MOC Curved Structures: Hinges, Wedges & SNOT Techniques
Build MOCs for a while and a pattern shows up: straight walls and right angles almost assemble themselves, but the moment you want a round tower, a curved roof or a streamlined car body, the bricks seem to fight back. In practice, curved structures follow a few reliable rules. Once you know which parts do the work and in what order to use them, a smooth surface is not much harder than a flat one. This guide covers the core techniques.
Why Curved Structures Are Hard: The Core Problem
Bricks are a right-angle world by design. Every brick and plate is square, so a curve can only come from one of two ideas: replace right-angle connections with angled parts, or stack many small pieces to build up a stepped, gradually changing outline. Understand those two routes and you stop freezing in front of a circle.
Hinges: Angles on Demand
The hinge is the entry-level tool for curved work. It introduces a fixed angle between standard bricks, and the common versions are 1x1 hinge bricks, 1x2 hinge plates and hinge pieces with a 45-degree detent.
- 1x1 hinge brick: good for polygonal approximations of a circle, such as a hexagonal tower
- Detent hinges: hold fixed angles of 0, 22.5 or 45 degrees, which makes rings and curved walls much easier
- Tip: build the curve from several hinge segments; the smaller the angle per segment and the more segments you use, the smoother the result
For example, a round tower can be made from eight 45-degree hinge sections closed into a ring, then levelled on the outside with thin plates. That is a classic first exercise for curved building.
1x1 Wedge Bricks and Slopes: Refining the Curve
Hinges alone get you a polygon. To move from polygon to genuinely round, bring in wedge bricks and slopes.
| Part | Purpose |
|---|---|
| 1x1 wedge brick | Fills the stepped gaps on the outside of the curve so the outline reads smoother |
| 2x2 round corner brick | Creates a smooth right-angle transition quickly |
| Curved plate | A plate with a built-in arc that can be laid straight onto a curved frame |
| Slope | Pairs with curved layers to create gentle gradients and a streamlined feel |
Tip: build the curved skeleton with hinges first, fill and level the gaps with wedge bricks, then cover the surface with curved plates. Three steps and you have a rounded surface that feels right in the hand.
SNOT and Sideways Building: The Secret Weapon for Arcs
SNOT (Studs Not On Top) earns its place in curved structures too. Turning bricks sideways lets you use side studs to build a curve in the horizontal plane, rather than simply stacking vertically.
Take a streamlined car nose: lay a turntable at the base as a rotation reference, then extend outward through side studs layer by layer, narrowing gradually into an arc profile. The same approach works for rounded hulls, arches and statue bases.
Tire Rings: A Ready-Made Circle
Many builders overlook a treasure here: tires. Different tire and wheel combinations are naturally perfect rings. Whether you need a mechanical bearing ring, a band around a planet or an energy ring for a sci-fi scene, you can drop one in directly. Combined with a round base, you can assemble a tidy circular structure in minutes.
Round Base Techniques: Where Every Curve Starts
To get a clean circular structure, start by getting the base right. Common approaches:
- Centre-axis method: use a turntable as the centre point and lay bricks in rings around it so the build stays symmetrical
- Pythagorean positioning: use corner bricks and a symmetrical layout to build an accurate regular polygon base
- Fill-and-sand method: lay a large block first, then trim the edges into a curve with small pieces
If the base is true, the curved structure above it will stand up and rotate properly.
A Practical Progression: From Small Circles to Large Curves
- Step 1: build an eight-sided tower from hinges to understand how multiple segments approximate a circle
- Step 2: add wedge bricks and curved plates to smooth the tower into a rounded column
- Step 3: try SNOT sideways building for horizontal arcs on a car nose or a hull
- Step 4: combine tire rings with round bases to complete a sci-fi ring structure
Curved building is a skill that improves with feel. Take a model apart and rebuild it a few times and you will develop your own rules of thumb. If you want more plans with curved structures to practise on, browse the architecture and vehicle categories on brickplan.cn and reverse-engineer finished designs — progress comes fast that way.
Curves are one of the most rewarding things you can build with bricks, and hopefully this guide makes them easier to reach for.