Pre-Task

[Ed]

Hello everyone, I am recently starting to get involved with Project, and
there is something I can't figure out how to do and I am not sure if it is
possible. There are some tasks which have a Predecessor task which is not
linked to any other.

For example the case where I would have to build a "Concrete Floor-Slab",
and after I have it ready I can put "Marble Floor" in it, the building
sequence is Concrete floor-slab and then Marble Floor with a FS relationship,
but I would like to have a "Pre-task" for Marble Floor, which is "Ordering"
it, and that task has a Duration of 4 weeks, so to be able to start with
Marble Floor, I would need to be done with Concrete Floor-slab, and Ordering,
but Ordering task has no predecessor, I just need to do it 4 weeks before
starting Marble Floors.

What I have done so far is just to put "Ordering" with a FS relationship to
Marble Floors, and just manually move it have the Finish date when "Marble
Foor" starts, the problem is when other activities change Marble Floor moves
forward or backward in time, and Ordering stays still. That is because
Ordering is taken as a activity that needs to start n day, is there a way to
do it the other way around? I mean to "anchor" the Finish date of Ordering to
the Start of Marblefloors and have the Start of Ordering varying?

The whole idea is to be able to incorporate to my program, the "Ordering" or
"Pre-fab" times for some special activities, for the construction to be able
to run smoothly.

I hope I was able to explain myself!

thanks in advance,

Ed

 

[Jan De Messemaeker]

Hi,

Microsoft and many specialists will recommend you to make a Start to Finish
relationship from Marble Floors to Ordering.
That works fine as long as we talk plan data. The only problem is that,
should ordering for any reason happen late, Marble Floor will still stay at
the same date.

So it is a solution but only a half-hearted one.
Project is unable to completely simulate Just in Time processes, Sorry :-((

 

[Steve House]

Secondig Jan's comments, also. ... ordering should not be a 4 week task.
The duration of the task is how long you would be able to actually see
physical activity if you were watching someone do it. The duration of
"ordering" is how long it takes someone to look up the items in the
catalog and place the phone call, maybe a couple of hours. Then you
have a 4 week LAG time will waiting for the order to arrive. But the
person who did the order isn't tied up waiting for the order to arrive
unable to do something else - they can do other things while they wait -
and that should not be included in the task's duration.