I guess I've been around this Cmpetition for too many years, and couldn't tell you when FIRST stopped specifically banning Plexiglass. I guess it may have happened when they limited us to the amount of certain materials, figuring the robot weight was self-limiting. However, as pointed out by several others, it is a useable material and NOT specifically prohibited by any rule this year that I can find. However, Lexan (polycarbonate) is far superior, easier to machine and work, and definitely safer in the heat of battle. It is the only choice as far as our robot is concerned where this type of material is appropriate. We have made wheels, transmission plates, and component mounts with it over the years. In addition, you can be sure that the plastic on the playing field is polycarbonate and NOT plexiglass, and for good reason
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