Why it works

Mechanism	A mold makes good parts only within a range of settings, and on some molds that range is narrow. A change one shift makes to cure a flaw can leave the press near the edge, where parts start to go bad. Test runs find the edges, so the press can run in the middle. One sheet gives every shift the same start, and a signed change shows who changed what.
Math	The plant molds about 5 million lb of plastic per year, and each percent of it costs about $75,000. We assume the test runs stop 20,000 lb of scrap per year, 0.4 percent of all plastic molded, worth about $30,000. That is about 21 percent of the scrap from the six molds that scrap most. Adding 20 percent for the press time and labor in those parts makes about $36,000. A technician's time to keep the settings, about 120 hours per year, costs about $6,200, which leaves about $29,800. The test runs take about 72 technician hours and scrap about 1,200 lb of test parts: about $5,800 once. They pay back in about 2 months.
Industry evidence	Published cases report scrap down by 1 to 3 percent of the plastic, where molders set presses by test runs. Those molds also had pressure sensors, and the cases come from companies that sell the sensors and the training. No case we found measures test runs and a settings sheet alone. So the share we assume is our own estimate, set well below those cases.
Limitations	New settings do not fix a worn or damaged mold. If rejected parts have the same flaw in the same place, the mold needs repair in the mold shop. Some customers approve the settings a part is made with, so a change needs their sign-off first. About $6,000 of the figure is press time and labor, which is cash only if orders fill those hours or overtime falls. The sheet works only while every shift uses it.

Illustrative sample. The plant, the walk and the footage are synthetic. Figures from our analysis are estimates made with AI, not guarantees.