How to Convert 3D Models into STL Files Using ZBrush
Step 1: Ensure Decimation Master and 3D Print Exporter are Installed
- Check Plugin Installation
- Open ZBrush and navigate to the Zplugin menu.
- Ensure that Decimation Master and 3D Print Exporter are listed. If they are not, download them from Pixologic’s website under Support > Download Center > ZBrush Plugins.
- Follow the installation instructions provided with the plugin downloads.
- Decimation Master
- This plugin reduces the number of polygons in your sculpt while retaining details, making the model easier for the 3D printer to process and build efficiently.
Step 2: Decimate Your Model for MakerWare
- Prepare for Decimation
- Select Zplugin > Decimation Master and then click Preprocess All.
- Once preprocessing is complete, set a target polygon count. For example, use 25,000 polygons for a model around 60mm per side, which takes about 1.5 to 2 hours to build on a MakerBot.
- Adjust the sliders if needed and select Decimate All. Check the result and adjust the poly count higher if necessary to address any problem areas.
Step 3: Set Up 3D Print Explorer and Export to STL
- Open 3D Print Exporter
- Go to the Zplugin menu and open the 3D Print Exporter menu.
- Follow the steps carefully:
- Click Update Size Ratios.
- Set the measurement units to millimeters.
- Select one axis (e.g., the X-axis) and input the desired size. The other axes will update automatically.
- Choose to build all subtools, only visible polygons, or only selected subtools.
2. Export the STL File
- Click the STL button in 3D Print Exporter to create the STL file needed for MakerWare.
Step 4: Modifying Your Model to Avoid Supports (Optional)
- Avoiding Supports in MakerWare
- For models with significant overhangs, such as a head bust, you may want to avoid using supports by dividing the model.
- Use the Slice Curve brush in ZBrush to divide the model into polygroups at the widest part, which allows the MakerBot to build narrower sections more easily.
- Split the model into polygroups and use the Split Hidden command under the Geometry section of the Ztool menu.
- Note: Splitting the model will create hollow openings, so use more infill during printing to ensure proper adhesion.
- Export Each Subtool Separately
- In the advanced section of 3D Print Explorer, you can choose to export each subtool as a separate STL file.
Additional Tips and Considerations
- Scale and Units
- Ensure your model is correctly scaled before exporting. The units in ZBrush should match the units your 3D printer uses to avoid scaling issues.
- Wall Thickness
- Verify that your model has appropriate wall thickness. Thin walls may not print correctly or may be too fragile. Check your 3D printer’s specifications for minimum wall thickness requirements.
- Model Orientation
- Consider the orientation of your model in the 3D printer. Proper orientation can reduce the amount of support material needed and improve the surface finish.
- File Size and Complexity
- STL files can become very large with high resolution. Ensure your computer can handle the file size and that your 3D printer’s software can process it. Simplify the model where possible to reduce file size without compromising print quality.
- Manifold Geometry
- Ensure your model is manifold (watertight). Every edge should be connected to exactly two faces. Non-manifold geometry can cause errors during 3D printing.
- Software Updates
- Keep your ZBrush software and 3D printer’s firmware updated. Updates often include bug fixes and new features that can improve the export process and print quality.
- Test Prints
- Before committing to a full-scale print, consider doing a small test print. This can help identify any potential issues and save material and time.
By following these steps and tips, you can ensure a successful conversion of 3D models into STL files suitable for 3D printing, resulting in high-quality prints and efficient use of resources.