I have worked with clients that struggle to reduce scrap and defects in their operations. As we walk their processes, I constantly stop and review the defects and scrap generated at the various work stations. When I show them how to put the defects into categories the light bulb comes on. For example, I show them that ten defective items fall into three distinct patterns. Five have a certain failure mode, three another failure mode, and the last two a different failure mode. From there they can then determine the reason for each failure mode and look for potential solutions.
Another client told me their biggest problem was contamination in the assembly of their electrical components. Even though the operators wore gowns, caps, and gloves, and entered through a blow-off chamber, and wiped down their equipment and work stations at the beginning of each break, contamination was still a serious problem. When we entered the assembly department and got off the elevator, I noticed a filthy rug on the floor. As we walked their process I noticed bits of plastic, hair, paper, etc. on the floor and at many of the work stations. I got the impression that they were going through the motions, but weren’t very effective at controlling the sources of contamination. Pointing out these obvious problems caused them to take a different focus and they were able to reduce the contamination problem significantly.
My advice is to break up problems into different categories and work on them separately. Use a pareto chart to understand where the defects are coming from and attack them separately. Look for places in the process that directly impact the failure mode you’re seeing and eliminate it.
Using these simple techniques can have a significant impact on defect and scrap rates. It all starts with not overlooking the obvious.