unofficial: Use of Lexan and ABS

@jcgrif, in the Official Judging Q&A asked this:

“There is some question that has arisen based on the use of plastic on a robot. Can a single robot use both the Lexan and ABS plastic sheets as long as the total surface area of the plastic does not exceed 288 sq inches (12” x 24" = 288" sq) or could be cut from a single sheet of the material. If all of the pieces could be cut out of a single 12x24 sheet of Lexan, could you cut several of the pieces out of ABS and use the ABS parts instead of the Lexan. So a single bot would have both Lexan and ABS, but the total area would still be cutable from a single sheet of one or the other material.

R7 States -
Non-shattering plastic from the following list; polycarbonate (Lexan), acetel monopolymer
(Delrin), acetal copolymer (Acetron GP), POM (acetal), ABS, PEEK, PET, HDPE, LDPE, Nylon (all
grades), Polypropylene, FEP; as cut from a single 12" x 24" sheet up to 0.070" thick.
i. Shattering plastic, such as acrylic, is prohibited.
ii. Plastic may be mechanically altered by cutting, drilling, bending etc. It cannot be
chemically treated, melted or cast. Heating polycarbonate to aid in bending is

My interpretation of the rule is that the 12"X24" is simply a limit on the amount of plastic that may be used within a bot. Not a restriction to using only a single type of plastic. Please provide clarification of this for us."

Your interpretation is correct. Each plastic used must come from the list of allowable materials, and the overall outline of the parts must fit within a 12 by 24 inch rectangle without overlapping.

This question has been answered officially in the past. I’ll look for the official answers.

Might be better place to respond.

I was hoping to get to find an Official Answer to this. Thanks. I know I had received official answers to questions before. I know it was on forums. I guess they moved the official question areas to robotevents or something.

Please don’t believe everything you read on this forum… like anything else you should seek out source documents like this one.

Note the use of the term “cut from a single sheet”. Just as you can’t get two different thicknesses from a single sheet, you can’t get two different materials from a single sheet.

The Q&A is actually pretty easy to search… do make a point of using it lest you get incorrect replies.


In prior years, they have interpreted this to say it must be ABLE to be cut from a single sheet but CAN be cut from multiple. A clarifying QA on Robotevents for the current season would be good.

It sure would have been. I looked for other threads like this at the time, and didn’t find it. Doesn’t mean it wasn’t there, I suppose I just have missed it.