Document jgY3vOrkv4K9NmE0jz8GedQxR

BUILDING. <M Th e Pa in t in g o f Ne w Ex t e r io r Wo o d Drying out Moisture . . . Treating Knots . . . Varying Priming Coat for Different JVoods. . . Purpose of Each Coat. . . Time between Coats . . . Puttying Defects . . . Formulas. Second of a series of articles, designed to be filedfor reference, on the painting of various building materials THE first consideration in the a firm anchorage to the wood for sub painting of new exterior wood is sequent coats. Unless this is accom to make sure that it is thoroly driedplished the paint film will in a short out and seasoned. Otherwise there time become loosened and crack and of white-lead and whiting. Putty made of petroleum and ground cliffstone sand often mars what would otherwise be a good painting job by making yellow nail holes and cracks. will be moisture present under the paint film and that is bound to result in peeling. Exposing the bare wood to the sun for a week or two will dry it out thoroly. Even when lumber is properly sea scale off. The priming coat should not be composed of materials which either produce a very soft film or a very hard, brittle one. In this coat a con siderable amount of oil is required to When the putty has had sufficient time to dry out thoroly, the puttied places should be sandpapered and smoothed down to remove any putty that has re mained on the surface. The following is a good body coat for mula for all woods: soned, no painting should be at tempted if there is evidence of sur face-moisture as will be the case after a damp, foggy or frosty night or a rainy spell. Moreover, it is unwise to do any outside painting in extremely cold weather. If satisfactory results are to be obtained, the temperature should not be lower than 506 Fahr. v Preparing the Surface When sure that the wood is perfectly dry, the surface should be prepared for the first or priming coat by being scraped and brushed to remove any dirt, mud or other foreign matter that may have adhered to it. This done, all knots and sappy streaks should be shellacked with pure al cohol shellac brushed out very thin, care being exercised to work it well into the knots and to cover }4" on satisfy the wood, with some turpen tine to aid penetration. While a single body or second coat formula and a single finishingor third coat formula are satisfactory for ail kinds of lumber, under all climatic conditions, it has been found that some variations in the priming coat are desirable because of the uneven structure and difference in absorptive power of various woods. The follow ing formulas are suggested for the different kinds of wood: for Average Medium Soft Woods, with fairly uniform grain structure, such as white pine, cedar, redwood, poplar, and other woods of this type, the following priming coat should he used: 100 pounds Dutch Boy white-lead 4 gallons pure raw linseed oil 2 gallons pure turpentine I pint pure drier 100 pounds Dutch Boy white-lead I}4 gallons pure raw linseed oil l}4 gallons pure turpentine l pint pure drier This formula makes 6 gallons of print which will cover about 3,600 square feet, one coat. Finishing Coat The amount of oil in the finishing coat should be such as to produce a film which provides maximum protection and good appearance. A very small amount of tur pentine is used in this coat to aid brushing and binding with the body coat. In applying the finishing coat, special care should be taken to see that the entire surface is covered and no spots are left untouched. After the paint has started to set up, any spots which have not been covered, but which are touched up later, will dry flat spoiling the appearance of the job. The following is a finishing coat for mula suitable for all woods: all sides of them. It is advisable to This formula makes 9 gallons of paint 100 pounds Dutch Boy white-lead allow the shellac to dry a half day which will cover about 5,175 square feet, to 4 gallons pure raw linseed oil before priming begins. one coat. For Harder Woods, and woods which 1 pint pure turpentine 1 pint pure drier Number of Coats have an uneven, grain structure and an This formula makes from Cf to 7 gallons excessive amount of sap, such as hard of paint which will cover from 3,900 to Three coats of paint should always pine, fir, cypress, ash and similar woods, 4,200 square feet, one coat. be applied to exterior wood which the oil should be slightly decreased from has never before been painted--a the formula above, and the turpentine in Painting Other Materials thin priming coat and two heavier creased, depending upon the particular characteristics of the wood to be painted. Complete formulas and directions for coats. Two coats only are sometimes printing any of the other materials used used on new wood for the sake of Body Coat in building, such as metal, brick, stone, economy, but it is not true economy. stucco, concrete, plaster, will be furnished A third coat makes a job last twice The body coat should be so designed as to give a relatively hard film with consid- upon request. Simply direct yourinquiry to our Department of Technical Paint s long. m Exterior work should be allowed to dry from two to four days before f| the next coat is applied. In fact, the longer the time between coats the erable hidtng power, but with sufficient elasticity to enable the paint to follow any movement of the surface to which it is applied. Considerably less oil therefore is used in this coat. A fairly large amount ofturpentine is required to give thedesired Service, care of our nearest branch. NATIONAL LEAD COMPANY 0NewYork, in Broadway; Boston, ijt State Street; Buffalo, ti6 ak Street; Chicago, T.'il better. brushing' consistency. 90a West :8th Street; Cincinnati, 659 Freeman Avenue; Cleveland, Before the body coat is applied, the 820 West Superior Avenue; St. y-Slv $ Priming Coat Too much stress cannot be laid upon the importance of the priming coat. The purpose of this coat is to secure primed wood should be gone over care fully and all holes, cracks, crevices be tween joints and defects in the wood should be puttied up. The putty should be composed oflinseed oil and equal parts Louis, 722 Chestnut Street; San Francisco, 485 California Street; Pittsburgh, National Lead <t Oil Co. of Penna., 316 Fourth Avenue; Philadelphia, John T. Lewis ic Bros. Co., 437 Chestnut Street. 1 jj Reprinted from Th e Jt 0000-NLI-000017525