poly. It is about $1000 for a 4X4 sheet.

McMaster-Carr

You can use this stuff as a frame.

McMaster-Carr

Perry