Step 5 of 5
75%
Running forge dies: why this course exists
The same die, built to the same print and treated to the same spec, lasts 30K hits in one shop and 120K hits in another. The spread lives in four operator-controlled levers, and that gap is the subject of this course.
Step 5 of 5Change-out timing as the fourth lever
Every die has a moment past which pushing one more shift gives back more in scrap rate and downtime risk than pulling the die now. The decision lives at the intersection of hit count, scrap rate trend, crack length on the last inspection, and the repair option still on the table. A die that crosses from a 0.5% scrap rate to a 3% scrap rate over two shifts is sending the signal. A die with a crack length that has doubled between inspections is sending the signal. A shift schedule that wants one more run is not a signal. Lesson 11 walks through the decision framework. Lesson 10 covers the repair-versus-scrap branch that feeds it.
Quick check
A die at 78K hits on a 100K-hit ceiling shows a scrap rate climbing from 0.4% to 2.8% over the last two shifts and a crack length that doubled between the last two inspections. The shift supervisor wants one more run before pull. What is the engineering answer?