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Official Q&A: VEXU 2018-2019: Turning Point

Usage Guidelines All Questions

41: Hardware specified by VEXpro, but not available from VEXpro.


MCCC1
24-Jul-2018

Sorry to be so nitpicky, but there are a couple points on hardware that was not clarified on the June 15th update:

"Answered by Game Design Committee That being said, rivets and hardware found inside of VEXpro kits are considered legal fasteners for VEX U. We will be sure to clarify this in the June 15th update." (emphasis mine).

There are six references to a McMaster Carr part withen the vexpro product specifications, two for master links, three for screws, and one for a washer.

On the page for roller chain: https://www.vexrobotics.com/roller-chain.html "Note: VEXpro does not offer a #35 master link for purchase separately. We recommend McMaster-Carr part number 6261K191 as a suitable replacement. The #25 Roller Chain requires a standard master link. VEXpro does not offer a standard #25 master link. We recommend McMaster-Carr part number 6261K108 as a suitable replacement."

And on the page for the linear gussets:

https://content.vexrobotics.com/vexpro/pdf/217-4399-20180116.PDF "(Note: Some McMaster parts required)" and the BOM lists the following: McMaster P/N 91251A555 1/4-20 x 3.250" Screw
McMaster P/N 91251A553 1/4-20 x 2.750" Screw
McMaster P/N 91251A550 1/4-20 x 2.000" Screw
McMaster P/N 92141A029 9/32" ID x 5/8" OD Washer

Additionally, the versaframe page notes using 5/32 rivets for assembly (https://www.vexrobotics.com/versaframestock.html), but these are not sold by VEXpro, only 1/8 rivets are avaialble.

Do the references to McMaster-Carr parts, and to a 5/32 rivet, make these McMaster-Carr parts legal for VEX-U?

If so, then would the legality of a 1/4-20 x 3.250" screw (McMaster 91251A555) make any shorter screw lengths of 1/4-20 screw legal also (since long screws can obviously be cut shorter). In the same way, VEXpro sells a #10-32 x 2.5 long screw and 10-32 locknut (in kit 217-4824), so would this make #10 screws up to 2.5 long also be legal?

Thank you for your time and consideration.

Answered by Game Design Committee

Sorry to be so nitpicky, but there are a couple points on hardware that was not clarified on the June 15th update.

No apology needed, these types of questions are beneficial to all teams as we work through the nuanced implications of this year's VEX U rules.

Do the references to McMaster-Carr parts, and to a 5/32 rivet, make these McMaster-Carr parts legal for VEX-U?

For the most part, yes.

The #25 master link (6261K108) is legal for this purpose (alongside VEXpro #25 chain).

The following items will be clarified in the August 17th manual update:

  • All rivets up to 1/4" will be legal
  • 1/4-20 screws, washers, and nuts will be legal
  • #10 screws, washers, and nuts will be legal (in addition to the #4, #6, and #8 screws as specified in R7-c)