So I have my 20 year old, poorly painted, miniatures. First thing to do with the repaint is to pull that old stuff off for another go.
I used GW acrylic paint back then (neat out of the bottle... yes ... I know better now) and I have found one effective way to strip paint safely from plastic and metal is to use Dettol.
Now Dettol is some serious stuff. It is easily available in most supermarkets but you have to make sure you get this version and not some of the others. Undiluted it is quite caustic and not at all kind to the skin or eyes (not to mention it will stink your house out).
I use an old metal tin to keep my stripping stuff in. I have an old plastic lunchbox that seals nicely. I normally mix up Dettol and water, very roughly, in around a 1:1 ratio.
I have an old pair of gloves I use when handling this stuff and normally try to wear some latex ones as well to spare the fingers. Make sure you can seal it in a couple of containers because the smell really does linger.
I then tuck it away, in an old baking tray, buried somewhere on top of my model cupboards in the garage, for at least 24 hours. I have left it longer in the past when I have forgotton about it and there was nought wrong with the plastic or metal miniatures after that. It will be easier and quicker to strip if you use a neat solution or leave it longer, but I prefer to err on the side of caution and put a bit of elbow grease in.
Now on this batch you can see what they looked like just being plucked out in the first picture. A bit like their face has been melted in the fire. I would say they could have been left longer but I thought I would clean them up and see what is what.
I normally keep all the old toothbrushes being thrown out for this job. Sometimes it is useful to take them outside in the garden and give them a good scrub, under the Dettol if you have gloves. This time though I used the kitchen sink, both in plain water and a bowl of washing up liquid and water. Just hold them under and give them a good seeing to with the toothbrush.
You will find the paint sloughing off into gooey balls. It will clog the toothbrush up as you go so pull off or rinse in Dettol every now and then. By and large it comes off pretty easily, with just the odd persistent bits stuck in very difficult corners.
I gave them a quick go in the water and laid them on a paper towel and you can see the result above. Not perfect, but not bad, and importantly, no damage or loss of detail.
It WILL generally pull any glued pieces apart, but for me this is fine as I need to get access to these for painting again anyway.
I gave them a further scrub in plain water and rinsed them off.
Above is the result after the clean up. You might see what looks like a green residue. This is just the bubbles from the fairy liquid water. They were gone by the time they were dry.
I then placed them out to dry in the garage overnight. More pics to follow.