How to reduce scrap, rework and shift to shift variation

The good news is that your company has developed standard work procedures. The bad news is you may not be doing a good job training your people. The fact is, "training" is a skill. Supervisors are often given this responsibility with the assumption they know the work and therefore know how to train. Unfortunately, nothing could be further from the truth. Having worked with hundreds of companies, I can assure you this is a major obstacle in meeting lean manufacturing objectives.

It is time to shift our thinking: If the student didn't learn, the teacher didn't teach. It is not "their" fault but "our" fault. People learn by breaking the job down into manageable bites. They must understand and recite the important steps, key points and reasons why the key points are critical to the job and safety. Finally, they must demonstrate and repeat the targeted task at least 10 times minimum. People learn by repetition and past mistakes.

This process, TWI, was employed by the U.S Government during WWII. Thousands of women had to be trained quickly and efficiently to perform jobs they had never done before to support the war. It worked very well. It worked so well that this methodology was adopted by Toyota after the war and is a big part of the Toyota Production System today. It is not a substitute for SOPs but rather a teaching tool designed to eliminate variation in the training process itself.

As a certified TWI trainer, I will be happy to discuss how this process can help reduce scrap, rework and shift to shift variation.