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Best Building practices (general)

  • bearings

  • screw joints

  • Types of nuts

    • Nylocks are heavier, but have much greater grip. They likely will not significantly loosen even after extensive use. Additionally, not tightening them (and allowing the screw to spin freely) is perfect for rotating joints.
    • Keps are lighter and are the quickest to use. Their teeth help maintain its position when tightened, but not as much as nylocks and cannot be rotated once tightened. Perfect for prototyping or securing less vital structure.
    • Plain nuts are the lightest and are used mostly on parts with places for the nuts designed onto them, such as the clamping shaft collar or V2 rack gears.
  • basic gear ratios

    • Builders can trade motor speed for motor torque (and vice versa) by using a system of gears to change the speed of the output shaft.
    • gears have a set number of teeth, and when gears mesh, the output gear rotates however many teeth the input rotated, not the number of rotations the shaft went through. Builders can use this to their advantage so that the output gear rotates faster, but with less torque (larger gear → smaller gear), or slower but with increased torque (smaller gear → larger gear).
    • If gear sizes become too extreme, more advanced builders may use compound gearing to exponentially modify their gear ratios. This is done by having the output shaft from previous gearing become the input shaft for more gearing with different gear sizes.
  • no cantilevered drive wheels

    • As a general rule, for anything on a shaft other than shaft collars and washers, the shaft should be secured to structure on both sides of whatever it is supporting.
    • Not doing this results in the shaft having a lot of wiggle room, as typically seen when wheels are exposed on the outside of a robot.
  • spacers, standoffs mounting

  • use all omni drive base with 4 motors

DR4B Tutorial by 333A

VEX Build Quality Tutorial/Instruction video:

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