Can I schedule operations out of sequence or in parallel with each other?

Hi,

Currently, all of our operations are scheduled ‘Finish-to-Start’, like below:

Is there a way I could schedule operation 50 to start after operation 10 is complete? (I.e. leaving the rest of the operation order intact).

The effect that I’m trying to achieve is that operations 20>30>40 can be done simultaneously with operation 50>60>70. The last operation (Op 80), would be started after all other operations are complete.

Thanks kindly for any help!

If that is what you are trying to accomplish, you should be using subassemblies. You can tell the system that subassemblies can run parallel, but not operations past the next one.

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On the Job you can use “Send Ahead” to juggle the Start of operations and Offset Value.

You can use “Finish to Start”, “Start to Start” and “Finish to Finish” in Scheduling.
Here is from the help:

  1. Use Send Ahead Type to define the offset calculation method used in order to more accurately schedule a second operation in a Start to Start operational relationship. Start to Start is an operation relationship that assumes you want to begin two operations at the same time. In reality, however, you will likely start the first, or predecessor, operation before the second, or subsequent, operation. The second operation is scheduled to start after the offset period defined on the first operation.Available Send Ahead Types:
  • Hours - Indicates the offset period is calculated using a set number of hours.
  • Pieces - Indicates the offset period is calculated using a set part quantity completed on the previous operation.
  • Percentage - Indicates the second operation will begin after a set percentage of the first operation’s duration has passed.The value you define on the operation record is the default Send Ahead Type. Whenever this operation is included on a method of manufacturing, this type value displays by default. If you wish, you can override the default Send Ahead Type on a specific method.
  1. For Send Ahead Offset, enter additional time required before a second operation can begin work in a Start to Start operation relationship. Start to Start is an operation relationship that assumes you want to begin two operations at the same time. In reality, however, you will likely start the first, or predecessor, operation before the second, or subsequent, operation. The second operation is scheduled to start after the offset period defined on the first operation.Enter the time you need in this field. This offset time can be calculated by hours, pieces, or a percentage of the total operation length. This value can also be entered manually by the user on the primary operation.The value you define on the operation record is the default Send Ahead Offset value. Whenever this operation is included on a method of manufacturing, this value displays by default. If you wish, you can override this default value on a specific method.

On the Job Operation under Scheduling Factors, set the Type there then re-schedule it to see your changes.

Scheduling in Action

Article last updated: October 22, 2023 02:05

This section gives you some examples which show how the scheduling engine arrives at its results. If you compare these examples against your own scheduling results, you will better understand the logic behind these calculations.

The scheduling in action case studies include:

Case Study 1 - Finish to Start

The following scheduling board displays operations with a Finish to Start relationship.

Case Study 2 - Start to Start

The following scheduling board displays operations with a Start to Start relationship.

Case Study 3 - Finish to Finish

The following scheduling board displays operations with a Finish to Finish relationship.

Thanks a lot for the reply @visionaire

I tried playing around with the ‘Send Ahead Offset’ option. I set all operations to ‘Start-to-Start’ and then entered a send-ahead offset value to define the order I wanted operations to start.
However, in my testing, it still bases this value off of the previous operation in sequence.

E.g. Operation 50 is being offset based on operation 40, rather than Operation 10, like I was hoping.

Is there something I’m missing here or is this how it works?

Thanks for the suggestion on sub-assemblies @jkane.

The challenge I have is that we auto-import our BOMs from our CAD models, so the ‘structure’ is predefined. Introducing sub-assemblies would require either changing our CAD BOMs or checking out every assembly after import and re-engineering the method for each one.

Edit: I might have been thinking about ‘sub-assemblies’ too literally, as components on the BOM.

Presumably, I could do something like this, with ‘ROUTING1’ and ‘ROUTING2’ as sub-assemblies, containing the respective operations.
image
Would I then also need to move the materials under the sub-assemblies, or could the materials still be issued to the top-level?

Thanks very much.

You would need to move the materials to the sub-assemblies that need them.

You can still use the CAD BOM to import, you just need to import them in a different manner. First, you would import Routing1 with it’s BOM. Then you would import ROuting2 with it’s BOM. Finally, you would import the 0 level BOM that is just the part number for ROuting1 and Routing2.

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Yes, it is based on previous operation from what I have seen. @jkane is right, I think SubAssemblies would be your best bet. You can also do mass updates via DMT if you really had to restructure things. We have kind of the opposite issue here, in that all of our parts are single assemblies 0, no subs. This means no indented Bills but is how the whole organizations is structured so every part is built to stock then issued to later jobs as materials.
I think you are on the right track though with the Subs in parallel.

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Thanks for confirming - thought that might be the case.