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Water Spots on EN

We are fairly new to EN plating. Our results have been quite good with regard to production and quality of the plated item. No serious problems have been encountered. However, water spotting is a problem. After the final rinse, we always have water spots. We've tried air blowing the parts, but still get some spots. We've tried wiping the part, but that makes the finish more dull. Ours is Hi-P nickel so appearance is not the primary concern. We would like for the parts to look better simply for aesthetics. Is there an oil or seal rinse we should be using? Comments please?

Paul Norman
- Odessa, Texas
1999

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Normally water spots that show indicates that the final rinse is not clean enough. Try using a mix of tap and DI water or RO water as a mist spray over the last tank and then blow dry as soon as possible or at least blow the bulk of the water off. Some people use a some thing to reduce the surface tension and dip the parts. isopropyl alcohol ⇦ this on eBay or Amazon [affil links] works fairly well if your treatment system and discharge can stand it and it is not going to get into the EN tank.

James Watts
- Navarre, Florida
1999

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Thanks! I tried the idea and it worked. Previously, our final rinse was a sprayed RO rinse. Now, after that, I have placed a static rinse of RO and 10% alcohol which I just quickly dunk the rinsed part into. I blow it off as usual. The spotting is minimized.......I can live with this. Thanks again for the help. P.

Paul Norman
- Odessa, Texas
1999

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Try dipping in a low very diluted chromic dip.

Sara Michaeli
Tel-Aviv-Yafo, Israel
1999