CVJ (Constant Velocity Joint) Fidget Toy

This Birfield-type Constant Velocity Joint is very addictive to fiddle with.Although it requires two hands to operate it turns pleasantly smoothly, while it will transmit a surprising large amount of torque over a large angle, up to 45° for the single CVJ version, twice that for the double CVJ coupler.I've added some knurling on the shafts to add grippiness for easier handling. Interestingly, I've used exactly these type of CVJ's in my RC-car that I designed and built some years