Union Tool: Performing a union

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Performing a union

A union is the merging of two or more solid volumes into a single solid volume.

The result of a union is similar to the result of an outer shell. However, the result of a union can contain internal geometry whereas an outer shell can only contain external faces.

The following image shows two square tubes on the left, a union of the tubes in the center, and an outer shell of the tubes on the right:

Activate the Union tool from the tool palette (Mac OS X), the Solid Tools toolbar (Microsoft Windows) or the Tools > Solid Tools menu.

The following image shows two groups:

The following image shows these two groups when they overlap:

The following image shows the overlapping geometry of these two groups using X-Ray mode:

To perform a union:

  1. Select the Union tool (). The cursor changes to an arrow with a circle and a slash () if you are not over a group or component or a arrow with the number 1 () if you are over a group or component.
  2. Move the cursor over on of the groups or components. The cursor changes to an arrow with the number 1 ().
  3. Click on the group or component. The first group or component is selected.
  4. Click on the second group or component. The resulting union of the geometry remains.

Note: Solid tools will only operate on geometry that has watertight volume (no holes).

Performing a union by preselecting groups or components

You can also preselect the groups or components before performing a union. To preselect groups and components and perform a union:

  1. Select the Select tool (Select Tool). The cursor changes to an arrow.
  2. Select all of the intersecting groups or components. The selected entities are highlighted in blue.
  3. Context-Click on one groups or components. The context-menu appears.
  4. Select Solid Tools > Union. The union of the components or groups remains.