Help me please! Groups and Critical Path

[swell estimator]

Nobody has responded to my questions since yesterday and I have a schedule
due tomorrow! Please reply!

In the Tracking Gantt view; selecting 'critical' under "Groups" all my 149
tasks show under Critical: 'No'

The only thing that shows as Critical: 'Yes' is the deadline milestone I set
5 days after the end of the last task.

What is going on? - I'm lost. Can I send my schedule to you (3rd request
today.)

3-straight-16-hour days - I tried everything others have suggested and I'm
back to square 1. It's not that others aren't trying to help - they are, but
nothing's working. It's very discouraging.

 

[Dale Howard [MVP]]

swell --

In Microsoft Project, the Critical Path is the series of tasks that have 0
days of Total Slack. Total Slack is the amount of time a task can be
delayed without impacting the Finish date of the entire project. I like to
think of Total Slack as the amount of time for things to go wrong in a
project. To see the amount of Total Slack on each task, you can apply any
task View, such as the Gantt Chart view and then click View - Table -
Schedule. Pull the split bar to the right so you can see the Total Slack
column on the right side of the Table.

From your description, it sounds like you added a Milestone 5 days after the
Finish date of the final task, which added 5 days of Total Slack to every
task in your project. This is why you only see the one task as Critical.
There's a trick you can use, however, that will allow you to change the
definition of the Critical Path. Click Tools - Options - Calculation. At
the bottom of the dialog, change the "Tasks are critical if..." definition
from 0 days to at least 5 days, and you will miraculously see a new Critical
Path.

Just a thought. Hope this helps.

 

[Jim Aksel]

Swell - I beg to differ. Both Jan and I offered to review your schedule if
you e-mailed it to either of us. Nothing has been received. Sorry, I an
unable to assist on Firday 24 OCT 2008, I am in route to Phoenix, AZ, USA.

Might I sugest you search the help for the following terms:

Total Slack: the amount of time a task's finish date can be delayed without
delaying the project's finish date.

Free Slack: the amount of time that a task can be delayed without delaying
any successor tasks. If the task has no successors, free slack is the amount
of time that a task can be delayed without delaying the entire project's
finish date.

Start Slack: the duration between the Early Start and Late Start dates. The
smaller of the start slack and finish slack amounts determines the amount of
free slack available, that is, the amount of time a task can be delayed
without affecting the start date of a successor task or the project finish
date.

Finish Slack: the duration between the Early Finish and Late Finish dates.
The smaller of the finish slack and start slack amounts determines the amount
of free slack available, that is, the amount of time a task can be delayed
without affecting the start date of a successor task or the project finish
date.

For any of this to make sense, it is assumed your file has successors on
evey detail (non-summary) task that are FS to some other task. Those that do
not have a logical successor are tied to a finish milestone as FS. I also
assunme all non-summary tasks have a FS pred.

We are truly here to help. Please post back.

Jim Aksel, MVP
Check out my blog for more information:
http://www.msprojectblog.com

 

[Jack Dahlgren MVP]

Swell,

Adding the deadline milestone 5 days after the last task SHOULD make all of
the other tasks non-critical.

A task is "Critical" if it can not slip without affecting the project finish
date.

By putting a 5 day gap between the last task and your milestone you have
made it possible for every task (except the milestone) to slip by 5 days
before the milestone is pushed later in time.

You can fix this by putting the milestone 5 days earlier, or putting a 5 day
task between the last task and the milestone (link it with dependencies) or
by adding a 5 day lag to the dependency between the last task and the final
milestone.

The easiest way to see where you have critical path problems is the "Total
Slack" column. Insert that column in the view. Wherever the value is 0, the
task will be critical. You can not edit the value of total slack. It is
calculated on the basis of the schedule logic. You must have proper
dependencies between tasks to have a critical path.

-Jack Dahlgren

 

[swell estimator]

Jim and Jan and Others:

First let me apologize for letting my tiredness and anxiety over an
encroaching deadline get in the way of good judgment. Online support from
the MS community is an extremely valuable service and what’s more there’s no
charge for it, there’s no service contract required.

I posted several different questions even tho I was admonished not to do so
as it prevented members from following the thread. This made sense but I
needed replies quickly and I wasn’t getting them unless I posted a new
question. This discontinuity for which I was responsible for was why you
missed one of my posts in which I explained that 2 people “kindly offered me
to send them my schedules†– referring to you and Jim - “but I had missed
their deadlines because of trying things others had suggestedâ€.

I very much appreciate all the help that you and others have given me. Are
there any things to do, a privilege that should not be exercised too often,
when one needs a quick response?

Here is where I stand today. After removing the milestone/deadline 5 days
after last activity I made the last activity the deadline and adding more
predecessors, I came up with a feeble critical path, feeble in the sense that
only 8 of my 152 tasks showed up in red on the tasks table and Gantt chart.
I’m confused by this. Isn’t there at least one critical path, an unbroken
line for the critical path from the beginning to the end no matter how the
schedule is put together? In my latest S, the 8 cp tasks are preceded by
numerous gaps both fore and aft.

After I insert the slack column a large amt of slack shows up for many
tasks. I’m planning to go back and make sure I added predecessors and
successors as much as possible. Is that the right to do?

I'm going to send you and Jan my schedule. Thanks so much - Swell

 

[Dave]

Counter-intuitive results can come from a levelled plan.

Try the following:

Make a new plan with 3 activities, each of 5 days. Join them all to a
start milestone and end milestone. There are no linkages between the
tasks themselves. Assign a resource to those tasks at 100%.

Now if you show the critical path, all three tasks will be critical (and
as it turns out the resource will be seriously overallocated).

Now level, and you will find that the last task is the only one
displayed as critical.

If on the other hand, the activities were linked such that the linkage
respected the levelled order, then all tasks would be on the critical path.