When building concrete forms, you must take preventive measures to ensure that the concrete does not adhere to the wood as it cures. Generally, forms are made from lumber coated in a special type of plastic known as melamine that is slick and nonadhesive. But if you cannot find coated lumber in your area, the next best thing is to use form release oil. Form release oil is available commercially, but is a chemical, which is often distasteful to homeowners who would like to maintain a green lifestyle. However, you can use common, safe, household products to make your own.
Choose a natural oil that is non-soluble in water, does not contain wax, and has a low to no sulphur rating. Vegetable oil is a good choice.
Use a paintbrush to apply a generous coat of oil to your finished concrete form. Concentrate on the interior, and cover the entire surface evenly.
Position your concrete form and pour your concrete as desired. Remove the concrete form once the concrete has cured completely. Disassemble the form, if necessary.