Intro
14%
Diagnostic workflow when a die starts losing tolerance
The triage order that keeps a shop from replacing a working die because the spray bar moved. Part first, die surface second, process third, press last.
A die at 60K hits, running on spec all morning, starts producing parts 0.05 mm over tolerance on a critical dimension after lunch. The shift supervisor walks the press, looks at the die through the open guard, sees a heat-check pattern that "looks worse than it used to," and signs the die-pull paperwork. The replacement die is on the bolster by second shift. The original die goes to the rack with a tag that says "worn out at 60K." Six weeks later the new die starts producing the same out-of-tolerance parts at hit 8K. Somebody pulls the spray bar cover and finds a clogged nozzle on the same corner of the cavity.
The cost of that mistake is not the new die. It is the assumption that the die was the variable. The triage order is what keeps that assumption from being the default. Cheapest diagnostic first. The die is the most expensive thing in the cell. It comes near the end of the triage, not at the start.