To Place Mate or Flush Constraints in Assemblies

A Mate constraint positions selected components face to face or with the faces flush. The geometry you select is usually a component face, but you can also select curves, planes, edges, or points.

You can place a Mate constraint three ways:

• On the ribbon, use Assemble tab Relationships panel Constrain to place a Mate constraint between two assembly components.
• On the ribbon, use Assemble tab Relationships panel Assemble to place a Mate constraint between two assembly components.
• Hold down ALT while you drag a component into position, automatically placing a Mate constraint.

To begin, place the components to constrain in an assembly file.

To use Constrain to place Mate or Flush constraints

1. On the ribbon, click Assemble tab Relationships panel Constrain .

2. On the Assembly tab, the Type is set to Mate by default. If necessary, click Mate.

3. Select the Predict Offset and Orientation check box if the components are close to the desired position.

   • The offset is the distance between the selected components. The current distance is automatically entered into the Offset field.
   • The orientation sets the Mate or Flush solution. If the components are parallel, and the surface normals are opposite (indicated by arrows), the constraint solution is set to Mate. Otherwise, the constraint solution is set to Flush.

4. Select the first point, curve, face, or work feature. If necessary, click First Selection to enable the selection. Use Select Other to cycle through geometry.

5. Select the geometry to mate to the first. If necessary, click Second Selection to enable the selection. Use Select Other to cycle through geometry.

6. In the Solutions box, select one:

   • Click Mate to constrain geometry face to face (or to make curves, planes, edges, or points coincident).
   • Click Flush to constrain faces or planes to be flush.

7. Enter a different Offset value, as needed.

8. To change the name of the constraint or set limits, click the More button.

   • In the Name box, enter a constraint name, or leave blank and a default name is automatically created.

   • Check Maximum and enter a value to specify the maximum limit position.

   • Check Minimum and enter a value to specify the minimum limit position.

   • Check Use Offset As Resting Position and enter the required value in the Offset value box to specify the resting position.

     Clear the check box to remove limits. Values are retained in an inactive state.

9. If Show Preview is selected, observe the effects of the applied constraint. If either component is adaptive, constraints are not previewed.

10. Do one of the following:

    • Click Apply to continue to place constraints.
    • Click OK to create the constraint and close the dialog box.

To Constrain 2 Axis

Use Opposed and Aligned to control the direction of an axis when creating a mate constraint between 2 axes. These options make it easy for you to get the axes positioned the way you want.

1. On the ribbon, click Assemble tab Relationships panel Constrain .

2. On the Assembly tab, the Type is set to Mate by default. If necessary, click Mate.

3. Select an axis on the component that changes position by default.

4. Select an axis on the component that remains position by default.

5. Make a selection as needed:

   • Opposed (default): Reverses the mate direction of the first selected component.
   • Aligned: Maintains the mate direction of the first selected component.
   • Undirected: Creates an undirected axis constraint on the closest axis.

When placing a mate constraint between 2 axes, Inventor predicts the best match based on the selection with minimal rotation and assigns the optimal selection before displaying the preview.

For example, if you select axis 1 with a direction and then select axis 2, the relative position with minimum rotation is maintained with the type of direction (opposed or aligned) specified. This allows you to add a manual control to prevent the components from orienting incorrectly.

To use Assemble to place Mate or Flush constraints

1. On the ribbon, click Assemble tab Relationships panel Assemble .

2. Select a point, curve, face, or work feature on the component that changes position.

3. Select a point, curve, face, or work feature on the component that remains in position.

4. Enter an offset value, if applicable.

5. Change the solution from Mate to Flush to reverse the direction of the first component.

6. Do one of the following:

   • Click Apply and continue to define constraints.
   • Click OK to create the constraints and exit the Assemble command.
   • Click Undo to delete the selections and continue to define constraints.

To drag a component into position and place a Mate constraint

You can drag a component into position and automatically place a Mate constraint with no offset.

When you drag a cylindrical part over another cylindrical part or hole, the inferred Mate constraint is along the axes. If you position the dragged part over a component face, the system infers a mate between planar faces.

1. Hold down ALT, and then click the component to drag.
2. Drag the component into position. As the dragged component nears the target component, the constraint is previewed.
3. When the component is in the appropriate position, release the mouse to place the mate constraint.

Kinematics mode for translated constraints

If the selected constraint was created with Make Components, you sometimes have the option to select between 2D and 3D Kinematics. See Set kinematics mode in the Make components procedure for more information.

• Temporarily turn off visibility before you place a constraint. Click in the browser to select a component, and then right-click and select Visibility.
• To restrict selectable geometry to a specific part, select Pick Part First in the dialog box, and then click the component you want to constrain. Clear Pick Part First to restore normal selection mode.