Page:Cyclopedia of Painting-Armstrong, George D (1908).djvu/227



Interior Finish—Old Work. In repainting a surface that has been painted, varnished, enameled or stained a number of times, it is important to know the character of the surface to be finished, the kind of work that can be satisfactorily done over it, also necessary to know how to properly prepare the surface to receive the finish, as well as to know that certain kinds of work cannot be successfully done over numerous coats.

Flat white and enamel cannot be applied over numerous coats of oil paint, as they will turn yellow and are liable to crack. Grained work cannot be successfully done over an enameled surface, as the surface is so hard and brittle that when oil graining colors are used, it is liable to break loose, chip, crack or check. A surface which has been enameled cannot be successfully refinished except in enamel. The only satisfactory way to remove enamel is with paint remover or to burn the surface.

Painting cannot be done over numerous coats of varnish without danger of checking or cracking, therefore the varnish should be removed before the paint is applied. Where numerous coats of oil paint have been applied and are of a spongy character or have not dried solid, the surface should be burned or the paint taken off with a paint remover. If the surface is cracked or alligatored, it should be cleaned to the wood with a burning lamp or paint remover. If the work is badly cracked and will not permit of burning, it should be painted in flat color. Cracks will not show so badly finished in flat as in gloss.

Oil Paint. Where oil paint is to be used over old work, sandpaper the old paint to a smooth surface and apply a coat mixed with half turpentine and half oil. If more than