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

Usage Guidelines All Questions

Bearing Balls


<VUR3> Fabricated Parts may be made using the following processes: a. Adding material, such as 3D printing. b. Removing material, such as cutting, drilling, or machining. c. Bending material, such as sheet metal breaking or thermoforming. d. Casting or molding material, such as injection molding or sand casting. e. Attaching materials to one another, such as welding or chemically bonding (e.g., epoxy).

<VUR4> Fabricated Parts must be made from raw materials. For the purpose of this rule, a “raw material” is any material that would not be considered a “pre-fabricated” part (i.e., has not undergone any of the fabrication techniques listed in <VUR3>).

According to your ruling on Q&A 1235, billets and sheet plastic are considered stock materials although they are cast and rolled. In your ruling on Q&A 1269, a cast gear is considered fabricated and is therefore not a stock material because a billet "is designed to be fabricated into something else," while the gear is "fabricated for the sole purpose of being used as a gear." Adittionally, you stated that if "an item is generally intended to be used in the exact state in which it is sold & purchased, it is unlikely to qualify as a raw material under the VEX U competition rules."

From those rulings and the rules in the game manual, is a ball bearing ball considered a stock material or a prefabricated (therefore illegal). The manufacturing process of a ball bearing ball is as follows:

  1. Wire rod is cut to length. (Although "cutting" is illegal in VUR3a, this should be legal in the same way that it is legal for a long bar of metal billet is cut to individual length. The cutting is not adding complexity, it is shortening the material or detatching it from the spool.)
  2. The cut slug is forged to produce a cold-headed ball. (Some metal billets are forged.)
  3. Flashing removes the "equator" and "poles" giving the ball a rough finish. (Flashing should be legal since it is not a fabrication technique that is listed in VUR3.)
  4. The ball is heat treated (Heat treating is legal according to VUR4.)
  5. The ball is ground to appriximate size. (Grinding could be classified as "removing material," but it is not expressly illegal in VUR3, and metal billet is ground to remove surface defects, so grinding should be legal.)
  6. The ball is polished through a lapping process. (Polishing and lapping should be legal since they are not deemed a fabrication technique in VUR3.)

Additionally, a ball bearing ball is "designed to be fabricated into something else" such as a linear slide, turntable, or gyroscope. It is not usable by itself in the same way a gear is.

With these rules and rulings in mind, is a ball bearing ball legal for use in VEXU?

Answered by committee

Yes, ball bearing balls are legal. This was also clarified in this previous Q&A post: