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“U”, “V” or “—” shift start?

Production starts are important since it defines your “Run-at-Rate” and your predictability of meeting customer demand. So is it important ??

Several years ago when Jay Meyers was acting as the chief economist for Canada he surveyed around 30,000 businesses and came to the conclusion that in the majority of cases it took a business 7 hours and 54 minutes out of an 8-hour shift to cover their costs related to labour, material and overhead … leaving only 6 minutes to generate profit and positive cash-flow for future CAPEX … scary !!!

Many operational professionals focus on “FIRST HOUR” and “LAST HOUR” of their internal processes which ultimately can be defined in a shape of a “U”, “V”, or -- … realize that the bottom of the letter denotes that zero production is happening …

Case Study of a “U” Shape

“U” is the natural and most common shape of any shift. As people, we have been programmed to leave a clean workstation at the conclusion of our shift but people are very focused on being able to leave at the end of their shift … remember they view their contribution as being a job. So typically we see a general slow-down of activities during the last hour as people complete the required paperwork and generally start to clean up their equipment and work area … likely with production coming to a complete stop during the last 10-15 minutes to do that deep clean and gather their personal belongings and put on their coats and wait for the clock’s second-hand ding the moment to signal to leave …

With a “U” shape indeed people cheat and rationalize … we visited a retail operation recently where it was acceptable for the employees to tear down display commencing 30 minutes before the store was scheduled to close and the following day they were allowed to merchandize product for the first 60-120 minutes into the start of the store opening.

Visit any retail or hospitality facility during that “Last Hour” and you will see employees cleaning and organizing as they head for the end of their shift and heaven forbid should you want a product or service from an area that they have cleaned.

Corrective Action

Run-at-Rate is typically defined as the last good part of run-at-rate to new part running-at-rate. So you will need to define what is your rate.

Time your shut-down activities and if you have allocated a designated time segregate the activities into “musts” that need to be done daily along with some “wants” divided

over a period of days.

Ultimately observe your last hour and first hour.

Scenario 2 … case study the “V” Shape

The objective of most organizations is how to achieve a very narrow “V” through a shift exchange or during a set-up. There is a plethora of training tips and tricks available to assist organizations on how to narrow the “V” but you will still experience a period of time of no production. The best I was able to ever accomplish utilizing a lot of money for jigs, fixtures and training was to only lose 1 stroke on a stamping press during a change-over, but it was still a “V” although very narrow !!!

Corrective Action

Follow the protocols of SMED (Single Minute Exchange of Dies) to any changeover process whether it is a machine or a shift change. Time all of the activities involved and determine what needs to be internal to the process and what can be externalized without impacting the customer (internal or external) … remember my retail observation as they were ending or starting the shift they were consumed in their 30-inch view and in spite of the company’s cultural desire to focus on a guest they were focused on their tasks and ignoring guests.

You will need to have the ultimate state of 5S where everything has a place and everything is in its place accessible within 30 seconds.

Ultimately observe your last hour and first hour, but even better start 15 minutes before your first hour and linger 15 minutes after the last hour and be prepared to dispatch help to keep your “V” Narrow. I said “dispatch” … not “go do” … since if you “do go”, you cannot observe.

Ultimate case study a “—”

Seamless transitions without any production impact should be everyone’s goal but realistically in many cases it cannot be achieved due to in some cases Physical challenges, or they can be simply a cultural paradigm. At Toyota we needed a gap between shifts for 2 reasons … 1) in case we needed to run the line a bit longer in order to meet our shift target but more important was our constraint with employee parking.

We have seen a lot of paradigm “U” since tradespeople are reluctant to continue an assignment started by another but similar trade due to either pride or concern about potential liability. If you want to test this … have 4 mechanics work at the same time on the same vehicle to complete a brake job …

Corrective Action

Again, you need the ultimate of 5S and some solid Standard Work Instructions reinforced with a robust and rugged TPM to ensure work areas are constantly being sustained.

As employees step away they are leaving their work areas “WET” ready for the next employee to step in without any production gaps.

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