Document LpK9YYRD7q5xNOBpXXD8jjp6Q

i--^B fyi'tfo.- \ t '.; ' V. % Th e Pa in t in g o f Pl a s t e r ^ Counteracting Free Alkali . . . Sealing Fire-Cracks. . . | Filling harge Cracks with Plaster of Paris . . . Formulas for different Finishes. First of a series of articles, designed to be filed for reference, on the fainting of various building materials FRESH plaster contains a cer has thoroughly dried, it should be tain amount of free alkali, sand-papered down to a smooth, which has a tendency to keepeven surface. paint from drying properly and to cause colors to bleach out. For Number of Coats this reason, it is best to allow In order to insure the proper kind plaster at least six months to dry of a finish on unpainted plaster, out thoroughly or "set" before three coats of paint should be any paint is applied to it. If it is used--a priming coat, a second or body coat, and a third or finishing coat. If the plaster has been painted before, two coats will be sufficient and the priming coat may be omitted. The old paint, if in good condition, serves as a priming coat. inconvenient to wait until the plaster has dried out, the action of the free alkali may be counter Below are theformulas generally followed acted and the pores of the plaster sealed by the use of a size or by in painting interior plaster walls: some chemical method, such as treating the surface with a 20 per cent solution of zinc sulphate m water. Fire-cracks When plaster shrinks in drying, fine, hairlike cracks, known as fire-cracks, frequently appear. Sometimes these cracks are in visible in bare plaster, but be come noticeable after the first coat of paint has been applied. This is because the cracks absorb oil from the paint, leaving a "flat" or glossless line on the sur face. A proper size over the priming coat will usually seal these cracks. If fire-cracks are evident before any paint is ap plied, they may be sealed by rub bing the size on the bare plaster with a cloth or sponge. Preparing the surface Before paint is applied to plaster, all grit and any loose plaster or paint should be removed by sand papering or with a wide putty knife, care being taken not to scratch the surface. If the sur face is not properly cleaned and perfectly smooth, an uneven fin ish will result. All cracks or holes in the plas ter should be carefully filled with plaster of paris, before any paint PRIMING COAT joo lbs. Dutch Boy white-lead 7 gals, pure boiled linseed oil i gal. pure turpentine If boiled linseed oil is unobtainable, 7 gallons raw linseed oi{ with 3 pints drier may be substituted and will in most cases give satisfactory results. Boiled oilis much superior, however, and will often obviate trouble when conditions are difficult. It seals pores in the plaster and prevents suction. The foregoing formula makes 11 gallons of paint which should cover about 5,500 square feet, one coat. SECOND COAT too lbs. Dutch Boy white-lead A gal. pure linseed oil 2 gals, pure turpentine 1 pt. pure drier The formula with the Batting oQ makes 5 to <* gallons of paiat which should cover about 3500 to 4200 square feet, one coat. The alternate formula makes sA gallons of paint which should cover about 3300 square feet, one coat. THIRD COAT (Flat Finish) too lbs. Dutch Boy white-lead t gals, pure turpentine i pt. pale varnish (suitable forename!) A pt. pare drier The Batting oil formula makes 5 to 6 gallons of {iaint which should coverabout 3500 to 4200square eet, one coat. The alternate formula makes 5 gallons of paint which should cover about 3000 square feet, one coat. THIRD COAT (Egg-Shell Gloss Finish) (oolbs. Dutch Boy white-lead IA to 4 gals. Dutch Boy flatting oil H gal. pale varnish (suitable for enamel) too lbs. Dutch Boy white-lead xA to a gats, pure turpentine yi gal. pale varnish (suitable for enamel) A pt. pure drier These formulas make 5 to 5 A gallons of paint which should cover about 3000 to 3300 square feet, one coat. of paint, which should cover about 3750 square feet, one coat. The alternate formula makes 6 to 6}4 gallons of paint which should cover about 3600 to 3900 square feet, one coat. THIRD COAT (Enamel Finish) The white-lead should be first raked with turpen tine to the proportion of three poands to one gill and allowed to stand overnight. The th'inners should then be drawn off ana the pale varnish added to the white-lead. The foiegoing formula should be used for light' colors. It makes 1 gallon of paint which should cover about 500 square feet, one coat. Distinctive 1nterior Finishes There are a number ofout-of-the-ordinary finishes which lend a decidedly interest ing effect to plaster; such as the Crumpled Roll Finish in two or three tones, the Sponge-Mottle Finish, the Wiped-Stencil Finish, the Tiffany Finish, the Satin' Fin ish,plainstenciling, striping and paneling. If you are interested in any of these fin ishes, we shall be glad to send you samples of them together with full directions and formulas. Moreover, our Department of Decoration is at the service of any archi tect who has a special decorative problem to solve. White-Lead Specifications Complete specifications for painting the different materials'used in building con struction are contained in our "Standard Specifications for the Use of White-I,ead Paint" and "Standard Specifications for theUseofRed-Lead Paint." Copiesmay he had upon application to our nearest branch. NATIONAL LEAD COMPANY ing is done. If the cracks are large, theyshould be opened down to the lath, their edges soaked with water, and the openings filled THIRD COAT (Oil-Gloss Finish) lbs. Dutch Boy white-lead New York, m Broadway; Boston, 131 State Street: Buffalo, 116 Oak Street; Chicago, 900 West xBth Street; Cincinnati, 659 Freeman Avenue; Cleveland, 820 West Superior Avenue; St. with plaster of paris. Care should wall. When the plaster of paris Louis, 722 Chestnut Street; San Francisco, 485 California Street; Pittsburgh, National Lead & Oil Co. of Penua., 316 Fourth Avenue; Philadelphia,John T. Lewis Sc Bros, Co., 437 Chestnut Street. A. I. A. File Number 25 c 21