How to Make Lego Technic Compatible Parts in Fusion 360




Introduction: How to Make Lego Technic Compatible Parts in Fusion 360

Attending high school: Homeschool

Whether you are looking for a discontinued Lego part, or want to make a custom Lego part, this tutorial will help. I have used Fusion 360 to do both. This tutorial will focus on Lego Technic parts.

My example will include making a Lego mount for a brushless motor and a servo mount. I used these to make a high powered Lego RC car.


Step 1: Measurements

If you want to use 3D printing to adapt non Lego parts into your Lego design, its a good idea to start by measuring the non Lego part that you want to use. A digital caliper makes this process easier.

Step 2: Build Your Adapter or Lego Part

If you are creating an adapter to a non Lego part, it often works best to create the non Lego side first.

Step 3: Make Your Part Lego Compatible

At this point, you may place your adapter into an existing Lego part (example of the motor mount), or add peg holes or pegs. Lego studs are 8x8x8mm peg holes are around 5mm depending on the precision of your 3D printer. Distance center to center between peg holes should be divisible by 8. Dividing by 8 will give you the length in studs.

You can find Lego STL files on as well as a few other sites.

Step 4: Set Up Your Part for Printing

Import your Lego compatible part into your 3D printing utility and set up for printing. I find that PrusaSlicer works better than many other slicers. Depending on the part I use %60 - %100 infill. Add supports and adhesion if needed and send to your printer!

Step 5: Print Your Part

Step 6: Post Process

Remove any supports and file down anything that needs it. Often I need to drill the peg holes.

Step 7: Install Your Part and Have Fun!

I installed my Lego parts into a Lego RC car. So far they have held up! My Lego car is much more powerful now with the brushless motor instead of the Lego motors I used to make cars with. Its also easier to steer now that I have a servo to steer my car with.

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    5 months ago

    Sweet Cad!


    5 months ago

    Very nice! : )