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1950-51 Theatre Catalog, 9th Edition, Page 415 (393)

1950-51 Theatre Catalog, 9th Edition
1950-51 Theatre Catalog
1950-51 Theatre Catalog, 9th Edition, Page 415
Page 415

1950-51 Theatre Catalog, 9th Edition, Page 415

Zinc Dust Paint-Zinc dust is metallic zinc in finely powdered form. In the production process, a slight film of zinc oxide forms on each particle.

Being electro-negative to iron, zinc dust is, when mixed with special vehicles, highly efficient as a rust inhibitor; and, as a priming coat on metal under other paints, it is eiiicient in preventing cracking and scaling due to rapid change of temperature.

Casein Paints are products known as Nwater paints." The binder in these products is casein (derived from milk) with a non-toxic preservative.

Casein paints are furnished as a dry powder to which water is added by the user or as a paste to which additional water is added. They are all available in tints, as well as white.

While used largely for final coatings on interior walls, casein paints are also used as priming coats, especially on plaster, under oil paints and enamels, and as an opaque coat between the first coat and the third coat of oil paints. In the case of the plastic casein paints, use is primarily that of texture decoration and is, as a result, produced as a plastic product rather than a fiuid one.

Some types of casein paints are especially adapted to the illumination of industrial buildings.

Cement Paint-The name, cement paint, was formerly applied only to paints designed to protect and embellish cement, concrete, or plaster surfaces. More recently, however, it has been used to designate paints containing Portland cement.

Cement paint, in this more modern sense, was devised to replace ordinary paints which do not adhere well to surfaces of this type. Modern cement paints can even be safely applied to new, even wet cement and similar surfaces.

Preparation for Repainting

During the war, the paint-neglected surfaces of our country were losing a battle with the sun, rain, and other natural enemies. Many paint jobs that were due had to be postponed, and deterioriation set in to a greater extent than in normal times.

Before any painting is done, all necessary carpentry, masonry, and other work should be repaired. Loose boards should be securely fastened, badly split or rotted lumber replaced, mortar joints pointed, loose chimney brick cemented, corroded gutters and downspouts replaced, shingles installed where needed, roof coatings used where necessary, windows and doors caulked, new window panes substituted for broken ones: all these preliminary jobs should be done.

Next, surfaces must be properly prepared. All loose paint and all foreign material must be removed. Loose paint and efiiorescence (salt peter) may be removed with a scraper or wire brush. Scrubbing with a cleaning solution may be necessary for the removal of mud and grease. Sometimes small patches of paint will defy the best efforts, yet, for best appearance, they should be removed with solvent paint remover, electric paint remover, or torch.

Wooden surfaces are cleaned (1) by scraping and wire brushing and (2) by burning and scraping.

Scraping and wire brushing is used primarily on very large wooden surfaces.


PROGRESS THROUGH THE YEARS is shown in this and the following five pairs of comparative photographs. all of which have been provided by the Sherwin-Williams Company and M. Van Loo, its director of paint research. In each set of pictures, the left represents the effects on cedar urn-d the right on yellow pine. 'l'op picture shows the 1927 formula alter four years' exposure in Chicago.

THE 1935 FORMULA shows (middle picture) an advance in quality, as represented on the cedar and yellow pine samples, after four years' exposure in Chicago. In three more years, in .1938 (bottnrn picture) still more progress is made. Here the tests were photographed after. tour years. exposure in Chicago. All the pictures in this series were photographed at MS. but reduction here brings it to x2.
1950-51 Theatre Catalog, 9th Edition, Page 415