I use a method that I learned from Frick, I think. Get a turkey baster, and one of those rubber pencil holders. Heat some water to ALMOST boiling. Place the pencil holder on the end of the baster, and the carto in the other end. Draw water in, and shoot out into the sink. Do this until it comes out clear and doesn't smell like the
juice that was in it. Next, blow air through the carto until you don't see water or mist coming out. Then, use either a Taryn spin or thermometer shake to get the rest of the water out. place cartos battery end down on a cookie sheet and bake in the oven at 170 for 2 hours. This will get the water that is wicked into the filler out. Take out of the oven and let cool. At this point, they are ready to fill with the liquid of your choice. If you have cartos that the atomizer is too gunked for this method to work, some people soak them in PGA or vodka to clean them. I have not tried that yet.