Key Ideas for Building with VEX GO

VEXcode GO Screen

VEX GO is a fun and educational system intended for use with students in grades three through five. It's flexibility and function can also be utilized with many higher grade levels.

This article will introduce you to some key ideas which will help students use the VEX GO system.


Here are the basics to building, which hold true in almost everything VEX related, as well as the real world too.


Try for yourself, as well as ask your students, to find a piece shown in the poster and orient it in the same manner in your hand as shown. Learning to do this while building ensures that pieces are getting connected in the correct locations, as well as it enhances your spatial reasoning for future builds. Being able to visualize a part in a “glass box” is a huge concept in engineering as it depends on the image you are creating in your mind. VEX Build Instructions are created with these views in mind, so challenge yourself and reorient the part in your hand to see the best optimal view when creating your robot.

Part Categories

VEX Robotics uses three main categories of parts. Starting off in the STEM Lab, guided instructions are used to facilitate your spatial reasoning before you take on free-building, or building without guided instructions for the purpose of fitting your needs. All you need to remember at this point is that any build you can imagine is absolutely possible, as it simply consists of a certain order of these categories. Try rearranging this order in the future, and you are now free-building like the pros!

  • Structure: used to fasten parts together, and contain the overall shape of the build
  • Motion: used to get the robot to move. Includes shafts, gears, pulleys, wheels, racks and slides
  • Electronics: the brains of the build. Includes sensors, motors and the brain

Can you and your students determine what parts belong to each category?


Building with VEX GO is designed with simplicity in mind. Connecting pieces should be thought of as connecting your phone to a charger. You do not have to apply exorbitant amounts of pressure, but you cannot just whimsically rest it on another part. Try this yourself! Use a pin and connect it to any beam. You should be able to feel or hear a distinct click when the part becomes fully inserted. Not fully connecting pieces together may result in structural failure at a later point, something engineers try to avoid.

Circles vs. squares - a connection for motion

The VEX GO building system consists of plastic parts, metal shafts, and electronics.

The plastic parts may have:

Gray Pin

Square Pegs

Green gear

Square Holes

Red pin

Round Pegs

Blue connector

Round Holes

Red axle

The metal shafts are square rods.

These different shapes have very specific functions for the VEX GO system.

Square peg/shaft in a square hole

motor peg

When a square peg/shaft is placed in a square hole and the peg/shaft is forced to spin, the part with the square hole will be forced to spin. For example, if a square pin is placed in the square hole of a motor, the pin can be forced to spin.

motor gear

If the square hole of a Green Gear is inserted on a spinning, square Gray Pin, the gear will also be forced to spin.

Parts with square pegs or square shafts

  • Gray Pin
  • Red Shaft
  • Green Shaft
  • Capped Shaft
  • Plain Shaft

Parts with a square hole

  • Motor
  • Knob
  • Gray Wheel
  • Red Gear
  • Green Gear
  • Blue Gear
  • Green Pulley
  • Orange Pulley
  • Red Square Beam
  • Thin Beam

Round peg in a round hole

Connecting pins to beam

When a round peg is placed in a round hole of a part, the part can spin freely on the round peg. For example, if a round peg of a Red Pin is placed in the round hole of a Black Beam, then the beam can spin freely on the Red Pin.

Can't insert

Note: Round pegs will not fit into square holes.

Square peg or shaft in a round hole


When a square peg or shaft is placed in a round hole of a part, the part will be able to spin freely around the square peg or shaft. For example, if a Plain Shaft is inserted through the round hole of a Blue Wheel, then the Blue Wheel can freely spin on the shaft.

Two or more connections


Connect two parts together with one pin, and exert a force on one. What happens? As you can see, the beam is able to move freely about the pin that you connected, to stop this, see next step.

Conecting plates

If two parts have two or more connectors connecting them, they will not spin. For example, if a Yellow Large Beam has two Red Pins inserted in its holes and a Blue Large Beam is inserted onto the Red Pins, then the Yellow Large Beam and the Blue Large Beam will be solidly connected together.

Caps, flanges, and shaft collars

The VEX GO Kit’s pins and shafts have special features called caps or flanges.


Inserting caps

Caps are features which are found on Pink Pins and Capped Shafts which stop the parts from passing completely through the hole of the part they are inserted into.


The Pink Pin as well as the Capped Shaft is beneficial as it does not have a flange, allowing for usage of gears with tight constraints. This usage is utilized on the Code Base.



Flanges are features found on pins and shafts which stop them from being inserted further than one part thickness into a hole.


This is utilized on the Code Base and is beneficial as the flange prevents the shaft from slipping through the beam, at the same time receiving power from the motor.

Shaft collars

Shaft collar

Shaft collars are rubber collars which can be put onto metal shafts.

Securing a shaft

A Shaft Collar can keep a metal shaft from sliding through the hole of another part. For example, a Shaft Collar can keep a Red Shaft from sliding back out of a round hole in a Black Large Beam.

Securing a wheel with a shaft collar

A Shaft Collar can keep a part from sliding off of a Shaft. For example, a Shaft Collar can keep a Gray Wheel from sliding off a Shaft.

Colors and sizes


Another feature which makes the VEX GO such an easy building system is the parts have their own unique color. These colors help match the parts to the steps in the build instructions.

For example, a Blue Connector and a Yellow Connector may look similar. However, when the build instructions call for a Yellow Connector, there is no doubt which connector should be used.


In addition to helping identify parts that are needed for a step in the build instructions, parts of the same color will be the same size. For example Yellow Beams are always smaller than Blue Beams.


This feature where a part size can be identified by its color helps a great deal when matching up parts. For example, you will know both sides of your assembly are the same size if you use a Dark Gray Large Beam for each side.

The shapes of the parts and their colors allow you to easily build many different things with the VEX GO system.

For more information, help, and tips, check out the many resources at VEX Professional Development Plus

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