A critical dimension is a specific part dimension, which must meet the defined tolerances. A critical dimension is defined by the distance between two specified nodes, and is used to study part shrinkage and warpage.
Click (Boundary Conditions tab > Dimensions panel > Critical Dimensions) and select Optimization from the drop-down menu.
Type the ID of a node that defines one end of the critical dimension. Alternatively, click on the node on your model and the ID will be placed in the Node 1 box automatically.
Repeat the process for the second node.
Type a name in the Name box that is unique to this study.
Click Close to close the dialog.
Click Finish Boundary Conditions to close the Boundary Conditions tab.