See the below image to see how it all works.The best, but also hardest, form of LEGO building is free-building. Try making your own bricks using just multiples of 0.8. In CAD-land it probably doesn't matter, and I created the #data block (in my library models) so that it can easily be changed. I use 7.2 because it's a multiple of 0.8, but physical measurements reveal that it's on the 7.4+ side. The Technic liftarm height is also in contention. Since the LEGO brick is taller than the Technic pin spacing and not square, a 45° connection would not connect properly for many bricks away from the origin. A Technic 'stack' is one of a few types of connected Technic beams. These have angles that behave with Technic 'stacks'. The bottom edge is not usually a 0.8 mm unit and is usually derived from the clearance of other pieces. Sloped bricks need to be researched (BricklInk) to find the angle of the slope. The major exceptions are sloped bricks, axle connectors, and some Technic features. There are many exclusions from this rule, not counting organic blocks (animals, hair, tools, etc.).

Studs are Ø4.8 by 1.6 high, one brick length/width is 8.0, brick height is 9.6, etc. These are also ideal representational dimensions since we're not going to manufacture these. Basic geometric bricks are made of only these dimensions. In the CAD world it doesn't really matter. Some people refer to the 'stud' and others refer to 'LU' (LEGO unit), with even more debate on what a LU is. There's some debate about what a 'unit is'. Both the shape number and color/brick number can be searched in BrickLink. That is the number that they inventory by.

That number is the color code combined with shape number. If you look in the back of the Build Instructions (those that have a parts list) you'll see a longer number. This is a number that corresponds to the shape only, as many colors can be cast in the same mold. I will refer to BrickLink ( but many others use similar methods:Īlmost every piece has a part number molded into the part, usually in the bottom 'female' side cavity, and usually consists of 4 to 6 digits (go ahead, look at your own bricks). Standard parts consist of square, circular, and angled blocks - regular geometric blocks. Most 'standard' parts can be created using only simple math. I get a lot of questions about how I create LEGO parts.

Lego brick cad