After washing with hot water in order to remove the non-stick coating, there starts the stage of uncovering, through polishing, the different colours of the piece in the relevant areas. The surplus material remaining form the union of the sections should not be broken apart but filed down to avoid cracks in the junctures. We use sandpaper, in this case a 400-grit one. Sometimes it is convenient to wrap the sandpaper around a small, wedge-shaped piece of hard rubber. The bandages on the fingers serve to prevent hurting oneself. In the deep places, we use a burin to eliminate the surplus. The last bits of plaster are removed with a needle.