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White flow marks caused by new PT line

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Q. We have taken new PT line from Henkel but we getting white patches on parts?

CED white patches and flow marks 1

Anurag Varshney
- UTTAR PRADESH, India
December 7, 2023

A. Hi Anurag.
"PT" means what, "pretreatment"? Sorry but I can't follow what this is about, and that thousand-candlepower flash has scrambled my brain. Do we interpret that pic as showing that 85% of the part's surface has a white haze on it instead of still being steel colored after pretreatment? Can you give us a little more background what you are talking about and what you are trying to illustrate? Thanks!
Luck & Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

Q. Sir this is pretreatment line and lots of white flow marks, dust particles visible at end stage if cathodic electrode position.

CED white patches and flow marks 2b

Anurag varshney [returning]
- Up, India
December 18, 2023

A. Hello again Anurag,
I think the features you are trying to call attention to would be more evident if you turn off the flash on the camera; it seems to hide things by washing out what you want us to look at.

But, yes, the first picture, with drip marks below several holes, seems to indicate a severe rinsing problem which results from not quickly and evenly removing the treatment chemicals from the surface. However, that bright white dashed vertical line above the flash in the second picture looks from here more like mechanical scraping damage than a chemical processing defect.
Luck & Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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