Presented by : Bimlesh Arun Shailesh Prajapati Sneha B. Hulkoti

 In simple terms time n action calendars are pre-production (also known as merchandising) activities in apparel manufacturing that are synchronized based on inter-dependencies between succeeding and preceding activities.

 A critical path consists that set of dependent tasks (each dependent on the preceding one), which together take the longest time to complete.  Critical path based time and action calendar concepts have been used in apparel manufacturing for scheduling pre-production activities with a goal to deliver order within the original delivery date.

 The activities of critical path are critical in the sense that even a single minute delay in any of the critical activity will delay the whole process (means missing the delivery date)  whereas delay in non-critical activities may not delay the whole process.  Always distinguish between critical and non- critical activities and set your priorities accordingly.

 It is common practice to set duration of each activities in no. of days.  Firstly often it is not clarified whether those days are working days or calendar days, we must mention it.  Secondly apart from weekend holidays we have numerous other holidays, which we don’t consider while planning.

 Example: Last minute s or faxes like “..due to festival holidays here lab-dip will be sent 3 days late…” to buyer are common phenomenon.  Festival does not happen suddenly, then why we wake up last minute to inform buyer about the delay?  It is wiser to create your own calendar with holidays built-in and then generate realistic due dates in “time n action calendar”.

 Some saw benefits of linking “time n action calendar” to the start of receipt of confirmed order (called forward planning).  while majority prefer linking events to actual delivery dates and plan backward.  Anchoring on starting date or the delivery date all other due date of the activities are automatically generated based on dependency and duration of each activity.

 Odd cases where any in-between activity in the time and calendar takes longer time.  For example say one activity is “importing zipper and received in-house”. Importing of that item requires a particular duration and can’t be shortened. Using normal forward or backward planning may result unrealistic due date for the activity, which can’t be met. Ideally we should anchor this particular activity and generate realistic start and delivery date.

 Generally critical path is defined as the longest chain of tasks based upon only task dependencies. While making “time n action calendar” you must consider both task dependencies and resource dependencies.  A delay in resource availability can delay a schedule just as a delay in dependent tasks.

The following example illustrates the problem better.  Let’s imagine there are 4 tasks A, B, C and D with task dependency shown in picture one.  Time estimates for each tasks are A = 2 man-days, B = 3 man-days, C = 1 man-days and D = 2 man-days. Critical Path based on task dependencies Critical path based on both task and resource dependencies

 One common imagination in Critical Path Concepts is resources are freely (infinitely!) available, that means if 4 different persons are available then the project would take 7 man-days to complete, A-B-D being the critical path.  In practical circumstances resources are not aplenty, let’s imagine task B & C have to be done by same person.  So with resource dependencies (i.e. 3 different persons available) the same project would take 8 man-days to complete. This phenomenon is very common in actual garment pre-production work environment.