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Official Q&A: VRC 2022-2023: Spin Up

Usage Guidelines All Questions

Legal String Modifications and Sizes

67101C
2-Nov-2022

Rule R7 reads

An unlimited amount of rope / string, with a thickness / diameter between 1/8” (3.175mm) and 1/4”(6.35mm).

Rule R11 reads

All specific dimensions listed in this rule are intended to be ‘nominal’ references

Rule R22 reads

Physical modifications, such as bending or cutting, of legal metal structure or plastic components are permitted. d. Fusing / melting the end of legal nylon rope / string (see <R7e>) to prevent fraying is permitted.

  1. How is the diameter of string measured? Would this ribbon be legal to use?

  2. Is it a legal physical modification to unbraid legal string in order to make it thinner that the legal diameter as this is all that some manufactures do before selling the string? If the answer is that it must be sold by a manufacturer pre-braided, what constitutes a manufacturer? (ex. would someone selling homemade string count manufacturer?)

  3. Is it legal to braid together thinner than legal string so that a strand is a legal diameter?

  4. Are string sizes nominal references as with screw sizes? (ex. 1/8" string is bought yet is becomes stretched through use and measures 0.12 inches when sized, but the team can provide proof they bought legal string)

  5. Is it legal to use string less than 1/8" in diameter for purposes other than covering tiles for the endgame?

Robot Rules and Inspection  
Answered by committee

The answer to question #2 in this post has been revised slightly to differentiate between "braided string" and "manufactured multi-strand string."

We'll start by pointing out that the red box note you've quoted from rule <R11> only applies to fasteners. The dimensions listed for the minimum and maximum sizes of string are not nominal. The only measurement of string that matters in Spin Up is the actual diameter when measured across the narrowest point of the string; package labels in some cases may be accurate, but for others the actual measurement will differ wildly from the nominal measurement (e.g., hand-spun fibers like yarn). It is the Team's responsibility to determine the actual size of the string that is in use on the Robot.

  1. How is the diameter of string measured? Would this ribbon be legal to use?

This question was asked and answered in Q&A 1271. String must measure between 1/8"/3mm & 1/4" in every dimension but length.

  1. Is it a legal physical modification to unbraid legal string in order to make it thinner that the legal diameter ...?

Deconstructing manufactured multi-strand string is permissible, as long as the resulting thinner string used on the Robot has a minimum diameter of 1/8"/3mm. For example, deconstructing a legal 1/8" string to create smaller strings will result in multiple illegal strings that cannot be used on VRC Robots.

  1. Is it legal to braid together thinner than legal string so that a strand is a legal diameter?

This would only be legal if each of the thinner strings also had a minimum diameter of 1/8"/3mm before being braided, and if the final braid is not wider than 1/4" in any direction.

  1. Are string sizes nominal references as with screw sizes?

No. However, it has come to our attention that the standard metric equivalent of 1/8" string is 3mm rather than the 3.175mm specified in the November 1 Game Manual update. The next Game Manual update will be updated to indicate that the minimum dimension of string is 1/8" / 3mm.

  1. Is it legal to use string less than 1/8" in diameter for purposes other than covering tiles for the endgame?

No. As specified in rule <R7e> and clarified here and in Q&A 1271, only string with a minimum diameter between 1/8"/3mm and 1/4" is permitted for use on the Robot.