Robotics Education & Competition Foundation
Inspiring students, one robot at a time.

This Q&A is Read Only.

Official Q&A: VRC 2023-2024: Over Under

Usage Guidelines All Questions

217-6626, 217-6627 Polycarbonate sheet and R18

Charles Jeffries (Event Partner)

<R6> states:

Robots are built from the VEX V5 system. Robots may be built ONLY using official VEX V5 components, unless otherwise specifically noted within these rules.Teams are responsible for providing documentation proving a part’s legality in the event of a question. Examples of documentation include receipts, part numbers, official VEX websites, or other printed evidence.

<R18> states:

A limited amount of custom plastic is allowed. Robots may use custom-made parts cut from certain types of non-shattering plastic. It must be possible to have cut all of the plastic parts on the Robot from a single 12” x 24” sheet, up to 0.070” thick.

a. The intent of the area/thickness constraints is to limit the number of custom plastic parts used in Robot construction, not to define an absolute volume. For example, using a sheet which is 0.035” thick does not permit two 12” x 24” sheets’ worth of parts. b. Plastic parts do not have to be literally cut from the same original 12” x 24” sheet. However, all individual parts must be able to “nest” or rearrange into a 12” x 24” area.

i. A collection of parts which theoretically have a total surface area of 288 in2, but cannot be nested onto a single 12” x 24” sheet, would not be legal. See Figure 36.

c. 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 acceptable.

d. Legal plastic types include polycarbonate (Lexan), acetal monopolymer (Delrin), acetal copolymer (Acetron GP), POM (acetal), ABS, PEEK, PET, HDPE, LDPE, Nylon (all grades), Polypropylene, and FEP.

e. Shattering plastic, such as PMMA (also called Plexiglass, Acrylic, or Perspex), is prohibited.

f. The PET Sheet Variety Pack (276-8340), sold by VEX, is considered “plastic” in the context of this rule, and is subject to the same limitations as “off-the-shelf” plastic sheets.

g. This rule does not apply to 3D printed plastic parts. 3D printed parts are not permitted in the VEX Robotics Competition, except as non-functional decorations (per <R8>) or as custom License Plates (per <R9>).

The '1/32" Gray Tinted Polycarbonate Sheet (36" x 72")', VEX part number 217-6626 is legal under R6, as well as its sibling 217-6627. However, there is no clause under R18 which restricts the maximum portion of this sheet which can be used. Therefore, there is some confusion over whether 217-6626 allows for "bypassing" the plastic limit. This is likely the result of an oversight in R18f, which provides such a restriction for a similar vex product, 276-8340. If a similar clause were added for 217-6626 and 217-6627, then this would prevent this confusion and/or inconsistency.

Thank you.

Answered by committee

As a reminder, per the Q&A Usage Guidelines "The Q&A system is for rules clarifications only". For game questions, suggestions, or concerns outside of specific and official rules questions, feel free to contact [email protected].

With that being said, we appreciate this suggestion, and will be sure to include this clarification in a future Game Manual update.

In the meantime, to be clear - the polycarbonate sheets sold by VEX (217-6626 and 217-6627) are considered "plastic" in the context of <R18>, and are subject to the same limitations as “off-the-shelf” plastic sheets.