No Advantage to Long Runs

When I ask clients, especially shop floor supervisors and operators, whether they like setup, the answer is universally “NO!” Why? Long setups reduce efficiency and put them behind schedule. They want faster setups and longer runs. They usually cringe when I tell them that the real purpose of quick setup is more setups. It goes completely against how we have been conditioned to think about economies of scale.

The rationale goes like this: By reducing setup time, more setups can be performed without impacting output. Batch size is therefore reduced, without impact on unit cost (since there are many hidden costs associated with large lots and long setups that can now be avoided). This results in a shortening of the production cycle – the time it takes to cycle through all the products assigned to a machine or work center. The outcome is less Work-in-Process (WIP), shorter lead times, more opportunities to improve quality, more flexibility, and better customer service – something not available from longer runs.

So, it turns out that the traditional route to higher efficiency has a downside. It is one of the great ‘aha’ moments when a client realizes this.

Standard Setup Reduction Process

We want high capacity utilization, but not at the cost of large WIP inventories. Quick setup is how we get it. And the fact that setup reduction is not black magic makes this achievable for all businesses.

Let’s look at the steps in setup reduction. I have used the example of a stamping press setup, since this is where some of the fundamental insights for setup reduction were made.

1. Separate internal from external – This means executing the changeover so that all those elements that can be done while the machine is still running (external) will not be mixed in with those that require the machine to be stopped (internal).
   Example: Getting tools, supplies, and material for the next job, before the current run is finished, instead of running around during the setup looking for them.
   
2. Use parallel work – This means doing several tasks simultaneously, by using more people or equipment to do the work.
   Example: One person loads the new tooling, while another is programming the machine for the new job.
   
3. Convert internal to external – This means redesigning tooling and machinery, to eliminate internal assembly steps and adjustments.
   Example: Mounting tooling on common plates, with built-in location stops, instead of using a tape measure to position and check if the tooling is located properly.
   
4. Streamline all aspects of the setup – This means eliminating wasted motion in all aspects of the new setup process, both internal and external.
   Example: Replacing a variety of bolts and nuts with a standard one-touch (one turn, or hydraulic) clamp.

Typical reductions from these steps reduce press setup from hours, even days, to just a few minutes. Efficiency stays the same, or improves, as the production cycle is shortened.