Re The legality of lathing high strengthen shaft

VEX V5 Technical Support
1

As per R22

Most modifications and repairs to non-electrical components are allowed. Physical modifications such as bending or cutting are permitted and may be done to legal VEX Robotics Competition
metal structure or plastic components.
a. Physical modifications to electrical components such as a legal microcontroller or radio is
prohibited unless otherwise explicitly permitted, per .
b. Internal or external mechanical repairs of VEX Limit and Bumper switches are permitted. Modifying the metal arm on the Limit Switch is permitted. Using components from these devices in
other applications is prohibited.
c. Metallurgical modifications that change fundamental material properties, such as heat treating,
are not permitted.
d. Teams may cut pneumatic tubing to a desired length.
e. Teams are permitted to fuse/melt the end of the 1/8” nylon rope to prevent fraying.
f. Welding, soldering, brazing, gluing, or attaching in any way that is not provided within the VEX
EDR platform is NOT permitted.
g. Mechanical fasteners may be secured using Loctite or a similar thread-locking product. This may
ONLY be used for securing hardware, such as screws and nuts.

It seems it might be legal to lathe high strength shafts like shown in the

WIN_20190716_21_59_27_Pro
WIN_20190716_21_59_27_Pro1600Ă—1200 502 KB

is this legal?

Edit: To clarify, We are creating lead screws from high strength shaft.

WIN_20190717_15_16_22_Pro
WIN_20190717_15_16_22_Pro1280Ă—720 146 KB

6 Likes
2

This is most likely legal, but you should ask in the official Q&A if you want a guarantee. I know i’ve done similar things (such as putting a part in a drill and spinning it against a file as a makeshift lathe) and many competitors (before vex began selling 3/8" OD spacers) have been using <0.5" OD nylon spacers because in theory the spacers can be turned down to those diameters.
Additionally, a couple suggestions since you’re down to lathe parts:

  • Shoulder screws (it is very very difficult to find shoulder screws with the right shoulder diameter (0.176") and making them yourself sounds really cool
  • lower friction, circular and/or keyed shafts with threaded ends to serve as alternatives to 2" screws for both screw joints and long fasteners
3

No need for the official Q&A. It’s perfectly legal to use a lathe for turning parts from official vex material. You may want to have a picture or two of the process to show at inspection that you turned them yourself.

6 Likes
4

Oh thanks good thanks for clarifying