Troubleshooting a Non-Cyanide Alkaline Zinc Bath

Are there rules of thumb for troubleshooting a non-cyanide alkaline zinc bath?


Related Topics:

Q. Do you have a troubleshooting chart for non-alkaline zinc plating baths? –S.S.

A. The chart below covers some of the more common problems that you may encounter with a non-cyanide zinc plating bath. Keep in mind that the vendor of the chemicals used in your bath is your best source for this type of information.

Problem

Possible Causes

Possible Solutions

Blisters

Brightener too high

Carbon treat or zinc dust

 

Inadequate cleaning

Better cleaning cycle

Bath chemistry off

Analyze and correct

Organic impurities

Carbon treat

Chromium contamination

Dummy or sodium hydrosulfite

Metallic contamination

Zinc dust treat

Burned/dull high CD areas

Brightener low

Hull cell and adjust brightener concentration

 

Temperature low

Adjust temperature

Metal content low

Raise metal content

High CD

Lower CD to specified range

Dull low CD areas

Brightener low

Hull cell and adjust brightener concentration

 

Bath temperature too high

Cool plating bath

Sodium hydroxide concentration low

Add to a minimum of 60 g/L

Organic contamination

Carbon treat

Cloudy deposit

Brightener low

Hull cell and adjust brightener concentration

 

Metal content high

Analyze and dilute bath

Iron contamination

Dummy bath

Zinc concentration drops rapidly

Anode area low

Increase anode area

 

Sodium hydroxide concentration low

Analyze and add as needed

Anodes polarized

Increase anode area

Zinc continually increases

Anode area high

Reduce anode area

Rough deposit

Suspended particles in bath

Check filtration system

Excessive brightener consumption

Metal content high

Analyze and reduce

 

Bath temperature high

Reduce bath temperature

Organic contamination

Carbon treat

 

Related Content

Top Shops: Part Inspection Hours Per Week

In the latest Products Finishing Top Shops Benchmarking Survey results for electroplaters, the Top Shops spent 240 hours a week checking part quality and looking for imperfections.