Rig Any 3D Model Instantly with This Open Source AI Tool
Rigging 3D characters by hand takes hours and is the number one reason most AI-generated 3D models never make it into a game. This guide shows you a fully automated pipeline that takes any 3D mesh, rigs it, and turns it into a playable Unreal Engine character — all locally for free with just 6GB of VRAM. This works on humanoids, dragons, dogs, and more using the same one-click process.
What You'll Learn
Prerequisites
Before starting, ensure you have:
- ComfyUI installed (see our ComfyUI Installation Guide)
- Blender 4.2 or newer installed and added to your system PATH
- At least 6GB VRAM on your GPU
- Python 3.12 with PyTorch 2.8 and CUDA 12.8 (set up via the Trellis 2 installation guide)
- The ComfyUI Easy Install package (recommended for add-on management)
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Step-by-Step Process
Step 1: Download and Install Skin Tokens
- Visit the download page at
pixelminus-artistry.com/kintoken(link also in the video description) - Download the installer by clicking the three dots next to
skin_tokens_install.batand selecting Download - Place the installer into your
add-onsfolder inside the ComfyUI Easy Install directory - Run the installer by double-clicking
skin_tokens_install.bat— it will automatically download all models and install dependencies
Installation Details
The installer handles everything automatically: downloading models, installing dependencies, and setting up the environment. The installation is complete when you see "Skin tokens installation complete" in the terminal output.
Blender PATH Requirement
Blender 4.2 or newer must be on your system PATH. If the installer doesn't add it automatically, manually add it:
- Press Windows + R, type
sysdm.cpl, and go to Advanced - Click Environment Variables, find the Path variable, and click Edit
- Add the path to your Blender installation folder
Pro Tip
The Hanon Motion installer (hanon_motion_install.bat) is optional — only download it if you plan to use that tool separately.
Step 2: Launch ComfyUI and Load the Workflow
- Start ComfyUI by double-clicking
start_comfyui.batin your ComfyUI Easy Install folder - Download the workflow from the same download page — select the Pixel Artistry Skin Token Default Workflow and click Download
- Load the workflow by dragging and dropping the downloaded file into the ComfyUI interface
- Verify no red nodes appear — if everything is installed correctly, all nodes should load without errors
Pro Tip
Save the workflow file to a convenient location on your computer for easy access in future sessions.
First Load Time
The first time you load the workflow, it may take extra time as it downloads additional models in the background. This is normal — subsequent loads will be faster.
Step 3: Configure the Rigging Settings
- Select your model from the three available options — the first model generally gives the best results
- Upload your 3D model using the Load 3D and Animation node (supports FBX and GLB formats)
- Configure the Skin Tokens Rig Generator node with these recommended settings:
- Use Skeleton: Enabled
- Transfer Option: As needed
- Post Process: Always turn on for best results
- BPY Server Mode: Set to Headless
- Choose output format — select Unreal Engine 5 if importing to UE5, or FBX for general use
Model Sources
You can generate 3D models using Trellis 2 (see our Trellis 2 guide for details) or use any existing 3D mesh. The tool accepts standard 3D file formats.
Pro Tip
For humanoid characters, the default settings work great out of the box. For exotic animals like dragons or dogs, the tool automatically recognizes body parts like wings, tails, and four legs.
Step 4: Run the Rigging Process
- Click the queue button in ComfyUI to start the rigging process
- Wait for completion — the process typically takes around 180 seconds for standard models
- Blender will launch in the background automatically during the process
- Check the output — the rigged model saves to your ComfyUI output folder as an FBX or GLB file
Rigging Complete!
Once complete, you'll have a fully rigged character with fingers, tail, ears, and all body parts automatically recognized and weighted. The skeleton is ready for animation.
Pro Tip
You can test the rig directly in the ComfyUI viewport by selecting bones and moving them around. This lets you verify the rig works before exporting.
Skin Weight Adjustments
For non-humanoid characters (like the wolf example in the video), you may need to manually adjust skin weights in Blender:
- Select the armature and mesh
- Enter Weight Paint mode
- Select the problematic bone
- Use the brush to remove weights from areas that shouldn't move with that bone
Step 5: Import and Set Up in Unreal Engine 5
- Create a new Third Person project in Unreal Engine 5
- Create a folder (e.g.,
Char) in the Content Browser - Import your rigged model — use the GLB file from your ComfyUI output folder (FBX has scaling issues)
- Double-click the imported mesh, go to Skeletal Mesh, and save the found files
- Create a Control Rig — right-click the skeletal mesh and select Create > Control Rig
- Set up animation retargeting:
- Find the ABP_Unarmed animation blueprint
- Right-click and select Retarget Animations
- Select your mesh as the target
- Export all animations to your project folder
Fixing Squashed Legs
When you first open the animation blueprint, the character may appear with squashed legs. Fix this by:
- Double-click the Animation Graph
- Double-click the Control Rig node
- In the Details panel, change the Control Rig Class to the one you created
- Right-click and Refresh Nodes, then Compile
- The character should now stand correctly
Pro Tip
To make your character playable:
- Open the ThirdPersonCharacter blueprint
- Change the Anim Class to your new
NM_ABP_Unarmedblueprint - Change the Character Mesh to your rigged mesh
- Adjust Scale and Location as needed
- Click Compile and Save
Playable Character!
Press Play in Unreal Engine to test your character. You can now run around with your AI-rigged character in a fully playable game environment.
Advanced Workflow: Full Pipeline from Concept to Game Asset
Complete Asset Pipeline
The video demonstrates a complete pipeline for turning concept images into production-ready game assets. While the core rigging is covered above, here's the full workflow for professional results:
- Generate your 3D model using Trellis 2 with the high-quality workflow (see our Trellis 2 guide)
- Import into Blender and merge vertices (select all, right-click, Merge Vertices) to fix mesh holes
- Export as FBX for the next step
- Retopologize using Hanon 3D Studio (free, up to 20 generations):
- Go to
3d.hanuang.global.com - Open 3D Studio, click Roll, then Retopology
- Upload your mesh and wait for processing
- Go to
- UV Unwrap in the same tool for proper texture mapping
- Download as FBX
- Re-export your retopologized mesh as GLB from Blender
- Use the Trellis 2 Texture Projection workflow in ComfyUI (see previous tutorial)
- Upload your reference images and run the workflow for better texture quality
- Fix texture issues using Modif (free, 2K version):
- Import your mesh at
modif.com - Create a new layer
- Select areas to repaint (e.g., face, back)
- Generate and save as
textured_mesh.obj
- Import your mesh at
- Load your textured mesh into the Skin Tokens workflow
- Select Unreal Engine 5 as the output format
- Run the workflow again — the textured character will be rigged automatically
- Import into Unreal Engine following Step 5 above
Related Guides
- ComfyUI Installation Guide - Complete installation process for ComfyUI and custom nodes
- Running ComfyUI on RunPod - Cloud GPU setup for faster generations
- Deploy Your First RunPod - Basic RunPod account and pod management
Next Steps
Now that you've completed this guide:
- Experiment with different model types — try rigging animals, creatures, and stylized characters
- Refine skin weights in Blender for perfect deformation on complex models
- Create custom animations in Unreal Engine using your new control rig
- Explore the full CustomUse pipeline mentioned in the video for turning concept art into complete game assets
- Check out the Trellis 2 guide for generating your own 3D models from scratch