I am using Epoxy to adhere old earrings to metal hair clips. I have been using a Dremel to roughen up the surface of both pieces prior to using the epoxy, for better adhesion. The problem is that sometimes its hard to judge how large an area to "roughen up" and sometimes I go overboard and the finished piece consequently doesn't look as good. How important is it to roughen up? Can I get away with roughening only one of the pieces instead of both, or not at all?? Also, on a related note: I am using a sharpie marker to indicate where I should be roughening up the metal, problem is that sometimes the black sharpie mark shows on the finished piece and I can't get it off because the epoxy has dried over it. Any suggestions?
My suggestion is to stop scarifying just shy of the Sharpie line then take some acetone and remove the Sharpie line prior to placing the epoxy on the metal that way there is no black line left on the metal, end of problem. And yes, for a better bond I would still rough up the metal ever so slightly, just don't go overboard with it.