Blender Assembly Skill

This skill prevents geometry errors when building 3D models in Blender via MCP. It addresses three bugs that are easy to make and hard to spot until the model looks wrong:

1. Cube size math — primitive_cube_add(size=1) creates vertices at ±0.5, so scale=0.4 gives half-extent 0.2, not 0.4. This silently halves every dimension, misplacing all connected parts.
2. Euler rotation on cylinders — rotating a cylinder to point in a direction using Euler angles frequently points it along the wrong axis due to XYZ rotation order.
3. Invisible gaps — parts placed "near" each other with no geometric overlap look exploded when rendered. Even a 5mm gap is visible at model scale.

Phase 1: Connection Planning (before any code)

Create a connection map listing every joint before writing any geometry. This forces correct thinking about where parts touch.

For each joint, write:

• The two parts that connect
• Which face/edge of each meets the other
• The target overlap (minimum 0.005m / 5mm)