How to Use AI for CNC Projects: From Image to 3D Relief

Artificial intelligence has evolved rapidly in recent years—and it’s now a powerful tool for makers, designers, and CNC enthusiasts. Whether you’re creating custom carvings, signs, or decorative pieces, AI can dramatically speed up your workflow and unlock new creative possibilities.

In this guide, you’ll learn how to use AI for CNC projects, from generating images to converting them into 3D relief models ready for carving.

Why Use AI in CNC Design?

AI tools simplify some of the most time-consuming parts of CNC design. Instead of manually creating artwork or 3D models from scratch, you can:

• Generate custom artwork instantly
• Convert images into 3D reliefs
• Speed up prototyping and iteration
• Explore creative ideas you may not have considered

As a result, both beginners and experienced users can produce high-quality CNC projects faster than ever.

Step 1: Generate an Image with AI

To begin, you’ll need an image to convert into a 3D model. Tools like Google Gemini make this process simple.

Step 1: Generate an Image with AI

To begin, you’ll need an image to convert into a 3D model. Tools like Google Gemini make this process simple.

Tips for Better AI Image Prompts

Although generating images is easy, creating usable images for CNC carving requires some strategy:

• Avoid blurry or low-detail images
• Avoid overly complex textures
• Ensure strong contrast between elements
• Keep compositions clean and defined

For best results, try adding phrases like:

• “relief style”
• “high contrast”
• “engraving design”
• “black and white drawing”

These help produce images that translate better into carvable depth.

You can also upload an existing image and ask AI to:

• Clean it up
• Simplify details
• Convert it into a relief-style design

This is especially useful for logos, photos, or custom artwork.

For this article, I have prompted Gemini to make an image of wizard frogs. Below is the prompt exchange I used:

Step 2: Convert Your Image to a 3D Relief

Once your image is ready, the next step is turning it into a 3D model. Tools like Hitem3D specialize in AI 3D relief generation.

Why Use Hitem3D?

Hitem3D is one of the more popular tools for converting images into STL files. It offers:

• AI-generated 3D relief models
• Simple upload and processing workflow
• Adjustable depth and geometry settings

The platform includes a free trial with limited credits, allowing you to test multiple designs before committing.

Alternative AI Tools

Other tools you can explore include:

• SculptOK
• Depth-R
• Musely.ai

These typically generate depth maps, which can then be imported into CNC software and refined.

Step 3: Generate and Refine Your Model

Inside Hitem3D, you’ll find several generation modes, including:

• General (full 3D models)
• Portrait (3D busts)
• Texture
• 3D Relief (recommended for CNC projects)
• Segmentation

For most CNC carving applications, the 3D Relief option works best.

Key Settings to Adjust

After uploading your image:

• Background Removal: Decide whether to isolate the subject
• Base Type: Adjust or flatten the back of the model
• Shape: Choose square, rectangle, circle, or oval
• Scaling: Resize your model
• Height/Depth Slider: Increase depth for stronger carving contrast

Be careful with depth—too much height can cause carving issues or loss of detail.

Once satisfied, export your model as an STL file.

Step 4: Import Your STL into CNC Software

Next, bring your model into Designer 5.

Import Process

1. Navigate to the Import tab
2. Select Import STL
3. Adjust the pattern size (commonly around 8 inches wide)
4. Place the model on your board

At this stage, your design may already be carve-ready. However, additional refinement can significantly improve results.

Designer – STL Pattern Import

Step 5: Clean Up Your Model with Sculpting Tools

For best results, refine your model using Sculptor 2.

Common Adjustments

• Smooth unwanted artifacts
• Reduce harsh edges
• Fix surface inconsistencies
• Clean up background noise

AI-generated models can sometimes introduce imperfections—especially from lighting or reflections in the original image. Fortunately, tools like smoothing and lowering can quickly fix these issues.

Sculptor – 3D Sculpting Tools Overview

Sculptor 2 – 2D Editing Tools Overview

Real-World Project Ideas Using AI

AI opens the door to a wide range of CNC projects. For example:

Custom Family Portraits

• Convert photos into relief carvings
• Add frames, text, or decorative elements
• Use clipping tools for clean compositions

Decorative Artwork

• Replace backgrounds with textures
• Add flourishes and patterns
• Combine multiple AI-generated elements

Signs and Branding

• Generate business signage concepts
• Refine details before carving
• Add outlines and cut paths for production

Quick Creative Projects

Complete projects in minutes instead of hours

Generate landscapes, animals, or abstract designs

Add text and carve-ready paths

Pro Tips for Better CNC Results

To get the most out of AI-generated CNC designs:

• Keep designs simple and bold
• Avoid excessive micro-details
• Adjust depth carefully to prevent carving issues
• Use smoothing tools to refine final output
• Test smaller versions before full-size carving

If you have advanced tools like modeling add-ons, you can also:

• Blend edges using sweep features
• Create smoother transitions between elements
• Enhance overall design quality

For this example, we used an image of a family (you can use your own family pictures with the above steps). For this image, we added an oval frame and made a cut path. Our model was a square, so we made the pattern Inclusive clip, so only what was in the frame is shown. Make sure to remove the feather on the pattern.

For this picture, we removed the background and added a textured background. For the project we added a name and a small flourish.

Extra Tip

If you have the Modeling Suite add-on, you can use the sweep corner option and draw an angled line to blend together the borders of the image, the background, and carve region. This can also be done by drawing rectangles with a large draft if you do not have the Modeling Suite add-on.

Modeling Suite – Sweeps

This picture we found of cardinals turned into a great pattern that would work throughout many different projects.

This was a quick 5-minute project. I asked Gemini for a mountain range image, and the result was excellent. I added some text and made a cut path to cut it out.

Here is an example of a complex sign that you can make using AI. I prompted Gemini to make a sign for “Tom’s BBQ Pit”, and it gave an image like the one on the left. I had to refine this to remove a background it made and then remove some additional details that I did not like.

When I brought it to Designer 5, I took it to Sculptor 2 first, and smoothed out the edges some to get rid of stray elements. On the board I placed it on a 20″ by 12″ board. I decided to lower the height to around 60, to avoid the smaller details from being too tall and causing issues with the carve. I used the outline tool to create an outline and then offset it a small amount. The offset outline was then made into a pierced carve region. Finally, I added tabs to make sure the project will not break off and cause issues. With a 1/4″ carving bit selected for the roughing bit, and a 1/16″ carving bit selected as a carving bit, the estimated carve time is 4 hours.

Final Thoughts: AI + CNC is a Game Changer

Combining AI with CNC technology transforms how projects are created. What once took hours of manual design can now be done in minutes—with more flexibility and creative freedom.

Whether you’re making signs, artwork, or custom products, AI tools like Google Gemini and Hitem3D can help you go from idea to finished product faster than ever.

As AI continues to improve, its role in CNC design will only grow—making now the perfect time to start integrating it into your workflow.