SCHEDULING WITH CONSTRAINTS

Hi Raphael



It was youre thread.



We have Raphael and Rafael. - I spelt the wrong one.



Best regards



Mike Testro

Mike

In your response, were you referring to me Raphael or the other Rafael in Puerto Rico



By PP I meant Planning Planet



I have just looked back at few of my recent posts, I think I going to work down your path ....



Raf

I Have a Custom Tool Buttom With a macro which makes all activities constraint type as "as soon as possible "

i press this button every now and then, MSP is a wonderful software to make massive initial plans , make plan just import to P6 or from there export to P3



i make all my plans in MSP ( average 5000 Activities) and run in P X

Hi Raphael



It is not much of a consolation but there are programmes out there which are much worse than PP.



Project Commander - Fastrak - powerproject lite to name a few.



Best regards



Mike Testro.

Folks



Goodness me



It is time people learned to plan without the need to force an answer.



I almost NEVER use constraints, I have a contract which is full of them and thats where they belong.



I plan my tasks with resources and durations such that I can get my milestones to occur from the forward pass to be where they should be.



No matter what software you use, if you use constraints to force the software to give you the answer you claim to know that it should be, what you are doing is welding bits of rebar fore and aft of your tasks where the rebar represents a time of varying lengths and being all surprised when the end task is out into the future past the required end date.



I am with both Mike and Trevor, MSP is a schizophrenic piece of software. Both Crap and OK



Some people spend the time in understanding how to plan and schedule using Gantt charts and can apply MSP to produce an answer.



And without a doubt (from all of the to and froing of hate, love etc for MSP) most people CANNOT actually use MSP, because they have been conned, brainwashed or what ever into believing MSP is "Simple to use and you can produce a plan in minutes",



Well my friends as I know from over fifty years of Planning & Scheduling , as well as writing Critical Path software for use in planning and scheduling, MSP is probably the most COMPLEX piece of programming ever produced.



There are over 500 different blogs, expert help pages etc on MSP, with well over 200 million pleas for help and asistance trying to get MSP to deliver.



Thus, Bo, if it was easy, there would n’t be anywhere the need for those pages



If you want to run a proper project plan, with Resources, Multiple Calendars and Date constraints that work and want to do Earned Value you should be using Micro Planner X-Pert for Windows.



At least it is predicated on Critical Path practices and Principles as design by Kelly & Walker back in 1956/7



Phew, you got me going again, I swore blind I was going ignore PP, but too many people now have my personal e-mail and keep on asking why I don’t respond ..... now you know



Raf

Hello all,

Bo is right when saying MSP is not "specialist friendly"; I would add, MSP is definitely not "Primavera specialist friendly".

However, when teaching MSP to trainees, I always emphasize on the fact that MSP is not "so user friendly", as it looks close too much to MS Excel; when trainee planners have an experience of scheduling small projects in Excel (a situation not so rare in France), it is more difficult to teach them MSP because they have to understand MSP is not MS Excel.

On the other, whatever is the software you will work with, it is a much better idea to learn to use it before starting using it in the real world.

Alexandre

Hi Mike,



"...I have learnt a lot from it..." - I was almost sure I couldn’t teach an old dog new tricks.



Cheers,



Bo

Hi Bo



Thanks for that dissertation - I have learnt a lot from it.



I used the word "crap" to see what response there was out there.



It seems the replies are currently balanced 50/50.



Best regards



Mike Testro

Alka,



A FNLT constraint should not move a task up to its latest finish date, it just tells when it latest can finish – not must. So if you are telling us that P6 is giving you “when to start your first activity latest when applying a FNLT to the last activity” I would state that P6 does it wrong. What you are looking for is probably the ALAP in combination with the FNLT: Apply FNLT to the last activity and ALAP to the first one in your series of 10 tasks and you get the result you want in MSP. Ok, admitted, the ALAP function doesn’t work correctly in MSP as it consumes total float – also for successors, so you can’t use the above solution in other software packages. Here you probably have to apply ALAP to all 10 tasks. And when having more than just 1 series of tasks in MSP, you have to be very careful (read: never) when using the ALAP in MSP. Another solution in MSP is just to pull up your “latest start” column – and maybe even add a bar style for this on the Gantt chart.



When that is said, this is about the only disadvantage that MSP has concerning constraints IMO – well, it maybe is also missing a feature for zero free float constraint and zero total float constraint (i.e. always critical). With respect to all the cons Alexandre is listing, for me it is simple logic that as soon you start to mess around in the start and finish columns + drawing any tasks on the Gantt chart you are dealing with some kind of constraints, so I never (or as close to) operate in these locations – except maybe for some special start / finish milestones now and then. As I rarely (deliberately) have constraints in my programmes I basically only operate in the “Task Name”, “Duration”, Predecessor” and “Successor” columns. I find it very cumbersome and slow to draw tasks and links directly on the Gantt chart, so when working in e.g. PowerProject or Pertmaster (I simply won’t call it by its new name), the predecessor and successor columns are always visible and presented so links can be written easily here. Use of constraints is a “try-to-avoid” for me.



IMHO, MSP is the most user friendly system of them all. Anybody with no prior knowledge of planning software systems can within a few hours produce a simple programme in MSP, which would take a day or days in other planning systems, so therefore MSP (in construction) is good for many site engineers, agents, foreman, supervisors, engineers based in office, etc. that is only doing programming “now and then”. i.e. not 100% planners. Furthermore, it is cheaper than many of the other systems on the market. MSP is not “specialist friendly” (or “delay / claims”-friendly) because its lack of features and at certain times lack of sound theory, but that doesn’t mean it is not user friendly. Moreover, the auto-filter function and customized fields function are 2 very user friendly features I miss very much when utilizing other systems – but then again, MSP lacks a lot of nice features which e.g. Powerproject and Pertmaster contains.



With respect to the situation Rafael mentioned with “expected finish constraint” I’m almost certain something similar can be simulated in MSP by use of customized fields with an iif-formula, expected finish date minus early start date, maybe a flag and maybe a user made bar style (again with a flag) to show the result required.



Sorry it became a bit too long, but I’m fed of people slagging of MSP so easily, if they haven’t spent enough time investigating its potential. Admitted, it is not the best system, but it is definitely not crap.



Regards,



Bo

This stuff is easy in MSP too, but not if you are basically doing it wrong, and especially if you don’t have a good understanding of the Critical Path Method, what it does, what it is for etc.

CPM is about scheduling forwards from a known(or assumed)start date, and building a network based on the durations and predecessor relationships. CPM only (generally)requires FS0 links. The further you depart from straightforward FS0 links the trickier it gets.

The objective, and it is important to keep this in mind, is not to find the start date, but to find the finish date.

If you already know the finish date you don’t need the software.

Why did you link the 10 x tasks together FS in the first place?

So that MSP can find the (earliest) finish date for you, which it has done.

But you seem to have found the finish date, and found it not to your liking (because you have an earlier one in mind) and jammed a FNLT on it.

You have not told MSP to move the start date back to allow the middle part to fit, so why should it assume that’s what you want? You say, contrary to the evidence and everything ever written about planning, CPM and MSP, that it should move back the start date. Why? It shouldn’t, it can’t, it won’t.

But it does try quite hard to help you, by warnings and prompts, but you ignore or misunderstand the warnings and prompts.

When you jam in the FNLT (say 10 days earlier than what the CPM says it can happen) on the last task, this causes all of the CP predecessors to pick up negative slack (float). You can see the slack in the Schedule Table. If your first task has -10 Days of total slack, MSP is trying to tell you to move the start date back 10 days. Try working with the tool instead of against it.

Rafael,

you just can’t; unless you consider the "Deadline" pseudo-constraint as close enough to Primavera’s "Expected Finish".

Alexandre

I use SureTrak; one of the constraint types I frequently use to automate updating of long lead deliveries within my monthly updates is expected finish constraint where remaining duration is calculated from early start to this constrained date. How you model this in MS Project?



Best regards,

Rafael

Mike,

unfortunately, you cannot switch this behaviour off...

The cons about constraints in MSP (all versions up to 2007):

1. drawing a task from left to right in the Gantt creates a SNET (Start No Earlier Than) constraint

2. entering a date in the Start column does the same

3. entering a date in the Finish (End) column creates a FNET constraint (why not a Finish No Later Than?)

4. you cannot have two constraints on the same task; should you enter dates in the Start and Finish columns, MSP would only consider the last one

The pro (only one, therefore no S required!):

Constraints display in the Indicators column, by default on the left of Task Name in the Gantt Chart view.

Primavera softwares, PowerProject, Sciforma PS, ... are much more user friendly, as they use a specific field to store constraint dates.

Alexandre

Mike, it’s no trouble, really.

The Indicators Column, which should always be visible, shows a little icon, with an explanation when hovered over, when there is a date constraint on a task, without having to go to Task Information.

Also, if dragging the bars causes a date constraint, as we know it does, and if that is not what is wanted, here’s a tip, don’t do it.

Intuitive? what is, really? Do I complain because my guitar is not "intuitive" (ie I can’t play it without study and practice so that I understand it)?

Perhaps Alexandre’s advice should be "be careful to read what’s in front of your face, that’s why it’s there.".

Hi Trevor



Alexandre has just given you one example.



The system is just not user freindly or intuitive.



Regarding constraints - if you draw a new task it puts a constraint on it by default - I have not yet found how to switch this off or change the default.



In most systems you can see if there is a constraint on the task - P3 even has an asterix and Powerproject shows a relevant flag - in MSP you have to go and look at the task info.



Another matter is the date and duration default format - never yet found out how to change it.



Please don’t go to any lengths to show me how - I only keep the software so that I can convert programmes to Pwerproject.



Best regards



Mike Testro

Alka,

do not forget to enter the corresponding date when you select a constraint other that ASAP or ALAP!

MSP will not warn if you don’t, because the constraint will affect the regular Start or Finish date, not a special one as in P3.

Good luck with MSP, it is not so easy jumping here from P3.

Alexandre

Mike,

As you know, I agree with you about most things such as the abominations and the FS links.



How about just one example of MSPs alleged inferority, besides just generally slagging it off?

In my experience the "crap" is what gets produced by the user, and the software makes no difference.

Hi Alka



Right click the task > Go to Task Information > Advanced > Constraint Type and select the type you want.



Good lick with MSP - its a crap piece of software - much worse tha P6.



Best regards



Mike Testro