Dohhhh! Been so long since I looked at that I forgot there were even different sculpture effects. It is number 9 with size set to 400, then smaller on a second pass. I create a wash over the whole skin and remove bits where I don't want it (engine etc). Then I do 20-30 pixel motion blurs on the wash over each panel of the skin, altering the direction of the blur to match the airflow direction on that section.
