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Fs Links and Critical Path.

3 replies [Last post]
AB Timo
User offline. Last seen 9 years 6 weeks ago. Offline
Joined: 22 Jun 2011
Posts: 108
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Hi all Planners,

The Focus of discussion shall be on the The Topic

 " Always use  Fs Relationship and No Lag"

I was a part of this discussion another forum and was getting different responses,some are as under,

1- Always Use Fs Relationship With no Lag.

2-Always use positive lag with forward pas only and try not to use -ve lag.FS relationship is not necessary (majority oppinion)

3-Use any Relationship (+ve or -ve lag),and  keep in focus the logic only.

 

I agreed with the second point.1st point is also practiceable but not on the large projects where there are thousands of activities and if you split them into further smaller steps to use"FS" Relationship,it will make the plan over crowded.

Secondly if We only use FS relationship the it means that all activities will be critical?? Does it represent a True Scenario??

Any Comments on this topic are wellcomed,

Regards.

AB.

Replies

AB Timo
User offline. Last seen 9 years 6 weeks ago. Offline
Joined: 22 Jun 2011
Posts: 108
Groups: None

Gary,

Thank you I just Found the Thread that Mike Mentioned.I think it has all answers that i wanted.

 

Regards,

Gary Whitehead
User offline. Last seen 4 years 46 weeks ago. Offline

AB,

This has been discussed many time s before as Mike says, and the thread he suggests you look at was probably the most in-depth discussion on it

 

Briefly, I think you should use FS(0) relationships wherever possible, but feel there are times when other relationship types are more appropriate -not becuase the plan gets too overcrowded when you split tasks down into smaller elements requried for FS, but because it can sometimes be difficult / impossible to define / measure precisely where the split should be.

I have never found a good reason to use negative lag.

 

Your second point "if We only use FS relationship the it means that all activities will be critical?? " Is quite wrong.

-All activities would only be critical if you had a project whereby every activity only had 1 sucessor and 1 predecessor. This is never the case.

Your comments suggests to me you have never tried to build a schedule using only FS links -I think you would get a much stronger insight as to which approach is better by giving it a go yourself, than merely posting on the forum. I'd certainly suggest trying it out at least once before deciding it was not the best way.

 

 

Cheers,

 

G

Mike Testro
User offline. Last seen 5 weeks 4 days ago. Offline
Joined: 14 Dec 2005
Posts: 4418

Hi AB

My maxim is that every task should have at least 1 predecessor and at least one successor.

Every link should be FS and the only time to use a lead lag is to allow for curing / drying out periods (set to calendar days)

You will find this expressed in many forum in PP - check out the thread on "Ban these planning abominations".

I have no intention in taking part in another similar debate.

Best regards

Mike Testro