Scope of this guide
Management version: this defect as cost and risk — the metrics, audit points and claim defence.
Series: finishing.com recurring questions answered with platingclub line practice. Parameters are industry-standard starting ranges — confirm against your supplier TDS.
Triage: symptom → confirm → first move
| Symptom | Likely root | Confirm by | First move |
|---|---|---|---|
| Shiny oval spot on one face | Contact mark from dangler/door | Face map vs barrel contact points | Rotate parts; pad door contact |
| Bare kidney-shaped patch | Parts nested face-to-face | Nested pair in load sample | Media ratio up; load size down |
| Line across several parts | Barrel door edge rubbing | Track along door line | Door liner check |
| Ring at part edge | Media imprint | Media type check | Change media size/hardness |
| Mark repeats every load, same parts | Part geometry self-shadows | By-part-family pattern | Family-specific load card |
Cost, metrics and defence
| Cost line | Driver | Metric | Lever |
|---|---|---|---|
| Rework polish | Marks found at pack | FPY by defect family | Media ratio + contact hygiene |
| Media spend | Wrong media for family | Media type vs mark rate | Family cards |
| Barrel downtime | Door wear ignored | Liner inspection completion | Weekly walk with wrench |
| Claims | Marked parts shipped | Audit failure rate | Ship gate sampling by face |
Engineer notes
- One variable per corrective action; verify with the confirm-by column.
- Records beat memory: log every trial on the tank card.
- Two failed actions in a row is a senior call — escalate with your log.
Safety: barrels pinch and loads are hot. Guards closed, hoist rated, heat gloves; lock-out before reaching anywhere near the door.
FAQ
Are barrel marks a quality cost or a design cost?
Both: track by family; design-driven marks go back to the drawing, not the line.
What audit catches door wear early?
Weekly liner inspection with photos; one barrel per week rotating.
Which KPI shows media problems?
Mark rate by family vs media age; replace on the curve, not on failure.