Schedule backwards from subtask end date

[slickity]

I'm trying to do something similar, except that the fixed date I have is in the middle of the project. I want to schedule backwards from that task for predecessor tasks, and forwards from it for descendant tasks or whatever they're called. Here's a detailed description of what I'm trying to do.

I am trying to schedule a project in reverse order from the end date of a middle task.
The tasks in the project, in order, are Estimate, Design, AFE, Construction, Records Updated, and Close.

The only date that is rigid is the end date of Construction, which is the date the customer needs delivery. Other than that, I just want to schedule things in the most efficient timing possible. So, I want to set a fixed end date for Construction, then make the first three schedule backwards from there so I can figure out when each should start. So, if customer requires item by January 10th, and Construction will take 5 days, it should start on the 5th. Then, if AFE takes three days, it should start on the 2nd, and so on. After the Construction end date, the remaining tasks should schedule forward.

Right now when I try to do something like this, I get a scheduling conflict, with two tasks happening simultaneously, and flow arrows looping back in time.

I'm using Project 2000.

Thanks.

 

[PDQBach]

Take the Construction task, make its constraint "Must Finish On" and give it a finish date.

Take all preceeding tasks and make their constraints "As soon as possible."

Set up your predecessor/successor links.

Take the earliest starting task in each "chain" (can't think of a better term) that preceeds the Construction task and make its constraint "as late as possible". You can identify those tasks by looking at the predecessor cells -- they will be blank.

 

[slickity]

Rockin.
This seems to be doing what I need. Thank you very much.

 

[slickity]

Actually, on closer inspection, this does not completely work. For the tasks preceding Construction, there seems to be an upper limit on how long they can be. Above that point, it still tells me there's scheduling date. It's like there's a Project start date that it won't let me start a tasks before, but I don't understand why. If I make, say, Estimate, Design, and Construction really short, it will make the project start date a lot later. But, if I try to make them longer, I can make them total up to about 40 days, then it gives me a schedule conflict.

Is there any way to show you the file I'm working on here?

 

[slickity]

Oh, I just found somemore detail on the problem.

All the sections of this project I mentioned earlier I have set up under one task. So, it was the start date of the superior project which was restricting the start date of the task, and restricting how far back it could go.

For now, I've just moved the the start date of the project back a couple years because I really want to see this one task and it's subtasks like a project so I can organize a bunch of projects together in one file (none of them has much detail, so I don't think this will get out of hand).

Is there a way that you can make the start date of the project itself float, like the beginning of a task, like setting it to Start As Late As Possible?

Thanks again.

 

[PDQBach]

For the project start date issue:

Project | Project Information ... and set the start date to some date well into the past.