Low-Cost Claw Machine

This low-cost claw machine is made out of Lego power functions and Lego Technic elements. It is a great mini arcade game for DIYers and makers.

The picture is just a small scale version without the motors.

Step 1: Materials

3-Lego Power Functions M-motors

1-Lego Power Functions Battery Box

2-Lego Power Functions IR Transmitter

2-Lego Power Functions Receiver

Lego Technic Tread Links

6-AA Batteries

Lego pieces in instructions


Lego Digital Designer

Step 2: Building Instructions

I used Lego Digital Designer to make the instructions, the instructions are for the base and the claw.

Use pages 18-24 in the PDF

The wiring in the LDD file is for testing purposes only, you will have to reconfigure the wiring later.

Step 3: Claw

There are a few modifications you need to make to the claw in order for it to function with a motor.

  • Remove the gears, axle, and bush from the claw at the top
  • Attach a 2 way connector for the axles
  • Attach an axle long enough
  • that it can fit in a power functions motor

Step 4: Dropping Mechanism

Tape a piece of string to the axle in the top motor. Wrap the string around the motor and connect the other end to the claw.

Make sure the string is long enough so that the claw can touch the bottom of the base.

Step 5: Connecting the Wires

Put batteries into the battery box

  1. Attach both the transmitter wires to the battery box
  2. Attach 2 motor wires to one transmitter, and 1 motor wire to the remaining transmitter
  3. Set both frequencies (on the transmitter and receiver) to 3
  4. You should now have control of your motors

The picture shows some of the connections.

Step 6: Controls

Your controls might be different based on the connections

Step 7: Additions

Your claw machine should be up and running. You can add additions to your claw machine like this one:

Happy Building!



    • Build a Tool Contest

      Build a Tool Contest
    • Remix Contest

      Remix Contest
    • Organization Contest

      Organization Contest



    Question 4 months ago

    Any chance of redoing this for the EV3 system?