Root Cause and Corrective Action

Root Cause and Corrective Action for the New Guy

During a recent transition, I received the daunting task of finding Root Cause and Corrective Action in a machine shop. I was unfamiliar with manufacturing machined details. I previously worked with manufacturing assemblies and installations. Detail machining was completely new to me and so were the terms and processes.

In the Beginning

My first goal was to get familiar with the basic concepts and terms. After completely immersing in all things machining, I was ready to completely revolutionize the way our shop operated. In a few short months the shop defects would plummet, the machinists would actively seek process improvements and the corrective actions would be resolved flawlessly.

Ignorance is Bliss

With a small list of defects, I proceeded to get all the information that I could from machinists that were completely open and helpful. Feverishly writing the responses to any of my questions, I got some great information and several action items. After collecting my thoughts and sharing them with the shop manager, he looked in amazed silence for a few seconds and then said, “that’s what they told you, it was completely made up.” Additionally, I failed to get more useful information the first trip and the second trip and a few more trips to visit with the same machinist. A couple weeks proceeded in approximately the same manner with several trips from my office to discuss product defects.

A New Plan

Clearly, this approach did not get the expected results. To get enough reliable information quickly, I needed a new plan. First, I attempted to find all the possible root cause and corrective action. Gathering all the variables in machining proved to be an overwhelming task, but several themes kept recurring. Taking a page from some previous classes, I started working on a relatively short questionnaire. Through a couple of refinements and applying some basic structure to the questionnaire, all the information could be gathered in one trip following a short interview.

Root Cause and Corrective Action

After testing the questionnaire with a few machinists, we were ready to begin using this tool frequently. The survey has been a great tool to make sure each major process is considered. More information a gathered with less interruption to the machinist by remaining on-task. There have been very few follow-up questions because we consistently cover everything on the first attempt. Most importantly, the number of actions from each defect has risen dramatically because we are able to address the Root Cause. 

Young Grasshopper

My illusions of grandeur were quickly dashed by the shop manager, but we have seen an improvement in the quality of our Root Cause and Corrective Actions. As we continue to improve the cultural shifts, I anticipated may become a reality. We created a useful tool to help structure the way we review problems in a systematic way that fits into our culture.