This is intended to be a "pretty good" tool for applying simple chamfers, fillets, and hybrid chamfillets to basic STL files. It is a quick-fix for the most common applications rather than a silver bullet for highly complex meshes.
When you add an operation to the queue, a 3D preview of the cutting tool will appear on your model.
Whenever a yellow warning cutter is generated, a ⚠️ caution badge will appear next to that specific operation in your Queue Tray. You can hover your mouse over this badge to read the specific diagnostic reason:
Note: A yellow warning does not block you from executing the cut. The tool will still attempt the operation, but you should inspect the exported STL closely in your slicer.
When an open edge terminates directly against a planar surface, The Chamfilletizer can trim the completed cutter at that surface before performing the Boolean operation. This protection is independent of the surface's orientation.
Supported examples include:
This protection applies only when the obstruction is positively identified as a planar surface connected to the open edge endpoint. It is not general collision detection. Curved surfaces, disconnected nearby objects, ambiguous multi-face junctions, and severely defective STL topology may not be handled reliably.
If The Chamfilletizer made your life easier, buy me a Diet Coke or boost my models. I appreciate your support!
The Chamfilletizer is an edge-treatment tool, not a full CAD system. It is designed to make localized chamfers, fillets, and chamfillets on existing STL models. It does not attempt to provide the feature history, parametric modeling, or complex surface-editing capabilities of a CAD program.
Don’t expect it to:
When The Chamfilletizer cannot safely perform an operation, it may skip that operation rather than risk damaging your model. A successful operation does not mean the geometry is suitable for every downstream use. Always inspect important results before manufacturing.
The cutter can be trimmed when an open edge terminates directly against a positively identified planar obstruction. The obstruction may have any orientation, so this can include floors, ceilings, vertical walls, ramps, roofs, and other planar stops.
This handling is deliberately limited. The tool does not promise reliable protection against every type of nearby geometry.
If the application cannot identify a single suitable planar obstruction at an open endpoint, it may leave the cutter unchanged or reject the operation. Always inspect important results in your slicer.
What kind of models work best?
Functional, mechanical parts. If you are modifying a simple bracket, a cable winder, or a modular storage crate, this tool works great. Highly organic models may have too many intersecting faces for the edge-cutters to resolve cleanly.
Why is a cut failing or taking so long?
Processing is done entirely locally in your browser. High-polygon STLs take longer to calculate. If the tool folds over itself on very tight corners, it will skip the cut to prevent breaking the mesh. Try a smaller size.
What is a "chamfillet"?
A chamfillet is a hybrid edge treatment combining a chamfer and a fillet, designed specifically for FDM 3D printing. Standard rounded fillets create extreme overhangs that print poorly. A chamfillet solves this by starting with a straight, printable chamfer at the base, which smoothly transitions into a curved fillet. This provides the aesthetic of a rounded bottom edge without requiring support material.
Why did my model disappear?
Your original STL must be manifold (watertight). If the mesh has holes, non-manifold edges, or severe self-intersections, the boolean math will fail. Repair the STL in your slicer or CAD software first.
Is my data sent anywhere?
No. The entire application runs locally. No STLs are ever uploaded to a server.
Have a bug report, feature request, or just want to share a successful print?
© 2026 David Haddock. All rights reserved.
This software is free to use, modify, and distribute for noncommercial purposes under the PolyForm Noncommercial License 1.0. It is perfect for hobbyists, educational use, and personal FDM printing workflows.
Restrictions: You may not monetize this software, re-host it behind ads or paywalls, or integrate it into a commercial product or service without prior written authorization.
Note: This license applies to the software code itself. The output STLs you generate belong entirely to you, and you may use or sell those physical prints or digital files however you wish.
For the full legal text, visit PolyFormProject.org.
Last updated: September 2026
1. Your 3D Models and Data
The Chamfilletizer is a client-side WebAssembly application. All 3D model processing and edge modifications happen entirely locally on your device. We do not upload, collect, store, or have access to your STL files or design data.
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