Build a LEGO PinchBot that pinches and picks small objects using gears, levers, and rubber bands, learning about simple machines and problem-solving.



Step-by-step guide to make a LEGO PinchBot
How to Program a LEGO Robot: Step-by-Step Guide for Beginners!
Step 1
Gather all the LEGO pieces gears rubber bands and small objects you will use and put them on your workspace.
Step 2
Build a sturdy rectangular base by snapping plates and bricks together so it will hold your PinchBot steady.
Step 3
Build two vertical supports on the base and place them about four to six studs apart where the claw will sit.
Step 4
Slide a long axle through the two supports so it can spin freely left to right.
Step 5
Attach one lever beam to the axle on one side and attach a second lever beam to the axle on the opposite side so the two beams act as the two halves of a claw.
Step 6
Hook a rubber band between the outer ends of the two claw beams so the rubber band pulls the beams together to make a pinch.
Step 7
Fix a small gear onto the claw axle so the gear turns whenever the claw axle turns.
Step 8
Build a crank axle behind the supports and add a larger gear and a small handle or wheel to the crank axle.
Step 9
Position the crank gear so it meshes with the claw gear and make sure turning the crank makes the claw axle rotate.
Step 10
Turn the crank to open the claw place a small object between the claw ends then release so the rubber band closes the claw and lifts the object.
Step 11
If the grip is too weak move the rubber band one stud closer to the claw tips to increase the pinch strength.
Step 12
Take a photo or short description of your finished PinchBot and share it on DIY.org
Final steps
You're almost there! Complete all the steps, bring your creation to life, post it, and conquer the challenge!


Help!?
What can we use if we don't have the exact LEGO gears, axles, or rubber bands listed?
If you can't find the specified small gear, larger crank gear, or Technic axle, substitute any similar-sized Technic gears or a 2x2 turntable plate for the gear, a long Technic axle or a wooden skewer through the supports, and small hair elastics in place of the rubber band hooked between the claw beams.
The crank turns but the claw doesn't move — what should we check?
Check that the crank gear is positioned so it meshes with the claw gear and that the claw axle spins freely through the vertical supports (loosen tight bricks or re-seat the axle) so turning the crank rotates the claw axle as instructed.
How can we adapt the build for younger or older children?
For younger builders, pre-build the sturdy rectangular base, vertical supports, and crank axle and let them attach the claw beams and rubber band, while older kids can swap lever beams for longer liftarms and add extra gears to experiment with gear ratios and lift heavier objects.
How can we improve or personalize our PinchBot after it's working?
Add a second larger gear to change speed and torque, move the rubber band one stud closer to the claw tips to increase pinch strength as suggested, swap in different lever beams for new claw shapes, and decorate the base with colored plates before taking a photo for DIY.org.
Watch videos on how to make a LEGO PinchBot
【Tutorial】How to build Lego Robotic Hand with Spike Prime
Facts about simple machines and mechanical engineering
🧱 The Lego Group produces tens of billions of LEGO bricks every year — that's a lot of building power!
⚙️ Gears can trade speed for force: a small gear driving a larger gear increases torque but slows rotation.
📐 Levers are one of the six classic simple machines and have been used since ancient times to move heavy objects.
🪢 A rubber band stores elastic energy like a tiny spring — stretch it and that energy can power movement when released.
🤖 Programs like FIRST LEGO League use LEGO parts and simple machines to teach kids real-world engineering and problem-solving.


DIY is a creative community where kids draw, build, explore ideas, and share.
No credit card required