Brick Parts Classification Guide: Basic Bricks to Technic

One builder calls it a "2x4 brick," another calls it "3001," and a third just knows it by color. That gap in part vocabulary is exactly what slows a build down. A working knowledge of part categories is what lets you find the piece you need in seconds, whether you are rebuilding a design from brickplan.cn or drafting your own. Name the part, state the spec, and your efficiency doubles.

1. The Basic Logic Behind Part Categories

Before digging into part names, it helps to understand how the system is organized. After decades of evolution, brick systems settled on a standard built around the stud as the base unit. The most common ways to slice the catalog are:

• By function: basic bricks, plates, slopes, special pieces
• By size: length and width measured in studs
• By line: classic system, Technic, DUPLO and other scales

Once these categories click, you can open a parts list on brickplan.cn and immediately recognize every entry on it.

2. Basic Brick Categories

2.1 Standard Bricks

Standard bricks are the foundation of the whole system, with a fixed height-to-width ratio. The most common sizes are:

• 2x4 brick: the classic piece, used in nearly every MOC
• 2x2 brick: the basic unit for small structures
• 1x2 brick: good for filling small gaps
• 1x1 brick: the smallest standard brick, usually for decoration and detail

2.2 Plates

Plates are thinner than standard bricks, standing one-third the height. In MOCs they are used for:

• Floors and walls: covering large areas
• Height adjustment: using the one-third height difference for fine-tuned structures
• SNOT building: attaching plates sideways for studs-not-on-top construction

Common plate sizes in any parts chart include 1x1, 1x2, 1x4, 2x2, 2x4 and 2x6 plates.

2.3 Slopes

Slopes create angled shapes such as roofs and car hoods. The usual suspects:

• 45-degree slope: the classic slope, standard for roofs
• 33-degree slope: a gentler angle
• Inverted slope: used under hoods and similar overhangs
• Curved slope: arched pieces for domes and rounded forms

3. Special Function Parts

3.1 Connectors

Connectors are the soul of MOC building, the pieces that make complex structures possible:

• Clip: grips another part or an axle
• Hinge: creates moving structures like car doors and wings
• Ball joint: for robot arms, legs and anything needing multi-angle rotation
• Cross-axle connector: the core connector of the Technic system

3.2 Technic Parts

Technic parts are the heart of mechanical MOCs and the most distinctive category in any classification scheme:

• Axle: transfers rotational motion
• Gear: changes the direction and speed of a drivetrain
• Beam: forms the frame of a mechanical structure
• Pin: joins axles to beams
• Differential: allows wheels to turn at different speeds

Technic MOC instructions on brickplan.cn lean heavily on these parts, especially the Technic designs from Double Eagle and Mould King.

3.3 Window and Door Parts

• Window frames: in a range of sizes
• Glass panes: transparent or translucent
• Door panels: many styles, including swing doors, sliding doors and revolving doors
• Fences and railings: for balconies and barriers

4. Part Sizes and Naming Conventions

The key to part names is understanding the naming rule. A complete part name usually contains these elements:

Type + Size + Color + Special note

For example:

• "2x4 red standard brick"
• "1x2 transparent glass pane"
• "2x2x2 45-degree gray slope"

On brickplan.cn, every instruction set comes with a detailed parts list, and the names in that list follow this convention, so you can match pieces straight to the diagram.

5. Sorting and Storing Your Parts

Once your collection grows, storage becomes critical. Here is a system that has been tested in practice.

5.1 Sort by Color

• Pros: visually tidy, easy to scan
• Cons: needs a lot of containers, and hunting a specific part is slow

5.2 Sort by Type (Recommended)

• Group A: basic bricks (2x2, 2x4 and so on)
• Group B: plates in all sizes
• Group C: slopes and curved slopes
• Group D: Technic parts (gears, axles, beams)
• Group E: special pieces (windows, doors, wheels, minifigure accessories)

5.3 Storage Tools

• Clear compartment boxes: best for small parts
• Drawer cabinets: best for large volumes
• Label stickers: mark what goes in every compartment

6. Buying Parts from a Parts List

After downloading instructions from brickplan.cn, you usually end up with a complete parts list. From there:

1. Check your inventory first: compare the list against what you already own
2. Buy the gaps: source missing parts from brands such as Qiji and Gobricks
3. Look for substitutes: if a specific part is unavailable, ask the brickplan.cn community for an alternative

7. Applying Part Knowledge in Real MOCs

Memorizing names alone accomplishes little. What matters is putting that knowledge into the build: knowing which piece gives you a curved surface, and which piece can stand in when something is missing. For example:

• Building a castle, you use slopes for the roof and plates for wall texture
• Designing a sports car, you use curved slopes for the streamlined body and Technic parts for the steering
• Creating a mech, you use ball joints for articulated limbs and clips to hold the weapons

You will see these techniques across the instructions on brickplan.cn. Build more, look closely, and your part vocabulary deepens on its own.

Wrapping Up

You do not need to memorize the whole catalog. Hold on to one thread: basic bricks, plates, slopes, connectors, Technic parts and window and door pieces, each in its own family. Once the classification logic is clear, you will always know what is within reach and what is missing on your desk.

Head to brickplan.cn, pick an instruction set and start building. Learning parts while you build beats reading about them every time.