Page 25 - Injection Molding Advanced Troubleshooting Guide

6 1 Troubleshooting Methodology

see an impact they scratch that variable off the list of potential causes. Remember
that if the change is too large and causes other concerns it can be adjusted back
towards the original setting. Make sure a parameter has been thoroughly evaluated
before it is removed as a potential root cause.

1.4.2„ STOP: Think

Think is the step to make sure that a troubleshooter has mentally reviewed the
defect and the potential causes that were systematically determined. Before mak-
ing a change, it is critical to think through what the expected result is as well as
potential side effects. Always begin the think step with the question of “is this a
new problem or has it been ongoing?” If it is a new problem focus on what changed;
with an ongoing problem the focus is more on what needs to be corrected.
Sometimes in the think step of troubleshooting it is necessary to think outside of
the box. Many problems encountered in molding are not easily solved and may
require a creative approach to resolve. Willingness to not be constrained by com-
ments such as “that’s not the way we do it” is key to resolving problems. As Albert
Einstein said, “we cannot solve our problems with the same thinking we used
when we created them.” There are many examples of molds where someone said
that an area cannot be vented or cooled but through some ingenuity a solution was
found. Remember that there are many exceptions to the general “rules of thumb”;
critical thinking is vital.

Also, when thinking through a problem, think bigger than the current defect that
is in front of you. Always ask if this problem may be happening elsewhere but has
not been detected there. In the case of the 4M machine category, any mold that
runs in that particular machine may be having problems but some will be worse
than others. If one drying hopper is feeding multiple machines a splay problem
may start to show up in multiple parts. Think about the root cause and what else it
may impact and examine other parts that could be experiencing similar problems.
When thinking about a problem look for opportunities to push the thought process
as far up front as possible. Effort put into part and mold design will result in im-
proved process windows, reduced scrap, and more efficient launches. It is much
more cost effective to ensure that the initial design is suitable for manufacturing
rather than trying to correct mistakes after the mold has been built and run.