Outline & Topics Covered
- What is an STL file?
- What is a 3DM file?
- Key differences: editing vs manufacturing
- Which format should you download?
- Do professional libraries include both?
The Two Core File Formats in Jewelry CAD
Every professional jewelry CAD workflow relies on two critical file formats: 3DM for design and editing, and STL for manufacturing and 3D printing. Understanding the difference is essential before purchasing or downloading any jewelry CAD files.
What Is an STL File?
An STL (Standard Tessellation Language) file converts 3D geometry into a mesh of triangular faces. It is the universal language of 3D printers and CNC milling machines. When you send a file to a wax 3D printer (Formlabs, Solidscape, EnvisionTEC), it must be in STL format. STL files are a one-way export — they cannot be easily re-edited in CAD software because all parametric geometry is converted into static triangles.
What Is a 3DM File?
A 3DM file is the native Rhinoceros 3D format. It stores geometry as NURBS (mathematically precise curves) rather than triangles. 3DM files are fully editable — you can resize the ring, change prong heights, adjust stone seat dimensions, or modify any surface in Rhino or MatrixGold without rebuilding from scratch.
Key Differences at a Glance
- 3DM → Edit in Rhino / MatrixGold → Full parametric control → Cannot be printed directly
- STL → Send to 3D printer → Cannot be edited → Required for casting workflow
Which Format Should You Download?
If you want to customize or resize a design, you need the 3DM source file. If you want to print and cast immediately without editing, the STL file is sufficient. For professional use, always obtain both.
Our Library Provides Both
Every design in the Jewellery Supermart library is delivered with both a 3DM source file for editing and a pre-validated STL file ready for wax printing. This gives you complete flexibility — edit the design to match a client's custom specifications, then export your own STL, or use our pre-checked STL directly.