Posted by Andy Baker at 2/12/2001 11:11 PM EST
Engineer on team #45, TechnoKats, from Kokomo High School and Delphi Automotive Systems.
In Reply to: Help Us!!!!!Please Respond ASAP
Posted by Alex on 2/12/2001 7:44 PM EST:
For FIRST robots, we cannot use acrylic (trade name "Plexiglas"
, but we can use polycarbonate.
There is a reason for this... acrylic is not tough enough. Trust FIRST, use polycarbonate. It has much higher strength qualities than acrylic. Acrylic will crack and shatter, while polycarbonate will bend and resist breaking.
As for bending, polycarbonate is great. We used it extensively in '99 for an all-polycarbonate arm made from 1/16" thick material. The HOT team built a beautiful 'bot last year, and their body (or frame) was totally out of polycarbonate. You can put this stuff in a sheet metal break and it will (somewhat) hold it's shape. Once you form it, use 1/4" long aluminum rivets to fasten it into tubes or boxes.
Polycarbonate is not only called LEXAN. There are other brands that are cheaper... look around. Hyzod is another brand name, made by Hoescht-Celenease (sp?), and Dow Chemical makes a brand. This stuff is a commodity these days. GE Plastics invented the stuff (Dan Fox, 1963), and they still make the purest polycarbonate... like the stuff that makes CDs.
Oh well, I'll stop. By the way, in a former life, I used to be a co-op at GE Plastics.
Andy B.