Since your experimenting ,try using a bowl and the microwave with your stain..I don`t know if it will work,but ,maybe you can find a setting,on the microwave that will get close to the plastics melting point, without actually melting it..I know that when I use the Mic to make tomatoe soup from the can,it seems to get hot enought to "stain" the plastic bowl..Or maybe try using an electric "crock pot" to keep the "right temperature" let us know how it`s going ..GOOD LUCK..DAVE B.