A plastic film spec properly crafted by a packaging machine manufacturer ensures that the film can always be blamed That's what an OEM told me last week.
Over the years, we have tried to partner with packaging machine manufacturers with no success. Now I know why at the tender young age of 63. We have even cited success stories in which our film has enabled frustrated plant managers to have consistent performance at speeds which exceed the OEM's claims.
To use a military analogy, the machine manufacturers are like the tank corps. The tanks take the terriority and the infantry follows. The machinery makers just figure the customer will figure the film out on their own. When a machine is placed, the distributors find it first and swarm in. Another set of problems arises from lack of continuity of supply when the distributor "shops" every order.
The setting of this worn out script which happened last week was the last stage of an installation. The upstream issues were sorted out. The last tech who was packing up and leaving said all three laminated film candidates were bad. Last remaining problem: good end seals, inconsistent back seams and occasional pinholes. " FIrst time it ever happened" didn't do the customer much good.
The panicked customer contacted us. I explained that if they were getting good end seals, they were hitting the optimum combination of heat / pressure / dwell. (The film is the same throughout, therefore the acid test variable is the sealing jaws.) The heat and dwell time were both too high, resulting in "overcooking". Turning the heat down - cooler - solved the problem. Random pinholes in the end seals were the last problem.
Turns out the packages were dropped three feet to the conveyor. The molten film did not have enought time to crystallize. The impact created the pinholes. The pinholes disappeared when the conveyor was simply elevated.
We didn't get a sale out of it and consulted for a lot less than minimum wage.
It's a natural human tendency to blame the party who is farthest away from the scene. In the packaging business, the Napoleonic logic always blames the film first.