A familiar client called. He wanted me to be at his plant ASAP, to inspect his rinsing system, tell his management that it was fine, and to get them to stop bugging him about it. He insisted that he was doing things the way I’d written about them in recent A²C² columns about rinsing.

My client’s management had another point of view. They had nearly lost a major position in gold plated connectors. Blame for plating quality was ascribed to carryover of chemistry and soil components as dragout from the cleaning to the rinsing to the plating system.

His plant had a five-stage counter-current flow rinse bath system. Performance data purported to show that the water leaving with rinsed parts was indistinguishable from virgin rinse water.

My client didn’t worry about dragout. His system was designed to rinse dragout from parts. His performance data showed that it did that. Is that what you would say about your rinsing system?

Our inspection of his system revealed the unexpected: the design was unexpectedly inadequate. The performance data were unexpectedly misleading. Also unexpectedly, dragout should have been a major worry.