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Hammock Task

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AB Timo
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If hammock is an activity that is derived by two activities i,e start Date of Hammock is Derived by its Predecessor and finish Date by its successor. ie,

Predessor -->SS-->Hammock-->FF-->Successor

Then Can we say that Generally Every activity having Predessor and Successor is "Hammock"   ????

 

Regards,

 

Faiz

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AB Timo
User offline. Last seen 9 years 6 weeks ago. Offline
Joined: 22 Jun 2011
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Hi Gary,

I Use Primaver p6. In "activity Type",if you see there is no such type as "hammock". But from your definition I was just thinking that "Level Of Effort" activity can be Called as hammock?

 

Mike,Thanks to you also For Clearing the Concept.

Regards

Gary Whitehead
User offline. Last seen 4 years 47 weeks ago. Offline

"If hammock is an activity that is derived by two activities i,e start Date of Hammock is Derived by its Predecessor and finish Date by its successor. ie,

Predessor -->SS-->Hammock-->FF-->Successor

Then Can we say that Generally Every activity having Predessor and Successor is "Hammock"   ????"

 

Faiz,

The difference between a hammock and a normal activity is that the hammock's finish date is dervied from it's successor, whereas a normal activity's finish date would be dervied from it's start date plus it's duration

This means that the duration of a hammock activity is not entered by the planner -it is calculated autoamtically and changes as the predecessor and successor move in time -the hammock automatically streches or contracts so that it covers the period between it's successor and predcessor

 

Mike Testro
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Joined: 14 Dec 2005
Posts: 4418

Hi Faiz

It is possible that your software does not allow the creation of a true hammock task bar.

Remember that a "hammock" is just what it says - a task whos duration is "slung" between the start and end dates of a selection of live tasks - it is a summary outside the live programme that shows what is happening inside.

Say for instance that you wanted to create a hammock that encompasses all the rebar trades in your project.

In asta power project you would simply set up a hammock task by coverting a normal task to a hammock.

Then filter on all rebar trades and ticking the Add to Hammock command and your hammock is created.

The long way round is the create a subchart with twice the number of milestones as there are rebar trades and then lnik FS upwards from the start and end of each rebar task to the respective milestone.

Then sumarise the milestones.

Now as your rebar tasks move by way of delay or progress then your hammock will reflect the changes.

Best regards

Mike Testro

AB Timo
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Joined: 22 Jun 2011
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Hi Mike,

You say,

"A true hammock takes two or more tasks in a programme and shows the actual start of the earliest and the actual completion of the latest"

If I did't get it Wrong, the hammock task will define the eactual start of the Predecessor and actual Finish Of the Successor..Right?? and then you say,

"The hammock bar will move as the actual programme tasks move"

It means if Predecessor/Successor tasks move hammock will move.Then how can it define the actual start and finish when it is moving with programe tasks.

Mike, to me these two statements are in contradiction to each other.May be i am not getting it.

 

Best Regards,

Mike Testro
User offline. Last seen 5 weeks 6 days ago. Offline
Joined: 14 Dec 2005
Posts: 4418

Hi Faiz

No.

A true hammock takes two or more tasks in a programme and shows the actual start of the earliest and the actual completion of the latest.

The hammock bar will move as the actual programme tasks move.

They can be useful for predicting the planned start of a trade package for design and procurement or the planned end for test and commissioning.

Most software will allow the creation of hammocks within the software - but beware of manually changing the hammock tasks as the actual tasks will be changed also.

Best regards

Mike Testro