I've been stripping a couple of old metal 2nd edition Ogryns for my Traitor Guard army and have found a nice product for finishing off the stripping process before the primer coat. I initially use nitromors or acetone for removing the paint, then rinse with cold water.
The secret ingredient for the final stage is Cif kitchen cleaning liquid and a toothbrush. (Originally called Jif in this part of the world, I think it's one reason why the pronunciation of the word "gif" didn't go the way the inventor of the file intended...).
Cif is brilliant for this job when used undiluted. It's got very strong detergents to remove any oils or paint stripper still present and it also contains micro-granules. These are perfect for surface prep on metal and resin models and act as a coarse grade sandpaper, removing gunk and leaving a slightly rough key for paint to adhere to, making for a more hardwearing paintjob. And your models smell lemony fresh afterwards as well!
