Part Designer (LEGO Technic-compatible parts)

About this generator

Part Designer is a free browser tool that builds custom parts to fit LEGO Technic pins and axles, made by developer Marian Kleineberg (marian42). You do not draw anything. You assemble the part on a 3D grid one block at a time, and each block is a pin hole, axle hole, pin, axle, solid cube or ball joint. For every block you pick the direction (X, Y or Z), full or half size, and rounded or square edges.

You can start from an empty grid or load one of 59 existing Technic parts from the catalog, such as beams, cross blocks, bushings and angle connectors, and change it into the piece you are missing. A Measurements panel with 17 settings, most of them in mm, lets you adjust the Technic unit and the pin hole and axle sizes to suit your printer. Save STL downloads the print file, Save Studio part writes a .part file for BrickLink Studio, and Share puts a link in the address bar that rebuilds the part.

It suits Technic builders who need a beam length, bracket or connector that LEGO never made. There is no undo and nothing is stored between visits, so press Share and keep the link if you want to come back to a design.

What you can make

• Technic-compatible beams and half beams
• Cross blocks and angle connectors
• Custom axles and pins
• Ball joint connectors
• Frames and right-angle bent beams

How to use Part Designer

1. Open the page, then load a part from the Catalog or press Clear to start empty
2. Move the cursor by dragging its colored arrows or with the arrow keys and PgUp/PgDown
3. Pick size, orientation and edges, then click a block type to place it at the cursor
4. If holes print too tight or too loose, change the Measurements and click Apply
5. Click Save STL, then slice and print the part