# Import a CAD File


Parts and Custom Sheets require a CAD file to define their boundaries. You can import files from popular CAD file formats using the Import CAD File action.

The Import CAD File action can be accessed from these detail views:

From any of these detail views, the Home ribbon tab and the File ribbon group will feature the Import CAD File action.

The action will show an open file dialog allowing you to select a CAD file in one of the supported file formats.

With certain legacy file formats (DXF, for example), there is no unit system defined in the file. To ensure the integrity of the CAD file, you will be prompted to select the unit system in which the file was saved in.

The Choose File Unit System dialog

Item Name Description
Overall Dimensions The measured overall dimensions of all the geometry in that file.
File Unit System Select in which units the file was saved in.
Preview This shows a preview of what the imported geometry scaled to your preferred units would measure. For example, you import file_in_inches.dxf, but your preferred units are centimeters. The overall dimensions are 1 × 1 × 0 (a one inch per one inch square). You select Inches in the File Unit System drop down knowing the file was saved in inches. Since your distance units are centimeters, the preview would show a square measuring 2.54 cm × 2.54 cm confirming the correct scale.
OK Confirm the selected unit system, close the dialog and import the CAD file.
Cancel Cancel the file import and close the dialog.