Microsoft Project 2010 - Linking Activities

Grumpy_chap

Hello,

I hope someone can assist with a task I have been asked to "force" in a project gantt chart created within Project 2010.
It requires a task duration to be subordinate to the dependencies.
It may not be possible - in which case, at least verifying that would be a conclusion of sorts.

Task 1 start 20/01/2025.  Duration 5 days.  Finish 24/01/2025.
Task 2 start at end of task 1, 27/01/2025.  Duration 5 days.  Finish 31/01/2025.
That bit is simple and straight forward.

Task 3 start at end of task 1, also 27/01/2025.
Task 3 finish 5 days after end of task 2, so 07/02/2025.
If Task 2 takes 10 days, then duration of task 3 automatically increases so the end is still 5 days after (now 14/02/2025) but the start date of task 3 remains at 27/01/2025.

I don't think Project has functionality for dependencies to force duration.

Anyone who can assist will be greatly appreciated.

tacpot12

I think you will find the answer in this video: https://youtu.be/TyQLuzvQhrQ?si=OxxhGTmrkEG9_CB2

Grumpy_chap

Thank you, but that video does not cover what I am seeking which is a task constrained by the start and the finish set by other tasks but with the duration changing accordingly.

I can create a gantt that looks correct and shows the links as required:

Task 4 starts when task 1 ends.
Task 4 finishes 5 days after task 3 ends.
Task 5 starts when task 4 ends.
The links show accordingly.

It works graphically.
It is not a functional linkage as it is forced by the entered duration for task 4.

Let's say that task 2 will now take 8 days (instead of 5).
Task 3 will be later.
The task 4 needs the duration to automatically extend (also by 3 days) so that it still starts at the same time as task 2 and still ends 5 days after task 3.
Task 5 will then start and end 3 days later.

If the logic works, that should mean I just change the duration of task 2 and everything else changes.
But you can see it does not, the duration of task 4 remains the same and it does not start until after a lag from task 1


I can, of course manually change the duration of task 4 also to make it look correct:


But that is not getting a functioning programme with automated task adjusting the duration of task 4 to match the constraints.

I think this is a functionality that is possible in P6.
I don't have P6, I only have Project.

Desmond_Hume

It's reading like your task 4 in the above example is actually a level of effort, rather than a defined task? Which is where P6 would help, as you've said. 

From memory, MSP doesn't have LoE task functionality but, I'm 99% sure you can hack it.  I'll rack my brains to think but in the mean time, Google MS Project Level of Effort.

I'm no fan of lags in schedules really. They're often missed. Better practice would be a SVT.  Depending on schedule complexity I guess. 

Grumpy_chap

Desmond_Hume said:

It's reading like your task 4 in the above example is actually a level of effort, rather than a defined task? Which is where P6 would help, as you've said. 

From memory, MSP doesn't have LoE task functionality but, I'm 99% sure you can hack it.  I'll rack my brains to think but in the mean time, Google MS Project Level of Effort.

I'm no fan of lags in schedules really. They're often missed. Better practice would be a SVT.  Depending on schedule complexity I guess. 

Thanks.

I am thinking of something that "might" work but will look wrong still.

What's an SVT?

Desmond_Hume

Grumpy_chap said:

Desmond_Hume said:

It's reading like your task 4 in the above example is actually a level of effort, rather than a defined task? Which is where P6 would help, as you've said. 

From memory, MSP doesn't have LoE task functionality but, I'm 99% sure you can hack it.  I'll rack my brains to think but in the mean time, Google MS Project Level of Effort.

I'm no fan of lags in schedules really. They're often missed. Better practice would be a SVT.  Depending on schedule complexity I guess. 

Thanks.

I am thinking of something that "might" work but will look wrong still.

What's an SVT?

Schedule Visible Task. Instead of using a lag (that's hidden and can be missed) you create a dummy task in the schedule to show "something" happening where the lag is. Be that concrete curing, sub-con work etc. 

Heedtheadvice

This is something that can be done using VBA in Project. ( I have not read all the thread detail so might be well out of order!!)

If you are familiar with VBA then have a look at https://stackoverflow.com/questions/3828082/assigning-task-duration-to-an-already-added-task-in-vba-microsoft-project .

That will not provide you with an answer but will give indications of what can be done. A Search for setting task durations on the net by vba in Project might well give you a near solution.

You might devide task 3 into two parts such as task start activities and task completion activities but that is probably only pertinent if task 3 has activities dependent upon task 2 completion rather than a need to just stretch task 3 to remove work rate constraints or similar.

Grumpy_chap

Thank you all for your advice.

I have found a way that seems to work. 

• Create a sub-task and link for the start of the event.
• Create a sub-task and link for the end of the event.
• Change the format of the single "roll up" task to look like a standard task.
• Roll up the sub tasks.

I also tried the LoE way of doing it.  That sort of works but, for some reason results in the incorrect end date.  It may be that I made an error that is not obvious.  I think this is probably the better way than the sub-task approach, but the sub-task approach will get me over the hurdle I need to cross.  Learning how to correctly work LoE is for another day when I have more time.


I have not tried the VBA approach as I am not familiar with VBA so it might be beyond my skillset.


For reference, here is the screenshot of my outcome (note - I added a check roll up task to verify that changing the format of my task 4 roll up task does not reset for all roll up tasks):


Thank you everyone for the advice and suggestions - it seems as though the power of the hive mind has achieved success

DullGreyGuy

Was always one of the pains of MS Project and why as a Mac user I'm not sad that they haven't ported it to MacOS. 

With my preferred alternative you would tell it the work effort for task 4, put in your constraints and you then have options over if you start as early as possible, as late as possible or stretch the lapsed time. Whilst it can export to XML that Project can consume when back in Project it stops working again. Only way I ever found was to bodge it with two tasks as you've done or manually adjust it