You will rarely find me writing an article in the first person. I have always felt that the best way to engage my molding peers in the depth of the topics I cover is to put them in the driver’s seat. However, this article is best presented with analogies and 30 years of experience. As such, I will cover 10 scenarios that cause scientific molding–based companies to fail in their utilization of the principles they attempt to practice. Trust me: There are many more I could outline, but to prevent readers from sleeping through my soapbox episode, I will limit my scope to 10.
Too many “medicine men” and not enough processors practice the scientific molding ideology that John Bozzelli created. I personally remember sitting in a classroom in the summer of 1993 as John taught his program. It changed my entire view on molding. Beyond that, it molded the next 30 years of my career. I learned the importance of process development and recording, and it has always steered me away from false readings and refined my analysis of what a true process really is.
It is important to understand the tenets of scientific molding. Outlining all the steps would be an article in itself. At the end of the day, scientific molding encompasses a series of steps that first establish a solid repeatable process, which is then validated. The general rule I use in validation is that if a process is true, a press meets or exceeds production requirements for a period of 24 hours with minimal (1.5%) to no scrap.
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Another key rule of scientific molding is that set up (both changeover and process input) is standardized. This means that the new job is easily changed over without variation, and start up is achieved without a major scrap or process adjustment phase. A true process starts up quickly with, at most, minimal adjustments.
The next step is process control. Process change limits are established to ensure that process consistency is maintained. Process changes that stray outside of those limits are viewed as “red flags,” requiring a deeper assessment of what changes have occurred.
Lastly, any and all historical data are recorded for future analysis. It is important to note that when processes go “bad,” it isn’t the process that fails. Data give direction as to what changes have occurred, and in most cases provide a troubleshooting blueprint, which is used to correct whatever change has developed.
With this, let’s address the meat of the topic—why molders fail:
1. Button-pushing cowboys. Many times over the years, I have seen this situation. Rather than try to identify what has changed, a molder instead just starts pushing buttons in an attempt to correct. They should be asking, “what changed?” Process control is set aside, and process limits are totally ignored. In all situations where a