3DM file: the Rhino format in jewelry CAD
A 3DM file is Rhino's native file format, and MatrixGold saves it too. It stores a design as exact NURBS curves and surfaces, along with the units it was drawn in and its named layers. In jewellery CAD it is the working file, and meshes such as STL or GLB are exported from it for printing and the web.
3D Jewelry Designer1 min read
What a 3DM file holds
NURBS, short for non-uniform rational B-splines, describe each surface mathematically, so a band stays smooth at any zoom. A normal save also keeps render meshes, the triangles a browser draws. Save Small strips them, and a file saved that way can show little or nothing.
The file also records its units, such as millimetres or inches, so the piece can be measured and weighed at its real size. Layer names, and which objects are hidden, are saved with it too.
3DM, STL and GLB
An STL is a bare mesh with no units, parts or materials. A GLB keeps separate parts and materials, but as a mesh made for the web and AR. The format comparison sets them side by side.
Opening a 3DM file
You do not need Rhino. The free 3DM viewer reads one in your browser with Rhino's own open file library, without uploading it, and lists each part with its layer. In the studio a .3dm opens directly, with metals, stones and prongs detected from layer and object names: see Rhino and MatrixGold rendering.
See also: how to open a 3DM file without Rhino.
Questions
Can a 3DM file be converted to STL or GLB?
Yes, Rhino exports both. Keep the .3dm as the master, because a mesh cannot be turned back into the exact curves it came from.
Related
- 3DM Viewer: Open Rhino Files Online for Free
Open a Rhino or MatrixGold .3dm file in your browser, rendered as jewelry, with layers, metals and stones detected. No Rhino needed.
- How to open a 3DM file without Rhino
Open a .3dm file without Rhino: the free 3DM viewer shows it in your browser in real metal and stone materials, and the studio renders and shares it.
- Render Rhino and MatrixGold jewelry files online
Upload a Rhino or MatrixGold .3dm and render it as photoreal jewellery in your browser, with its units and layers kept and metals and stones detected.