Automotive Connector Housing: Eliminating Burn Marks with Gas Release Core Pins
Challenge
A Tier-1 automotive supplier was experiencing persistent burn marks on 16-pin connector housings. The mold ran a 32-cavity tool with straight core pins forming deep, blind pin receptacles at a depth-to-diameter ratio of 5:1. Despite multiple parting line vent modifications, burn marks persisted on 12-18% of cavities per cycle.
Solution
All 512 straight core pins (32 cavities × 16 pins) were replaced with Gas Release Straight Core Pins featuring SVC (Semi-circular Vent Channel) geometry. The SVC channels provided sufficient venting capacity for the deep blind cavities without requiring any modification to the mold plates.
Results
| Metric | Before | After | Improvement |
|---|---|---|---|
| Burn Mark Defect Rate | 18% | 0.3% | 98% reduction |
| Scrap Rate (overall) | 6.2% | 0.8% | 87% reduction |
| Cycle Time Impact | — | No change | Zero cycle time penalty |
| Pin Replacement Cost | — | +15% vs standard | Offset by scrap reduction in <2 weeks |
"We had been fighting those burn marks for three production runs. The gas release pins solved it immediately — same mold, same process parameters, zero burn marks from the first shot."
— Tooling Manager, Tier-1 Automotive Connector Supplier