Case Study: Truck Rod Bushing
The Problem Looked Bigger Than the Tool Count
A customer built a 16-cavity tool for a truck rod bushing, but production told a different story. On a good day, only 10 to 12 cavities would run. That’s a significant loss when the tool’s economics depend on full output.
The tool was already in production, which changed the assignment. This wasn’t about designing a perfect tool—it was about stabilizing what existed and recovering as much capacity as possible.
The Root Cause Was in the Split
The issue came down to trapped gas at the parting line. In urethane molding, that’s a serious constraint. The material releases gas during processing, and without a clear path to escape, fill consistency breaks down from cavity to cavity.
In this case, the parting line location made venting more difficult than it needed to be. Once that decision is locked in, the molding window tightens and performance starts to fall off. With urethane, venting isn’t optional—it’s fundamental.
Working Within Production Constraints
Because the tool was already running, options were limited. The focus shifted to practical improvement rather than ideal redesign. We adjusted what we could and pushed the tool toward stability.
The result: 15 cavities running consistently.
Not a perfect outcome—but a meaningful recovery in both output and reliability without shutting down for a rebuild.
The Takeaway
Cavity count doesn’t define productivity—performance does. A 16-cavity tool that runs 10 to 12 cavities isn’t truly a 16-cavity tool.
With urethane, gas management has to be addressed from the start. Parting line location and venting strategy directly determine whether the tool will run consistently or fight itself.
Fixing these issues in production is possible. Fixing them before steel is cut is far more efficient.
