Subtract Tool: Performing a subtraction

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Performing a subtraction

A subtraction refers to the merging of overlapping geometry from one group or component with the geometry from a second group or component (the overlapping geometry is merged with the first selected group or component). The first group or component is then removed from the result. A subtraction can only be performed on two overlapping groups or components. The resulting subtraction also depends on the order the groups or components are selected. Activate the Subtract 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 subtraction:

  1. Select the Subtract 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 one 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. The following image shows the right group selected:

  4. Click on the second group or component. The resulting geometry remains.

Selecting the left group first would yield the following result:

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

Performing a subtraction by preselecting groups or components

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

  1. Select the Select tool (Select Tool). The cursor changes to an arrow.
  2. Select two overlapping 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 > Subtract. The first group or component remains with the subtraction of the second merged. The following image shows the result when the left group was selected first:

Selecting the right group first would yield the following result: