Hi everyone,
I’m building Forma3D, a free browser-based STL editor focused on quick edits for 3D printing.
The idea is not to replace Fusion/Blender/CAD software, but to make common STL fixes easier when you just need to modify a downloaded model without rebuilding it from scratch.
It runs locally in the browser: files are not uploaded to a server.
Current features include:
\- Open and export STL files
\- Select faces or whole connected bodies
\- Push/Pull flat faces
\- Shorten a model along X/Y/Z without scaling it
\- Split a model into two parts and export each side
\- Hollow / shell a model with wall thickness
\- Add/subtract simple solids: box, cylinder, cone, pyramid
\- Add 3D text
\- Create 2D profiles and push/pull them
\- Mechanical joint presets: arc, dovetail and T-slot
\- Object/body panel with select, rename, duplicate/pattern, export and delete
\- Basic mesh repair
\- Undo/redo with Ctrl+Z, Ctrl+Y and Ctrl+Shift+Z
\- English/Italian UI
A recent user here gave me a practical example: shortening a fridge door shelf bin STL without simply scaling it, because scaling would ruin the locking features and fillets. That feedback led to improving the Shorten tool so it now closes cut profiles better on rounded geometry.
I’d really appreciate feedback from people who often download STLs and need small functional edits before printing.
The project is here:
https://lukethehawk.github.io/Forma3D/
GitHub:
https://github.com/lukethehawk/Forma3D
Things I’m especially interested in:
\- Does the workflow feel understandable?
\- Which STL edit do you often need but current tools make annoying?
\- Does Shorten/Split/Hollow behave as you would expect?
\- Are there cases where the mesh result looks wrong or slicers complain?
\- What would make this useful enough to keep bookmarked?
It’s still early and mesh-based, so complex/non-manifold STLs can still be tricky, but I’m trying to improve it based on real print use cases rather than guessing.
Thanks!