STL File Splitter

Split an STL mesh into a grid of smaller pieces along the X and Y axes. Choose the number of divisions or specify a printer's maximum X/Y dimensions so the tool calculates them.

This fork includes a Streamlit interface as well as the original command-line script.

Hosted app

Terminal demo

Recorded with VHS. Recording source and instructions.

Install

Use a Python version compatible with the dependencies in requirements.txt.

git clone https://github.com/SpyC0der77/stl-file-splitter.git
cd stl-file-splitter
python -m pip install -r requirements.txt

Web interface

streamlit run streamlit_app.py

Upload an STL, choose the split settings, and download the resulting parts as a ZIP file. The interface displays model and segment dimensions.

Command line

python split-file.py model.stl --xsplit 4 --ysplit 3
python split-file.py model.stl --max-x 200 --max-y 200
python split-file.py model.stl --xsplit 3 --max-y 150 --flip

Option	Behavior
--xsplit N	Number of X divisions
--ysplit N	Number of Y divisions
--max-x N or -mx N	Maximum X dimension used to calculate divisions
--max-y N or -my N	Maximum Y dimension used to calculate divisions
--flip	Rotate the model 180 degrees around the X axis before splitting

Explicit split counts take precedence over maximum dimensions on the same axis. With no settings, both axes default to one division. The CLI writes non-empty parts beside the input file as model_splt-01.stl, model_splt-02.stl, and so on.

Limitations

Splitting uses Trimesh boolean intersections and the manifold3d backend. Mesh validity affects whether intersections succeed. STL files have no standard unit metadata; the dimension settings assume the input coordinates represent millimeters. The tool does not add alignment pins or connectors to the pieces.

License

MIT. The fork is based on joeatbayes/stl-file-splitter.