Importing and Editing a Part

The estimated time of completion is 8 minutes

Occasionally, you might have a part or assembly from another system that you want to import into Onshape. Onshape allows the import of files from many systems, but note that when moving between any CAD system, the models lose their parametric history. However, Onshape supplies powerful direct editing tools so you can still modify parts after importing them into the system.

This lesson covers how to import a part from another CAD system and modify it with Onshape's robust direct editing tools.

Best import format

You can import many types of files into Onshape, but if you want to edit the part, the most reliable neutral 3D CAD file format to import into Onshape is Parasolid (.x_t). If the system the file originates in does not support Parasolid, STEP (.step or .stp) is the next best format.

Choosing where to import in Onshape

There are two options in the Onshape interface for importing a file, each with a different workflow.

Import from the Documents page Create > Import action to create a new Onshape document for the imported data.
Import from within an Onshape document, to import the files into that open Onshape document.

Option 1: Create a new document for each file imported

To create a new Onshape document to contain your imported data, import from the Documents page:

Click the Create button on the Documents page:
Select Import files... from the menu.
Select one or many files, each file results in a new Onshape document created.
Click OK when satisfied with your selection.
In the Import dialog that appears, choose one of the following, keeping in mind that your choice applies to all the files you selected:
- Import to a single document (per file you select)
- Split into multiple documents (split assemblies and parts into different documents, preserving structure - again, per file you select)
- Combine to a single Part Studio (combine assemblies to Part Studios only (best for small assemblies - per file selected)
Choose appropriate options:
- Orient imported models with Y Axis Up - If the models in the file being imported are in this position (e.g. SOLIDWORKS or Inventor files), and this box is checked, they will remain in this position in Onshape. Onshape's up axis is the Z axis. (This option is not available when splitting one file into multiple documents.)
Click OK to begin import.

The files are uploaded in sequence and translation of the data happens in the background. You can continue working in Onshape during this process. Notifications are posted when processes have finished. Notice that you have one new Onshape document for each file that you imported, unless you selected to split assemblies and parts into multiple documents, then you may have more than one file per imported document.

Option 2: Import into an existing document

To import one or more files into an existing Onshape document (with no new document creation):

Open the Onshape document into which you want to import files.
Click (Insert new element icon) at the bottom of the window.
Select Import... from the menu.
Select one or more files to import and click Open.
Select the preferred import option:
- Import to this document - Import the parts to one Part Studio and the assemblies (in each file) to their own Part Studio (per file) and Assembly tabs/per assembly/file. The parts will not be recreated for all the assemblies, but will live in the Part Studio and be instanced into the relevant assemblies.
- Combine to a single Part Studio - Combine the assemblies and parts in the imported file to a single Part Studio in this open document. This is done per file selected and is best suited for small assemblies only.
- Orient imported models with Y Axis Up - If the models in the file being imported are in this position, and this box is checked, they will remain in this position in Onshape. Onshape's up axis is the Z axis. (This option is not available when splitting one file into multiple documents.)

The files are uploaded in sequence and translation happens in the background. You can continue working in Onshape during this process. Notifications are posted when processes have finished. Notice that the document now has a new tab for each file that you imported.

Where is the imported data?

All uploaded files appear either as individual documents in the Created by me filter on the Documents page or within the document into which they were imported.

Regardless of which import method you used, the Onshape documents containing the imported data have a tab with the original file, and then also Part Studios and any other tabs necessary (Assemblies, for instance) to store the parts and assemblies translated from the original file.

Updating imported data

If you are still working on the original file within the original system, and want to update the file as it exists in Onshape, you can. To update the data imported into Onshape:

Export the file again from the original system. Note the file name and location.
Open the Onshape document containing the originally imported data, right-click the tab with the file name, and select Update.
The name of the Onshape tab is not changed (even if the file chosen for the update has a different name). The data is reloaded and re-translated into Onshape.

Editing a part with direct editing tools

Onshape offers a variety of tools for editing parts with parametric histories, but sometimes imported parts do not come into Onshape with their history. In these instances, Onshape's direct editing tools come in handy:

Modify fillet - Change the radius of a fillet or remove existing fillets