Apply the Constraints

Next, we apply fixed boundary conditions to the surfaces of both holes in the vertical part.

1. Click  View Visibility Construction Objects and  View Visibility Construction Vertices to turn off the display of these items.
2. With the  Selection Shape Point or Rectangle and  Selection Select Surfaces commands active...
   1. Click inside the upper hole, near its edge. The circular edge should now be selected. The edges of a 2-D mesh represent surfaces and are selected as surfaces. 
   2. Holding the Ctrl key, click inside the lower hole, near its edge.
3. Click Setup Constraints General Constraint.
   1. Click Fixed.
   2. Click OK.
4. Press ESC to clear the selection. The model displays as shown in the following image.  
   

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