[simpits-tech] lexan, etc

[Fred Mahone]

Lexan, the bullet resistive plastic, is a different animal than the 
acrylics and other forms of clear plastic.

Some grades have a scratch resistant outer layer for use as window glaze 
and view ports. The heavier grades for safety glazing
has a softer formulation so that projectiles will expend excessive energy 
trying to get through it as the lexan heats, softens and then
grips the projectile.

The window glaze type, I believe, is also graffiti resistant. This means 
paints and inks will not adhere very well and can be readily removed.

I took a 3/4 inch thick piece of the safety version to the range and fired 
a .40 S&W police type round at it. Tore it out of the wood stand, but the 
bullet did not penetrate, just a slight bulge on the reverse side. Being 
slammed into the sand and red clay by the bullet impact did not make any marks.

The stuff we use at Tech is Optiplex. I have experimented with it to see 
how it will be for making panels. I have tried bead blasting and sanding to 
compare the frosted effect. The bead blasting does a very even but coarse 
frosting. 600 grit paper used for wet sanding auto finish and used with 
water seemed to be the smoothest and finest frosting. I lay the paper, grit 
up, on a piece of aluminum. Wet it well and place the Optiplex on it and, 
using light pressure, do a figure "8" pattern.

I am going to question the people at the ALEA convention that display 
renovated panels as to more information and will take a lot of photographs. 
This is getting interesting!

If anyone would like to try some Optiplex, we have a lot of scrap from 
making chemical hoods and environmental chambers.

Fred Mahone