Warning - When you delete the 'element' you will also delete these elements.
Many elements are 'dependent on' [need] other elements.
A Pin-Joint, when you add a Pin-Joint, you must click a Point in two different Parts.
Thus, the Pin-Joint is dependent on' the two Points.
If you delete one the two Parts, MechDesigner must also delete the Pin-Joint.
The Dependent Elements dialog-box warns that you will delete 'dependent' element if you continue.
- OR -