Hello,
I have some questions about how the GDC ruled commercially available hardware last season, and would like to ask the question again for this season.
I’m referencing Change Up Q&A’s because R12 from Change Up is identical to Tipping Point 2.1 except for the addition of 2.5” hardware, and these are the Q&As I would like clarified for this season.
R12 from Tipping Point 2.1
Certain non-VEX screws, nuts, and washers are allowed. Robots may use any commercially available #4, #6, #8, M3, M3.5, or M4 screw up to 2.5” (63.5mm) long (nominal), and any commercially available nut, washer, and / or non-threaded spacer (up to 2.5” (63.5mm) long) to fit these screws.
Under this rule alone, using commercially available hardware regardless of additional functionality would be legal.
The note for R12 goes beyond clarifying, and limits in a way R12 doesn’t hint at.
The intent of the rule is to allow Teams to purchase their own commodity hardware without introducing additional functionality not found in standard VEX equipment. It is up to inspectors to determine whether the non-VEX hardware has introduced additional functionality or not.
The above note is the reason nylon fasteners are ruled legal, and lock washers illegal.
Change Up Nylon Fasteners Q&A https://www.robotevents.com/VRC/2020-2021/QA/747
In general, if the screw could be replaced with a standard VEX screw with no resulting functional changes to the mechanism in question, then they would be legal. However, if the mechanism takes advantage of a functional difference between the two screws (such as the additional flexibility of a nylon vs metal fastener), then they would likely be ruled illegal.
Change Up Lock Washer Q&A https://www.robotevents.com/VRC/2020-2021/QA/732
Standard VEX hardware does not include lock washers; therefore, this would be considered introducing additional functionality, and would not be legal.
Teams use nylon hardware because it is lighter than steel hardware. A team would generally experience a functional difference changing 50 nylon screws to steel screws. But, replacing the nylon screws for VEX thumb screws would most likely not make a functional difference beyond screw head size, but that could be cut.
Nylon screws being used for the flexibility was said to be illegal because that’s not something found in VEX equipment. However, VEX sells plastic thumb screws that would be flexible, making this feature of nylon screws legal as long as it’s the same length as thumb screws.
The keps nuts that VEX sells have “skirts” that can be removed and used as a lock washer, so commercially available lock washers don’t introduce “additional functionality not found in standard VEX equipment” (R12 Note). These were said to be illegal because they aren’t found in “standard VEX hardware” (Lock Washer Q&A), even though the manual doesn’t say they need to be in standard VEX hardware. Lock washers were said to be illegal because they “introduce additional functionality” (Lock Washer Q&A), even though they don’t.
In Tower Takeover, many teams used countersunk screws on their trays to give cubes an easier time sliding. These screws could have been replaced with VEX shoulder screws, but because they don't have an angle to them, it’s not quite the same.
In Change Up it was ruled that nylon standoffs were illegal. Buying a #6 2” spacer from McMaster and tapping it seems to be fully within the rules. This would end up being an almost identical part to a 2” rounded nylon standoff. This could be an additional feature not found in VEX equipment.
Different OD spacers have been used since around 2016, maybe earlier, when 2587 used 5/16 spacers. Different spacers can be used for things like linear slides, or 0.875” aluminum spacers that perfectly fit inside of a c-channel and won’t compress.
This question expands to many different types of commercially available hardware that many teams utilize from sources like McMaster Carr or similar distributors. All of these parts introduce new functionality, some of which are found in VEX equipment, and some of which aren’t. For example, hardware made from different materials (such as aluminum, nylon, fiberglass, steel, titanium, ceramic, and more); washers of different diameter, thickness, or material; RoboSource shoulder screws; different sizes and types of hardware (such as 4-40 screws); and much more all introduce additional functionality.
What specific properties should be considered when determining if commercially available hardware "introduces additional functionality not found in standard VEX equipment"?
Thank you for your time!