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piscator piscator is offline
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Join Date: Jun 2009
Location: New England
Posts: 850
Quote:
Originally Posted by Norm01 View Post
I had so so results with the chromates and home brew. All those issue went away when I used the Caswell electrolyte. I also think you need to stay wet, by that I mean don’t let the parts dry, go from zinc to rinse to Chromate. I also believe your multiple strikes may be part of your Chromate issues. Whenever I touch a part after zinc I cannot seem to get a good Chromate.
Norm, thanks, I really appreciate your input! You may very well be right about 'staying wet' and not touching the part. I wear gloves, so I'm not transferring oil from my fingers, but the wire wheel I use between strikes may be transferring crud to the part. After polishing on the wire wheel, I do rinse or wipe the part down with denatured alcohol, but maybe that's not sufficient.

Let me ask, in 'staying wet' are you transferring the part from the electrolyte bath, to the distilled water rinse, and then to the chromate without polishing the silver zinc buildup that's deposited by the electrolyte?

Doing it this way, I would think that the chromate would come off when you eventually polish the part. But I'll try it.

By the way, I did try sulfuric acid for my initial acid bath, but I didn't get any better result than I did with the hydrochloric. This is something that Eric at PMB also suggested.

Here's some photos of the E-brake tubes I plated yesterday. As you can see, the silver zinc came out quite well. The chromate photo, I'm embarassed to even post. When these parts came out of the chromate bath they had a consistent, albeit weak, overall yellow cast. In the process of drying, without my ever touching the part, it turned into a splotchy mess.

Before chromate:



After chromate dunk and dry:

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"A man must consider what a rich realm he abdicates when he becomes a conformist." ~ Ralph Waldo Emerson ~ (thanks to Pat Keefe)

Last edited by piscator; 05-06-2019 at 05:53 AM..
Old 05-06-2019, 05:45 AM
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