File formats
STEP
Also known as: step · .step · .stp · iso 10303
Short definition
STEP is a CAD interchange format that stores a part's exact geometry as mathematical surfaces rather than as an approximated triangle mesh.
Full definition
When an author publishes a STEP alongside the STL they are giving away something valuable: the real, editable geometry in any CAD package rather than an already-triangulated mesh. With a STEP you can change a hole diameter, lengthen an arm or adjust a tolerance; with an STL you can only deform triangles. It is standardised as ISO 10303 and exported by Fusion, FreeCAD, Onshape and practically any parametric CAD. The trade-off is that slicers must convert it to a mesh before slicing, which they now do by themselves.
Related terms
- STLSTL is a file format that describes a 3D object's surface as a mesh of triangles, with no colour, no units and no printing information.
- 3MF3MF is a modern file format that, on top of geometry, stores colour, materials, units, object hierarchy and sometimes the slicer's full settings.
- ToleranceTolerance is the clearance you must leave between two parts so they fit, because 3D printing never reproduces the nominal dimension exactly.
File formats
Updated