Introduction: Create Your Own LEGO® Kit From 3D Model Files

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There are quite a few standard LEGO® sets. However, this number is dwarfed compared to the millions of 3D models that you can create or download from the web. In this short tutorial we show you how to generate a layer-by-layer build plan from any 3D model using your standard LEGO bricks with just a few clicks.

Step 1: What You Need and Background Information

You need:

  • A suitable 3D model file
  • A Windows/Mac/Unix Computer with a Chrome/Firefox/Safari browser
  • An internet connection

What is a 3D model file, and where to get them?

If you ever saw a 3D printed object, played a modern video game, looked at Google Earth, used a GPS, or saw one of the great animated movies from Pixar, Dreamworks, Disney or other studios, you have been in close contact with 3D model files. Vastly simplified a 3D model is a scalable “picture” of an item you can “fly around” and look at from any perspective you wish.

Because of the broad application of 3D models, they come in different shapes and colors. Some are widely available and free, others are scarce and you might need to pay for. The most common 3D model file formats are:


STL files are widely used for 3D printing and do not contain color information. Since the VAST majority of today’s household 3D printers are single colored, this is not a significant 3D printing limitation.

While being single-colored it is a disadvantage for the creation of LEGO plans, STL files are in WIDE circulation and most of them are absolutely FREE for personal use.

You could “colorize” STLs for LEGO plans by importing your STL into a Minecraft world with and “reshape” and “repaint” it in Minecraft before creating the plan for your LEGO bricks. Or just wait for the release of BlockPaint3D …


DXF files are usually exported from CAD programs such as AutoCAD. For that reason you will find technical designs or houses in this format. Like STL files, they contain no color information.


The filmbox format was originally used for capturing motions for animated movies. It is widely used for color 3D models today, as it allows to carry the color information WITHIN the model file and does not have to rely on external material or pattern files (such as OBJ) that makes it harder to handle.


Is a simple geometry format that allows storing color/material information in separated files that can then be referenced. It is mostly used for color models, but there are only a very limited amount of quality OBJ files available for download. Because every model consists of multiple files (the OBJ file, the MTL file (containing the references to the material files) and any number of material files, it is harder to manage/handle).


PLY is a very versatile file format that stores point clouds as well as triangular models. It can handle color as well as monochrome. Very much like OBJ, quality color objects are rare and if anything goes wrong, it is pretty hard to debug due to the versatility of PLYs formats.

Where can I get great 3D models to create build plans for my LEGO bricks?

It is always a good start to google for <desired object> stl free download fbx and follow the results.

Apart from that, some great sites to get 3D models for your LEGO bricks are:

I have the right 3D file but the wrong format. Can I convert one format into the other?

Yes, you can. There are some great free converters such as:

Step 2: 1-2-3 With BRICKPLICATOR to Convert Your 3D Model Into Custom LEGO Instructions for Your Standard LEGO Bricks

Let us say that we would like to build the White House with our LEGO bricks. Our search on Google gets us several results.

Lets say we choose a 3D model file from (see picture).

After unzipping the STL file, go to to convert your 3D model into custom LEGO instructions for your standard LEGO bricks.

Select the Get Started button on the right side of the screen,....

Brickplicator STEP 1

.... click Browse to select the 3D model file you want to turn into a build plan for your LEGO bricks.

Select the 3D file you just downloaded and hit Upload.

Brickplicator STEP 2

As a next step you can decide on the size and the Y/Z rotation of the 3D model.

Alternative or Standard Rotation?

Since our view on the build plate is “top-down”, the upper “Standard Rotation” option would put the Empire State Building on its side on our build plate. The lower “Alternate Rotation” would place it bottom-to-top, which is what we want.

Since 3D models follow no standard when it comes to using an XYZ or an XZY axis, this option allows you to swap the Y and Z axis to make sure you can use all 3D models regardless of their axis rotation.

Solid or Hollow?

Some STL 3D models have all the details of the inner details of the object and some are solid. If you run into a solid object, you might want to create a hollow model for your LEGO bricks to save bricks and to build the inner details yourself. In this case select the Create outer shell only option.

What is LXF and the LEGO® Digital Designer (LDD)?

A LXF file is a three-dimensional model or scene created by LEGO® Digital Designer (LDD). It can be loaded and refined by LDD. The LDD allows you to refine your model and use non-standard LEGO bricks to enhance the model generated by Brickplicator.

Brickplicator STEP 3

To receive the build plan for your LEGO bricks via eMail you need to insert your eMail address into the appropriate field and hit the Submit button.

Since it takes some pretty hefty computing to generate your custom LEGO brick set, it might take up to 30 minutes for the model to arrive in your inbox. If your model has more than 130 layers and is higher than 1 meter – yes we have tried that - it might even take longer.

Step 3: The EMail Containing Your Custom LEGO® Building Instructions

Once the eMail shows up you can go to your personal MOC of the White House for your LEGO bricks.

Once clicked on the Go To Build Plan button, it takes you to a page containing a 4 layer preview of your LEGO layer-by-layer brick build plan. If you selected a model small enough to qualify for FREE delivery, you can select the GET YOUR FULL PLAN FOR FREE button at the top of the page to get to the full build plan for all layers.

If you happen to own all LEGO bricks you need, you are all set for your custom LEGO White House adventure.

For all of you that are missing a few or all of the required LEGOs, the system has generated a (completely optional) Brick Owl shopping basket for convenience.

Brick Owl provides a worldwide marketplace service to allow customers to connect with stores selling LEGO and LEGO related items. These stores independently market, sell and support these items.

Every layer shows two sides. The left view shows your progress and the right top-down shows you where to put the bricks. Stud-by-stud. The previous layer is shown a reference with dimmed gray bricks.

Step 4: Optional: Can I Refine the Model With the LEGO Digital Designer or Other LXF Compatible Applications?

Yes, you can. If you selected Brickplicators option to generate an LXF file, it is available as a link in the mail containing your full model.

A LXF file is a three-dimensional model or scene created by LEGO® Digital Designer (LDD). It can be loaded and refined by LDD. Rebrickable has a great explanation of everything needed at .

Step 5: ​Why Don't I See Any Colors in My Personal White House LEGO Building Instructions?

Since we used a 3D print STL file (which does not contain any colors) we only have one color as an output.

If we would have used a color model (such an FBX file) the generated plan would have been in full color too. So, if you would have downloaded this 1967 Shelby Ford Mustang from the build plan for your personal LEGO MOC would have looked much more colorful (see picture).