Scope of this guide
Intermediate version: symptom-to-cause triage with the confirm-by column — find the variable, run one change, verify.
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 |
|---|---|---|---|
| Burnt, gray nodules on edges/high points | Local CD far above window | Position map vs rack layout | Cut total amps; add thieves |
| Bare spots in recesses while edges burn | Throwing power ceiling | Coverage vs position chart | Aux anode trial on recess |
| Burns after bath cools overnight | Temperature-CD coupling | Temp + amps log overlay | Interlock heat to line start |
| Burns only on new racks | Contact resistance low, current hogging | Contact check by rack age | Balance load across racks |
| Coverage loss with normal burn | Catalyst ratio drift | Hull cell + titration | Correct sulfate ratio 100:1 |
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: chromic acid mist is a carcinogen and burns skin. Exhaust running before load-in, face shield, and immediate first aid for any chrome burn.
FAQ
Burns AND bare recesses together — which first?
Geometry: thieves for the burns, aux anode for the recess. Amps alone cannot fix both ends.
How does temperature mask as a current problem?
A cold bath burns at the same CD that plated fine yesterday. Overlay temp and amps logs to see it.
What does a coverage Hull cell show?
Narrow bright band = ratio or temperature drift; the panel predicts production before parts do.