Getting stuck in problem solving is epidemic. We get stuck on wishful thinking, optimism, hope and a host of other ‘positive’ attitudes. Now, don’t get me wrong, I am not suggesting that these traits are necessarily bad, only that they can be when you get stuck in a rut. Let me illustrate with the most common web control; tension.
Operators have control over tension in one or more spans; it is one of the few universal knobs in web handling. Operators and web handlers alike have learned that tension settings can affect an array of defects; sometimes profoundly. If for those two reasons only, adjusting the tension setting should be one of the first moves considered by web handlers. Let me illustrate with the case of one of the most common web defects; wrinkles. We note that all wrinkles are tension sensitive (yes, this IS true). So we try different tension settings and observe that some (tension etc) settings work better than others (yes, may be true). Still, wrinkles continue more than we like. So we go back to the tension knob and tweak it a bit again. STOP: anyone recognize an infinite loop here? This is a point where countless numbers get pointlessly stuck.
It is beguiling to think that the machine builders have put these knobs on your machine for good purpose; such as to (hopefully) help clear wrinkles. It is beguiling to remember the times you twisted the knob and the problem went away. (Not remembering the times twisting the knob did NOT make it go away. Not considering that the response could be statistically nonexistent; mere chance). It is beguiling to think that a simple twist of a knob might fix a problem rather than to face more unthinkable possibilities like doing nothing, living with the problem forever, ‘fixing something but don’t change anything,’ facing ‘we can’t do (consider) that and so on.
So, how do you get out of this infinite loop, get unstuck? We might first recognize that we are stuck on some form of wishful thinking; known formally as the Pollyanna Principle. However, this could be difficult because we are too close to the problem, have emotional and physical investment in the effort and besides the measure is quite subjective. Rather, we simply note that we have been playing with the knob(s) for a few months now, perhaps (hopefully) with some rigor such as DOE. We then note initial gains have been nice, but seem to have plateaued at a point still not good enough. We now have to do more than consider something else (unless it is to give up; the layman’s pessimistic view of an option that is required by the Dunker Diagram problem solving technique). Now is the time to see what science has to say. (If that fails to satisfy you might then go to exaggerated trials).
In summary, recognize getting stuck by any number of indications listed in my Critical Thinking in Converting short course. Then go to school on science/experience based treatments of wrinkling, such as reducing the root cause or spreading, that is detailed in my Web Handling and Converting short course.