Suppose that you have a project with 5 tasks as is shown in the picture:
Task 3 has a 3-day duration, and will start on Monday, 25.04.2011 and finish on Wednesday, 27.04.2011. What if your task can be done in 3 days but it must (for any reason) be scheduled on Monday 25.04.2011 then Thursday 28.04.2011 and finally on Tuesday, 03.05.2011.? You can make three different tasks but this is not a good idea. A better approach is to split the task. Here is how it’s done:
After you click on Split button move the cursor on the Gantt chart and click on Tuesday, 26.04.2011 and drag the task on Thursday 28.04.2011:
and you will get:
You can see that duration of task 3 is unchanged but the start date and end date was changed for Task 4 and 5 because Task 3 is predecessor of Task 4 and Task 4 is predecessor of Task 5.
Now I will split the same task so the last day is Tuesday 03.05.2011 and I will get:
Again, duration of task 3 is unchanged but the start date and end date was changed for Task 4 and 5 because Task 3 is predecessor of Task 4 and Task 4 is predecessor of Task 5
What if you change your mind? You can “resplit” the task in the same way. Click on the split task back until it is connected again (drag from right to the left):
And the task is joined again.
Remember that a dotted line does not represent duration. Nothing is happening in the dotted line period. If you want to remove dotted line you can do it like this:
and you will get:
You can see that a dotted line is removed. This picture on the Gantt chart is little confusing because you have a task with a 3-day duration that will start on Monday 25.04.2011 and finish on Friday 29.04.2011. Without a dotted line you can think that this is an error, so I strongly suggest: Leave a dotted line in your Gantt chart.