I use fairy power spray works a treat if you leave it for bout hour or two, and doesnt damage the model in slightest (i left some in for couple o days
lol) , just leave to soak, then scrub with old toothbrush
+ its only like £3 from supermarket
lol bargin!!
link bellow incase you wondering wat to look out for
http://www.fairy-dish.com/products/powerspray.aspx
T-M