About the Flat Pattern Preview Window
Use the Flat Pattern Preview tool to open a window with a preview of the sheet metal body in an unbent state. The preview is closed when you add or redefine features in a design. The Preview window is available in Verify mode when creating or redefining most features.
To access the Flat Pattern Preview tool, click 
on the Graphics toolbar or mini toolbar. The Flat Pattern Preview window displays one sheet metal body with geometry. The default body to display is selected in the following order:
on the Graphics toolbar or mini toolbar. The Flat Pattern Preview window displays one sheet metal body with geometry. The default body to display is selected in the following order:1. The selected sheet metal body.
2. The active sheet metal body, when a body is not selected.
3. The first sheet metal body in the part, when the active body is a solid body.
These additional commands appear on the Graphics toolbar of the Flat Pattern Preview window:
• 
—Click to display the following options:
—Click to display the following options:◦ Unfold bends added to forms—Unbends geometry that was added to a form that is not part of the original form.
◦ Flatten Forms—Flattens the geometry of forms.
◦ Project cuts added to forms—Projects cuts and holes added to form geometry to sheet metal placement surfaces.
• Overlapping Geometry—Toggles the display of overlapping geometry. (default)
Overlapping Geometry—Toggles the display of overlapping geometry. (default)• 
Bounding Box Dimensions—Toggles the display of the length and width dimensions of the unbent sheet metal part. The dimensions are associated with the SMT_FLAT_PATTERN_LENGTH and SMT_FLAT_PATTERN_WIDTH parameters.
Bounding Box Dimensions—Toggles the display of the length and width dimensions of the unbent sheet metal part. The dimensions are associated with the SMT_FLAT_PATTERN_LENGTH and SMT_FLAT_PATTERN_WIDTH parameters.• 
Create Instance—Opens the New Instance dialog box to automatically create a flat or bent instance.
Create Instance—Opens the New Instance dialog box to automatically create a flat or bent instance.• 
Create Representation—Opens the Flat Representation dialog box to automatically create a flat or bent representation.
Create Representation—Opens the Flat Representation dialog box to automatically create a flat or bent representation.Keep in mind the following points when using the Flat Pattern Preview tool:
• Set the accessory_window_display configuration option to yes to open the preview in a docked window, or set it to no to open the preview separately.
• A preview does not appear for bodies with the following geometry:
◦ Two or more disjoint volumes
◦ Unmerged quilts
◦ One or more deformation areas that cannot be unbent
◦ Relief geometry that is not valid
◦ Hem geometry that is not valid
◦ Deformation areas that cannot be regenerated
◦ Sharp edges that cannot be unbent
◦ Surfaces that cannot be unbent
• Geometry that cannot be unbent is highlighted in a different color. To change the default color, click > 
Options > . Expand the Graphics branch and specify the required color for Secondary previewed geometry.
Options > . Expand the Graphics branch and specify the required color for Secondary previewed geometry.