Both Liquid Stone and Liquid Art will work great for coating tumblers. The choice comes down to personal preference.Liquid Stone - Shorter working time (15-30 minutes), thicker viscosity, cures slightly harder, 75-80F ideal curing temperatureLiquid Art - Longer working time (45+ minutes), medium viscosity, 65-80F ideal curing temperaturePreparation with Stainless Steel is very important. We always recommend sanding the stainless steel surface with 220grit sandpaper to help the epoxy resin adhere to the surface. Be sure to clean the sanded surface with isopropyl alcohol to remove any debris before applying the epoxy resin. LIQUID CAST WILL NOT WORK FOR COATING TUMBLERS, IT IS A CASTING RESIN.