Linking the First Piston Link the first piston to the upper arm. The piston mechanisms are no longer nested blocks. Each piston and its accompanying cylinder are separate blocks with a relation. Right-click Sketch1 and click Edit Sketch . Drag Piston-1 adjacent to Upper Arm-1, and then click in the graphics area to clear the selection. Click Rebuild (Standard toolbar). Click Zoom to Area (View toolbar), and zoom in to Piston-1. Clear the view tool, and then select the centers of the arcs for Selected Entities. In the PropertyManager, under Add Relations, select Coincident , then click . Parent topicSketch Blocks Previous topic Exploding Blocks Next topic Linking the First Cylinder