Quickly modify the edges of any STL.
Chamfers · Fillets · Hybrid Chamfillets
No upload. No installation. No account. No cloud processing.
Choose your STL, pick the edges, choose your finish, and export.
It only takes seconds.
The Mesh Editing Trap
We all routinely download STLs from MakerWorld, Printables, or Thingiverse, only to realize...
The traditional answer is often to boot up Fusion, FreeCAD, Blender, or Meshmixer. But that's enormous overkill for a single-operation modification.
Mesh editing is particularly unpleasant for this task. Fusion is excellent at parametric CAD, but an imported STL isn't a native parametric solid. Once you're dealing with mesh geometry, operations that feel trivial on a native CAD model quickly become a frustrating mess.
The Chamfilletizer fixes this. It treats your STL as exactly what it is—a mesh—and applies flawless, slicer-ready edge treatments in seconds.
How to Use The Chamfilletizer
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.
- Load a Model: Select your STL. The app will automatically repair minor mesh issues and center the camera.
- Select Edges: In Global mode, the threshold slider picks all sharp edges. Switch to Selective mode to click specific edges, or use the selection macros. (Tip: double-click to select connected edges).
- Configure Cut: Choose Standard Chamfer, Pure Fillet, or Hybrid Chamfillet. Adjust the size and ratio using the live cross-section preview.
- Queue & Execute: Click "Add to Queue" to prep the cut. Add multiple cuts if needed, then click "Execute Queue" to process the geometry.
- Export: Click "Export STL" to save your modified, slicer-ready mesh.
Selection Macros
- Base Edges: Selects only edges sitting flat on the build plate (fights elephant's foot).
- All But Base: Selects everything except the build plate edges.
- Top Edges: Selects edges at the absolute highest point of the model.
- Verticals: Selects straight up-and-down edges (rounds sharp box corners).
- Horizontals: Selects any edge parallel to the floor, regardless of height.
Under the Hood
The Chamfilletizer uses a robust, client-side geometry engine to ensure your exported STLs are manifold, printable, and mathematically sound.
Complete Workflow
- Auto-Cleaning: Automatically welds and cleans meshes upon loading.
- Smart Selection: Global threshold angles, individual edge picking, and double-click chain selection.
- Selection Macros: Instantly grab Base Edges, Top Edges, Verticals, or Horizontals.
- Live Previews: Three distinct edge profiles with visual cross-section previews.
- Batch Processing: Queue multiple operations and execute them at once.
- Non-Destructive: Full undo support for your last operation.
- Direct Export: Saves the finished mesh directly as a binary, slicer-ready STL.
Advanced Mesh Operations
- True Booleans: Actual modifications are performed using precise boolean unions and subtractions.
- Sweep & Frame Generation: Dynamic path classification handles shallow turns, miters, and bounded corners with automatic pullback.
- FDM Gravity Orientation: Profiles automatically orient flat edges toward the build plate.
- Error Prevention: Detects failed/unsafe sweeps and prevents degenerate triangles rather than blindly outputting broken geometry.
- Complex Topology: Native handling for closed loops, dynamic normals, and seamless manifold conversion.
Frequently Asked Questions
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 using WebAssembly. No STLs are ever uploaded to a server.
Support the Creator
If The Chamfilletizer made your life easier, buy me a Diet Coke or boost my models. I appreciate your support!
Feedback & Bug Reports
Have a bug report, feature request, or just want to share a successful print?