Modular Marble Run

Hello everyone,

This is a modular marble run I created using tinkercad after seeing a similar one somewhere on the internet.. I thought I can make one myself using a 3d printer..
I design the cube to be the main structure to hold on to the tracks so you can make whatever design you’d like..

i use 5mm magnetic balls that is inserted into the cube frames to help snap the cubes together when assembling any design for the tracks..

you could also use clips i design to hold the cubes together if you dont want to use the magnetic balls

The marble run currently only have 4 tracks.. slope.. straight.. turn.. and u-turn.. I’ll be updating more tracks later on..

Difficulty Level:

  • 3D printing – Easy
  • Assembly – Easy
  • Wiring – Easy
  • Painting – Dont have too if you dont want too


  • marbles – 16mm diameter marbles.. u can also use ball bearings of the same size to give it an extra speed due to weight
  • superglue – a lot of glue.. cause you’re gonna need to make a lot of this cubes
  • 5mm magnetic balls – its optional and you gonna need a lot of it too..

3D printing files:

The first thing i needed to model was the cube.. i made the design repetitive so that you only need to print one frame 4 times to assemble into a cube.. i also made notches on the middle of the cube frame to help hold the tracks in the middle and can snap on the clip if needed.

The frame have 2 holes on each side to insert 5mm magnetic balls in them.. using magnetic balls in the cubes give it a snapping together for easy design and building your tracks.. i learn the magnetic balls trick from making a lot of dungeon tiles which also have magnetic balls in them for easy snap together.

By using magnetic balls.. your magnet polar is free to rotate any direction and when assemble together with other cubes.. it wont have restriction in +ve or -ve polar that may repel the cubes rather than snapping it together..

Using tinkercad.. i also model different tracks by making a standard size and location of each tracks.. once i got the measurement of each tracks i had to export the tracks into another 3d software to smooth out the tracks..

Corner turn track was the hardest to get right since the track needs to be tilted so that the marble wont run out of the track..

Assembly – Cube

The assembly of the cube is quite straight forward since there is only one model and it needs to be 3d printed a lot..

If you’re thinking of inserting a magnetic ball inside the frame of the cube.. you will need to insert one magnetic ball inside and one outside of the frame is to hold the balls so they dont fall off when you’re trying to glue it together or so that the balls wont touch the frame that has glue on it.

Have a look at the video on the trick i used to insert the balls into the frame and glueing it together..

Assembly – marble tracks

So there are 4 tracks currently that i have modelled:

  1. straight
  2. slope down
  3. corner turn
  4. u-turn

straight only uses 1 cube but i also made a longer version that uses 2 cubes.. 3 is kinda far fetch since the marble will run out of momentum if its too long..

slope down uses 3 cubes and is a bit tricky to asemble.. the main body of the slope needs to snap into one of the cube.. using clips to hold the cubes together is good idea so it wont break apart..

corner turn also uses 3 cubes.. depending on your printer the edge of each track sometimes lift a bit and wont align with other tracks.. my solution would be to glue the edge of the track to the cubes..

u-turn uses 2 cubes only and fairly straight forward asembly


Its really fun to create the tracks and have the marble go through it.. using a ball bearing makes the run a lot faster and it requires different track design since its heavier and have more momentum when going down the tracks.

Currently i’m also working on a spiral lift so that the marble run would loop on the tracks.. its gonna use a SG90 servo motor and 3 AA battery that will fit into one cube..

As you can see in the top video.. i had my nephews test play the marble run and they had a blast making the tracks and think of ways to make it look cooler.. they also turn the cubes into a tower competition to see who can make the highest tower..

future plans.. add more different tracks..

Have fun making the modular marble run and happy 3d printing..

Future expension

if you like the project.. please consider donating to us so we can make more awesome project like this in the future

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