Solutions to Problems with electrocoat bath

A. Hi Diago. I think your question is quite broad and abstract, while offering no data upon which to base an answer; if anyone disagrees with me and wants to answer, we'll be happy to print their reply, but I think you'll need to give us a lot of detail before you can receive useful answers. Good luck.

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

A. Difficult to answer; too broad of a question. Need more details. I would be checking the conductivity and pH of the bath and the rinses to look for ionic contamination. Check you temperature as well, as too hot and the conductivity will skyrocket. Get a pH and conductivity from you water supply as well.

Also check the solids in all baths to see if you might have too much dirt and/or solids. How much filtration do you have on the system and how often do you change the filter bags? Other than that verify that your ultrafilter in running right and call you paint supplier and ask if there is anything specific to your material you need to know.

A. Pitting in e-coats can be due to many reasons, such as bath contamination, the bath being out of specification, poor or insufficient substrate pretreatments, dissolved gas in the bath etc etc. It is sometimes manifested as "fish eyes" and is a common complaint in many organic coating systems. I think we need more information and perhaps some pictures.