Parametric Editing vs. Direct Editing: A Guide for CAD Users Transitioning to Onshape

When transitioning from CAD systems like SOLIDWORKS to Onshape, experienced mechanical engineers need to understand both the similarities and unique strengths each platform offers.

Both SOLIDWORKS and Onshape utilize powerful parametric modeling systems, relying on feature histories and associative relationships to drive design intent. However, working with imported geometry or legacy parts often calls for robust direct editing capabilities beyond traditional parametric workflows.

In particular, engineers who manage extensive libraries of imported components, such as vendor-supplied commercial-off-the-shelf (COTS) items or standardized parts, will find significant value in Onshape’s cloud-native management of parts libraries.

Parametric Editing: Familiar Strengths

Parametric modeling forms the core workflow for both CAD systems, enabling automatic updates to dependent features whenever parameters or dimensions change. This method is critical when working with internally developed models, ensuring robust design intent and precise associativity.

However, importing external CAD files into any parametric system can be challenging, as imported files typically appear as static (“dumb”) solids without editable feature histories. While desktop CAD software offers some direct editing functions for imported models, Onshape expands significantly on these capabilities.

Onshape offers powerful parametric, feature-based modeling powered by 2D sketching and 3D constructed and applied features such as Loft, Holes, Fillets, and more.

Direct Editing for Imported Geometry in Onshape

Onshape’s direct editing tools are specifically designed to handle imported parts efficiently, empowering engineers to make geometry modifications directly without requiring complex feature reconstruction.

These direct editing tools are especially beneficial for:

• Rapidly editing and updating imported geometry
• Correcting geometry errors caused by file translations
• Preparing vendor-supplied components or library parts for use in parametric assemblies
• Performing post-import adjustments seamlessly within a fully parametric context
• Changing a small quantity of feature selections to adhere to a new definition without separating it from the original feature further upstream in the feature tree.
  

Modification of several fillet faces which were part of a previous feature defined upstream.

Onshape’s Powerful Direct Editing Toolset

Onshape offers extensive direct editing capabilities, all captured as editable parametric features.

1. Modify Fillet

Adjust or remove fillet radii directly, simplifying geometry modifications of imported or native models.

2. Delete Face

Remove or heal unwanted faces, ideal for cleaning overly complex or problematic geometry from imported components.

3. Move Face

Precisely translate or rotate selected faces, enabling easy adjustments and repositioning without complex feature changes.

4. Replace Face

Swap one surface with another seamlessly, ensuring alignment and simplification of imported or existing geometry.

5. Offset Surface

Create offset surfaces from existing geometry, which is useful for clearance adjustments or adding details.

6. Edit Curve (New!)

Intuitively edit imported or native curves, directly modifying their shape and definition with on-screen manipulators. Increase curve order, adjust control points, and fine-tune geometry rapidly. For more on the Edit Curve, head to our YouTube channel.

7. Constrained Surface (New!)

Create a surface from points or mesh data within a specified tolerance, optimizing for performance or smoothness as part of a direct editing workflow for imported parts. Check out this video about Constrained Surface.

Turning "Dumb" Solids into Intelligent, Configurable Components

One of Onshape’s distinctive strengths is how direct edits become fully parametric features within your model history. This allows you to:

• Define parameters or variables for geometry edits, restoring parametric flexibility to imported components.
• Quickly generate multiple configurable variants of formerly static imported geometry.
• Adjust, suppress, or roll back direct edits seamlessly, as with any parametric feature.

Onshape’s direct editing tools enable engineers to rapidly adapt imported, non-native geometry into intelligent, flexible designs without extensive reconstruction or modeling overhead.

Machine Design and Library Parts

Industries such as machine design often rely on imported vendor models and extensive component libraries, typically comprising most design data. Ask yourself, does that data have parametric information in your current library today? Probably not, because it was downloaded from your vendor as a STEP file or similar. However, suppose the need arises for you to edit a vendor component. In that case, Onshape’s enhanced direct editing capabilities streamline working with these components, significantly reducing rework and remodeling time.

Now, your data lives in Onshape and can be accessed by all company members. A Librarian group in your company may be a good idea to manage large amounts of library data. Make sure the entire company can read the data while the Librarian group can edit it, including custom properties like vendor and cost.

Why Onshape’s Direct Editing Matters for CAD Users

Onshape offers experienced CAD users the familiar strength of parametric modeling combined with robust direct editing capabilities that surpass the limitations traditionally encountered with imported models. Engineers transitioning from file-based can confidently leverage Onshape’s direct editing tools to:

• Rapidly adapt imported and legacy CAD data
• Easily generate parametric and configurable designs from previously static geometry
• Simplify complex editing tasks, accelerate design workflows, and enhance team collaboration
  

Take the Next Step

Want to explore Onshape's direct editing firsthand? Visit our Onshape Learning Center for tutorials and courses. Also, check out other helpful Tech Tips for more expert guidance.

New to Onshape? Start a Professional Trial today and experience firsthand how Onshape streamlines imported geometry workflows and boosts your design productivity.