Resource levelling question

[Des]

I asked this question yesterday in another group, but I
did not explain my problem fully.

I am trying to schedule a project having large necessary
lags between activities.When you set the required lag,you
effectively tie each activity to the chosen lag. Even if
you move one activity, you move them all,because the lag
is not seen to give any free slack to any activity.

In this project there are over 150 activities, so it
seems impossible to level the demand for resources.

My question then is to ask you if there is anyway that
the lag between individual activities can be treated as
free slack, thus allowing the activities to be moved
individually in an attempt to level the demand for
resources.

Thank you

Des.

 

[Mike Glen]

Hi Des,

Welcome to this Microsoft Project newsgroup

The simple answer is not to use lag. I suspect you're using lag to drive
the start of the next task to meet some chosen date. If you do this,
Project loses all its flexibility, because, as you have observed, lag is
part of the logic that says the successor task cannot start until 10 days
have passed (for example using a FS link with 10 days lag). If you're
applying lag to allow for resources to become available, then you are doing
Project's job - you need to enter resource availability as a contour and/or
a resource calendar. Then, if you let Project do what it was designed for,
you remove the lags and level, Project will tell you what is possible.

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

 

[Guest]

Thanks Glen
My problem is more like this:
I have several activities scheduled say 6 weeks apart.
But this 6 weeks delay can be changed if it is necessary
to avoid over allocation, or under utilization of
resources.
So, I need the facility to schedule these activities at 6
week delay with some built in slack. We can vary the
timing around the 6 week delay.
Hope this helps describe the requirement

Thanks very much
Des.

 

[Mike Glen]

OK Des, I still suggest you remove the lag, level and see what you get -
you should get no overallocation to worry about. However, you could then
tweak the project to get what you want. I would tweak the first occasion by
giving a start no earlier than constraint on the appropriate date and then
re-level. Continue until it meets your needs.

Mike Glen
MS Project MVP

 

[Steve House]

Lag times generally indicate mandatory delays, not optional ones. Freshly
poured concrete takes 48 hours to harden enough to finish, for example. If
that's true, it'll take 48 hours from the time it's poured regardless of
whether we pour it on a Monday or on a Friday. I wonder if what you're
calling a necessary lag really is necessary? What process is it that drives
the need for the lag times?