Interested in in producing uneven line work that bleeds somewhat (as shown in details on this illustration by Warhol and another by Ben Shahn). Any experience or where to start? Have recently learned how to scratch through wax for inlay line work, but would prefer something looser-looking. I'm thinking slip trailers could maybe produce this. Or perhaps lightly spraying bisque ware with water before drawing? Dipping a crow quill type pen into a stain to use like ink? One clay better than ano