If you were smart and put your skis away with sharp edges and a thick coat of wax covering the base and the edges then you may not have much to do, but for the rest of us it is time to get to work. Cleaning Begin by wiping down the ski with a damp rag. Then secure the ski in sturdy vises and begin work on the base. If there is dirt embedded in the wax make sure that you don't try to scrape it off. Scraping may just work some of that grime into the base, especially the more porous sintered bases.
Traditional bases consist of melted polyethylene plastic that is poured into a mold.
A sintered base is created by compressing, under heat, hundreds of thousands of tiny balls of base material. Because the material is not melted, the chemical composition of the base material remains unchanged. This forms a much harder and durable, yet porous base that allows wax to be more easily absorbed. This increased porosity means that sintered bases can be more work to get clean but the payoff is in longer lasting wax jobs. There are commercial ski wax removers available but they are usually expensive and the citrus cleaners work well and they are safe.