Glazing putty is traditionally made by mixing a base of whiting (finely ground chalk) with linseed oil in various proportions. In woodworking, water-based putties are more often used: they have no odour, and are easy to clean up. They work just as well with water-based and latex sealers. There are now synthetic putties of various types. There are epoxy (two-part) putties which dry hard as iron, and holes can be drilled in if needed.