How to Work With STL Files in SOLIDWORKS

Contents

STL files are mesh files made from triangles. They are common in 3D printing and scanning workflows, but they do not behave like normal SOLIDWORKS feature-based parts. You can open and inspect STL files in SOLIDWORKS, but editing them depends on how the mesh imports and how complex it is.

The most important choice happens before import: decide whether the STL should come in as a graphics body, surface body, solid body, or mesh body, depending on your SOLIDWORKS version and the file quality.

STL file opened in SOLIDWORKS — STL files are mesh data, not normal parametric SOLIDWORKS features.

Open an STL file

Click File > Open.
Set the file type to STL.
Select the STL file.
Click Options before opening.
Choose the import type that matches the work you need to do.
Open the file and inspect the result.

SOLIDWORKS STL open options — Use import options before opening the STL file.

Choose the right import type

Graphics body: best for visual reference when the file is large or does not need editing.
Solid body: useful when SOLIDWORKS can convert the mesh into a solid body.
Surface body: useful when the mesh can become surfaces but not a closed solid.
Mesh body: useful in newer workflows where mesh tools are available.

A very dense scan or downloaded 3D-print file may be too heavy to convert cleanly. In that case, use it as reference geometry or simplify it before trying to edit it.

STL import type in SOLIDWORKS — The import type affects what you can do with the STL after opening it.

Edit an STL file carefully

If the STL imports as a solid or mesh body, you may be able to cut, add features, measure, or reference it. However, you will not get the original feature tree back. An STL made from a detailed model is still a triangle mesh, so simple edits are much easier than rebuilding the full design history.

STL mesh body in SOLIDWORKS — Mesh files can be inspected, but they may not edit like native SOLIDWORKS parts.

Use STL files as reference geometry

For reverse engineering, it is often better to use the STL as a reference and create new sketches and features over it. Measure key distances, create reference planes, and rebuild clean parametric geometry where needed.

For measurement basics, see how to measure in SOLIDWORKS. For exported formats, see converting SOLIDWORKS to OBJ.

Using STL geometry as reference in SOLIDWORKS — Using the mesh as reference often produces a cleaner editable model.

Troubleshooting STL imports

The file opens slowly: the mesh may have too many triangles; simplify it before importing.
Solid import fails: try surface or graphics body import, then use the mesh as reference.
The model is the wrong size: check STL units during import.
The body is hard to edit: remember that STL does not contain the original feature tree.
Faces look faceted: that is normal for triangle mesh geometry.

STL troubleshooting in SOLIDWORKS — Most STL problems come from mesh density, units, or expecting feature history that is not in the file.

Finished STL workflow in SOLIDWORKS — Choose the workflow based on whether you need viewing, measuring, printing, or true editing.

Reference: current SOLIDWORKS mesh-file guidance describes import options for STL, OBJ, OFF, PLY, and related mesh formats, including graphics, surface, solid, and mesh-body workflows depending on version and file quality.