For example, during mechanical design, we often need to change the position as well as the dimension of the keyway. In this section, we will add Linear stretch function for the keyway on the step shaft.

2. Add Stretch Action: 

Click stretch action button on action panel, choose parameter according to prompt and define right grip as key parameter point, as shown in below picture.

Blacken object is the operational object of the action, broken line frame is the stretch frame, objects intersect with stretch frame will be stretched, objects which be selected by stretch frame will move.

3. Test Dynamic Block: 

Exit from block editor, drag stretch grip to stretch the keyway, as shown in below picture.