I recently purchased some old rogue trader miniatures off ebay. And while they were a little grungy when I got them, after putting them on bases they have become grey and dirty looking. I'm assuming I must have exposed them to something that stained or oxidized them (the super glue maybe). I haven't painted them yet but I want to see if I can bring back their shine before I do, i want to try and put contrast paint directly on the shiny metal to see if it gets the same effect as contrast paint over a metallic base coat.
You can try out 2 (maybe 3) methods: 1. take acetone and a toothbrush and give the guys a good scrub. Notice that the acetone can "melt" plasticbases and will kill your glue so use with caution. 2. use coke (yes the drinking stuff) and a toothbrush and give 'em a scrub. 3. if you got one you can throw them into an ultrasonic bath. You can find thos things for cleaning rings or glasses. It does'nt have to be a fancy one.
You can do this in line. You will have to clean the minis with water after method 1 and 2 anyways.
your contrast paints/etc need a primer to stick well/at all to metal miniatures. If you want a metallic undercoat, you will probably need to prime, base in metallic paint, then do your contrast paint over that.
Oh! Hehe, I haven't gotten around to painting them yet. I was about halfway through my battle brothers when my battle sisters came in and I got side tracked with them. I'm back on my battle brothers now and I will probably post them in the hobby progress thread when they are ready.