I am relatively new to reloading and have done about 3k rounds of 9mm and 200 rounds of 45 cases. I wet tumble with SS Pins, Dawn dish soap, and a bit of Lemi-Shine. After tumbling for a couple of hours using a Harbor Freight 6# dual tank rock polisher my brass comes out clean and bright. I immediately spread out the cases on a paper towel on a cookie sheet to dry. My problem is after a couple of days the cases have lost their shine. What can I do differently to help the cases keep their shine/brightness?