Plastic limit

Recently at a competition my team, and I attend during inspection some inspectors were saying that teams were not allowed more than one material per robot as per R10. According to R10 in the tipping point Manuel “ may use non-shattering plastic … as cut from a single 12” x 24” sheet up to 0.070” thick.”. My question is if you are allowed to use sheets of different materials as long as it fits in a 12x24 sheet, or put simply is the rule meant to limit both material type, and create a limit of material, or just to create a limit. There are older forum post from almost 3 years ago saying that it’s just to limit material, however I am not sure if it still applies. If it is a limit to material where can I find a trusted source to verify this interpretation of the rule?


Maybe you could ask the GDC themselves?


Easy - only trusted source is to ask on the Official Q&A.

and to answer your other question:

There are older forum post from almost 3 years ago saying that it’s just to limit material, however I am not sure if it still applies

Information from previous seasons about rules that have been answered on this forum either officially or unofficially do not really carry forward to current season as the game context changes a lot. This was the topic of a Q&A a while back and still applies. Clarifications to rules should be made each season.


While previous years’ Q&A rulings do not carry forward, I’ve generally used this response from Karthik when inspecting robots:

You can use multiple physical sheets for convenience, however all parts must be able to be reassembled into a single 12" x 24" sheet.

As @Arthur5150D notes, the controlling language is: as cut from a single 12x24 inch sheet where the word “as” is doing a lot of work. This phrasing seemingly allows for teams whose non-shattering plastic fails/break/needs to be replaced can be done so without replacing all other non-shattering plastic on the robot from a brand new 12x24 inch sheet. It also, seemingly, allows for teams to mix-and-match legal materials, so long as all non-shattering plastics could be re-assembled back into a single 12"x24" sheet (of mixed material).


I mean, theoretically you could obtain a single sheet of plastic that happens to have been made from different legal materials in different sections just so that you could cut it up perfectly how you want it.

and the rules don’t say your plastic doesn’t need to actually come from this theoretical sheet, it just needs to have been possible to do so.


That’s the logic I’d use to argue for material use during inspection if it doesn’t get explicitly answered in the Q & A. Also realize, there’s no way to really enforce this rule one way or another. Not every team CADs and provides documentation. It really is an honor code system.


I did have this debate recently with another coach at a scrimmage earlier this year. One of my teams’ uses components that are a mix of solid-black ABS and clear-ish Lexan, so it is obvious the non-shattering plastics on the robot are not cut from the same sheet of material. We came to the conclusion that the post from 2015 still seems to hold, given that the language has not changed.


Do note that the guidance of not following previous season’s Q&A guidance comes when Karthik left the GDC. I had asked a specific Q&A question about previous guidance and the clarification was that the game context continually changes.

As for single material, I would tend to lean towards expecting GDC clarification towards a single material property in “pre-covid” times - this year, who knows. Hence why it is important to ask this of Q&A for this season. Level playing field mindset would favor the single material because typical teams would buy a single material from their local stores. However, definition of “rope” this year is quite broad.

Long winded, ask the Q&A for clarification if events are interpreting it differently from competition to competition.


Hey 5150d! This is team 228a from that same comp you guys went to. We had the same issue, using clear lexan and then a backplate from one of the change up goals. We ended up being told by some ref, I forget who it was, that it was legal under some q&a ruling. We didn’t even have any issues at worlds last year doing this same thing.

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At the same time, I think there is a reasonable expectation that if the wording in the manual hasn’t changed, then previous rulings should be assumed hold true unless the GDC says otherwise. This is the only way we avoid 20+ Q&As at the beginning of the season asking if previous ruling still apply, which would waste everyone’s time. If the GDC intends for the meaning of the rule to change, then they are free to change the wording of the rule.


Cheapo over here.

Is Construction paper allowed?

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Any questions about legality can be answered by the Game Manual !

In this case, you will want to take a look at R6. The other robot rules may also be relevant.


This discussion got me thinking:

Technically, couldn’t you technically use 2 12" x 24" sheets worth of material if each was thinner than 0.035"? You could assemble all those pieces worth of material into a single 12" x 24" sheet 0.070" thick by stacking the material in 2 layers. In theory, you could even say that they were from a single 0.070" thick sheet that you just somehow managed to cut into 2 0.035" sheets…

I couldn’t find anywhere in the game manual that said this would be illegal…but I may have missed something



Not permitted per old Q&A, but wouldn’t anticipate any changes if asked again…


Again, while prior years’ Q&A do not carry forward, this post from Karthik seems to apply:

Different thickness may be used up 0.070", provided that the total area does not exceed that of a single 12" x 24" sheet. This is very different than being restricted to a total volume of 12" x 24" x 0.070" = 20.16 in^3.


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