Step 5 : Predecessors.

In reality, the 2 tasks « Saw » and « Sand » can not be performed simustaneously. It should already saw the parts before sanding. We have to create a relation between the 2 tasks to indicate that the "Sand" task can not begin until the " Saw " task is not completed. The "  Saw " task is called a predecessor of " Sand ". To do so :

1/ Double click on « Sand » to open the projects tracking dialog.

2/ Click on the « Predecessors » tab.

3/ Click on the « Add » button, and select the item : « Table/Table top/Saw »

As you can see in the projects tracking window, the start date of the « Sand » task is now egual to the end date of the « Saw » task.

If you want the start date of a task to be temporarily calculated without taking into account predecessors, you can uncheck the "Predecessors" box in the "Project tracking" tab of the "Projects" dialog.