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Rig a 2-bone arm

Time: 40 minutes. Difficulty: Intermediate.

Take a simple arm mesh and rig it with a 3-joint chain + 2-bone IK, then paint weights for clean deformation. The "first real rig" tutorial.

Prerequisites

Import the mesh

File > Import > 3D Model… and pick your arm. View > Frame All (A) to center it.

Create the joint chain

  1. Press F3 (Rigging menu set).
  2. Rigging > Create Joint Chain (3). Three joints appear along the world Y axis.
  3. Switch to Move tool (W) and drag each joint into position:
  4. shoulder at the arm's shoulder.
  5. elbow at the elbow bend.
  6. wrist at the wrist.
  7. Right-click each joint > Rename to give them clear names.

Orient the joints

Rigging > Orient Joint > All in Chain aligns each joint's local axes so X points toward its child.

Bind skin

  1. Select the arm mesh.
  2. Shift-click the shoulder (chain root).
  3. Rigging > Bind Skin to Selected Mesh.

The Designer assigns initial weights by distance.

Add 2-bone IK

  1. Select the wrist (chain tip).
  2. Rigging > Solve 2-Bone IK on Selected Chain.

An IK handle placement appears at the wrist. Move it; the chain follows.

Paint weights

The auto-bind is approximate. Refine:

  1. Select the elbow joint.
  2. Rigging > Paint Weights > Set Active Joint (from selection).
  3. B to activate Brush; the mesh tints by current weight.
  4. Paint elbow weight onto the upper-forearm region (vertices that should bend with the elbow).
  5. Repeat for the wrist with the lower-forearm and hand.

Rigging > Paint Weights > Smooth Selected smooths a hard boundary between two joints' influence.

Animate a wave

  1. F4 (Animation menu set).
  2. Frame 1: IK handle at neutral. Press S to set a key.
  3. Frame 12: drag IK handle up and right (the arm raises). S.
  4. Frame 24: back to neutral. S.

Space to play. The arm waves.

Cleanup

G to open Graph Editor. Select all keys, click Auto Tangent in the toolbar. Curves soften.

Export

File > Export > .esk Bundle. The bundle ships the rig + a 24-frame wave animation track.

What you exercised

  • Joint chain creation + orient.
  • Skin bind.
  • 2-bone IK solver.
  • Paint weights.
  • Keyframing on an IK handle.
  • Graph Editor cleanup.

See also