Journal
Plotting the first hour after a changeover
Changeover clocks often stop when the last bolt is tight. Production clocks start when the first good pack is labelled. The gap is full of small permissions: quality release, metal-detect test, a missing inner, a printer that still holds the old date. Those minutes rarely earn their own stop code.
Count good units in fifteen-minute blocks for the first two hours of each observed changeover. Put the rest of the shift beside them on the same chart. If hour one is half of hour three on three changeovers in a row, the loss is a pattern, not a bad crew.
Note who has to be present. A start-up that needs a setter who is also covering another hall will wait. That wait is a roster fact, not a training slogan. Factory managers can move a setter’s first hour more cheaply than they can buy a faster machine.
Leave the chart on the line for a week after the visit. Crews correct our labels when they see their own changeover. Those corrections are part of the record, not a nuisance.