Is there a limit on rubber band sizes?

[ALCArobotics]

Today my team was thinking of a fix a problem, but we ran into the problem of rubber bands. We need one that is slightly bigger and smaller than what we have. I thought this was no big deal because we could just grab other rubber bands that will fit correctly, but out teacher said that there is a limit on the sizes of rubber bands. Is this true?

[RandomKidOnAVexTeam]

The rubber bands have to be functionally the same as the Vex ones. Although I’ve only seen one team get flagged on it and it was because their bands were huge, it is still illegal. I don’t remember what the actual size is, but there is a requirement.

[holbrook]

Hi @ALCArobotics, welcome to the VEX Forum!

Any question that asks “is it legal” should be answered by consulting the game manual. In this case the relevant rule is <R6d>:

<R6> Robots are built from the VEX V5 or Cortex system. Robots may be built ONLY using official VEX V5 and Cortex 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 documentation.

…

d. Any parts which are identical to legal VEX parts are permitted. For the purposes of this rule, products which are identical in all ways except for color are permissible. It is up to inspectors to determine whether a component is “identical” to an official VEX component.

(emphasis mine)

So, you can only use rubber bands if they are:

1. Purchased from VEX as part of the EDR/V5 product line, or
2. The same size as rubber bands that VEX sells as part of the V5/EDR product line.

(can you use rubber bands made from different materials? see this thread)

The question is then, which sizes of rubber band does VEX sell as part of the V5/EDR product line? Looking at this page, we see that “VEX-brand rubber bands” are only available in #32 and #64 sizes; thus, those are the only sizes legal for use in VRC.