move linked tasks together without setting lag time

[kennyb]

Is there anyway to move tasks together if the predecessor
moves? Not all tasks start immeidately after it's
predecessor. My project has numerous tasks in it and to
go through it to set the lag time for each one would be
immensly time consuming. What I'm trying to do is if
there is a delay in the project and I move a task to
reflect the delay, I want every task after to move
accordingly.

 

[John]

Kenny,
It sounds like you are asking for two opposing things. Not all tasks
start after their predecessor yet if there is a delay you want every
tasks to move accordingly. What about the slack time (i.e. float)
between the predecessor and its delayed successor? That's the main
reason slack time is desirable - it gives "schedule breathing room".

There are three ways I can think of to do what you want. One is to
manually put lag into the predecessors and yes, that is tedious. It will
move all tasks in unison if something "up the chain" is delayed.

A second method that I hesitate to mention is to go ahead a put a normal
Finish-to-start predecessor on the delayed task. Then put a
"start-no-earlier" constraint on the successor task. This method differs
from the first method in that successor tasks will not move even though
a task up the chain is delayed - that is until the predecessor pushes
the successor beyond the constraint date. The reason I hesitate to give
this solution is that it is not good practice and it is likely to cause
problems when analyzing the plan's logic flow (e.g. critical path
analysis). It is also tedious to insert the necessary constraint dates.

A third method is to write a VBA macro that automatically delays certain
tasks. The heart of the macro is an algorithm that adjusts task start
dates based on a set of criteria. For example, say that certain tasks
must always start on a Monday even though their predecessor task
finished in the middle of the previous week.

Hope this helps.
John

 

[Mike Glen]

Hi Kenny,

Welcome to this Microsoft Project newsgroup

That's what Project is designed to do! Reading between your lines, I
suspect that you have typed in dates into tasks, which is not a good idea as
that is what Project does so well: ie calculate the dates and create an
acceptable schedule for you. Every time you enter a date (or move a bar on
the Gantt chart) Project will assume that's what you want and puts in a
Start No Earlier Than constraint. These constraints will affect the
flexibility of your project and produce the results you're experiencing.
No - the best way to use Porlect is enter Tasks, enter Durations and enter
the Precedence (logic) links (with lag as necessary) and then leave Project
to do what it's best at - calculating the dates. Had you done that and put
in the appropriate lags that you needed, then you would not be posting here!
Sorry but your only sensible way out is to remove all the constraints
and enter in the correct lag figures.

FAQs, companion products and other useful Project information can be seen at
this web address: <http://www.mvps.org/project/>

Hope this helps - please let us know how you get on )

Mike Glen
MS Project MVP

 

[JulieD]

Hi Kenny

one of the reasons that we "link" tasks is precisely for this situation, if
something changes to a predecessor the effect of the change is distributed
"automatically" through the project and while it might be time consuming to
set up a project correctly in the begining with relationships / leads & lags
it certainly saves a lot of work trying to ensure that everytime something
changes you remember to change all of the associated information.

so if you haven't linked your tasks then i would recommend that you do so.
I recently re-evaluated and re-linked an entire project of 350+ tasks and
although it wasn't a straight-forward project it took less than a day to do,
now i (& more importantly, the client) know that we have good base to work
from and the day certainly wasn't wasted - we identified a lot of "mistakes"
& ommissions due to the ad hoc nature of the process up to this point.

however, if you're going to stick with what you've got then the only
suggestion i can make is to use the levelling delay column to enter a
"delay" for all tasks.

Cheers
JulieD