Experimenting with etch resists

Today I tried two substances as etch resists for electrolytic etching. Etch resist marker, designed for chemical etching of circuit boards, and black acrylic paint. Neither were great, I must say. The etch resist pen worked, but came off very easily when I brushed the surface to remove copper crud. It could work, but I'm not doing any fine art with it. The second, acrylic paint, was a TOTAL FAILURE. Tip: Never use water-based substances as resists. They dissolve in the bath. Photo one is before etching, photo two is after.








I didn't touch the front surface on the second one before taking the photograph. Once I scraped the paint off, I noticed that the whole surface had been etched the same amount. I reiterate: Never use water based substances. Ever.