Popular Science, maaliskuu 1938
Hints on painting walls, machines and fixtures to assure maximum safety, comfort, efficieny
By Ralph G. Waring
In this day of marked changes in business methods, plant design, and operation, it behooves every superintendent, whether he has charge of a large or a small shop, to realize the importance of good painting and lighting. Where needed changes are undertaken under competent supervision, the work can be done at no great cost, and it will later pay for itself many times over in improved efficiency and operating comfort.
Outstanding in this respect is the modern windowless plant. it offers to the architect, the management, and the workers the ideal medium through which adequate light values, essential fresh air, as well as proper machine orientation and operation, are definitely assured.
Contrasted with glass window lighting, artificial light values obtained with the new type of light bulb and modified mercury units throwing 95 percent of illumination agains a properly finished ceiling are so near ideal daylight that only a technically trained engineer with adequate instruments can detect any difference. These units consist of standard glass lamps grouped togerher with bulbs of improved mercury lamps, inclosed in a specially designed reflector.
LIGHT REFLECTION VALUE OF COLOR iN PAINT
Color | Redlection (Percent)
Light pink 69.4
Light green 54.1
Light gray 53.6
Light blue 45.5
Sage green 41
Whatever type of illumination is used, twenty foot candles at the working-table area are desirable, although for fine detail work the factors must be increased.
Superintendents are now aware that they can no longer escape the effects that neglect of good painting and lighting have on their shop morale and production schedules. The day is rapidly drawing near that will mark the end of dirty millrooms and machine shops.
In cases where whitewash of good quality has been used in the past, only a scratch brush is required to remove an occasional blister or peeling area.
By silughtly thinning the first coat of any good white eggshell enamel of the type intended for mill use with a mixture of four parts of commercial turpentine and one part of pure turps, the increased penetration will be sufficient to penetrate the whitewash and secure good anchorage. Use little or no thinner on the second coat.
Where the calcimine work was poorly done or adhesion is bad, the whitewash must be washed off, before painting, with a trisodium-phosphate washing compound. Allow adequate drying time. it pays in the long run to wash off accumulated dust and grime.
In the case of the very modern print shop of the Hershey Chocolate Co., of Hershey, Pa., whose windowless plant is illustrated, all machines were cleaned with trisodium-phosphate washing solutions, dried, wiped with clean rags and alcohol to destroy the last traces of oil, and then painted with a rich, Delft.blue, oilproof machine enamel of a tough, quick-drying type.
The floor is of oiled maple; pillar bases are light gray; the upper portion is a bright yellow; side walls are glazed hollow tile of a mottled-tan color, and the ceiling is a bright buff in order to avoid too great a variance between the glazed tile and ceiling areas. Table tops are mahogany, and waste cans light blue. All colors were chosen for their value under artificial light.
In average shop, a maximum of white ceiling and side wall should be provided to conserve the light from natural sources. Under no circumstances should sash be painted black or deep gray because such dark colors may readily absorb up to 47 percent of the active light entering such areas. Sash should preferably be painted white or ivory.
The five-foot dado, or lower wall panel, may be a light tan or green, preferably on the gray-green or jade-green side for softness and to kill the very appreciable but generally ignored "ground light" reflected upwards to the eyes of machine operators. This ground ligth may be a definite accident hazard.
All starting equipment, clamp-rack knobs, machine-table edges, and guards should be painted a bright red or scarlet. This becomes doubly effective on machine-table edges when they carry a narrow stripe of bright yellow along the center of the red.
The bodies of all machines may be a light to medium chome green. For this use white oilproof machine enamel shaded to a light ivory by stirring in a slight amount of French och er ground in oil; then shaded light pearl gray by adding a trace of black enamel; then to a soft, bright shade of jade green by adding medium chrome green in oil. if five gallons or more are needed, any reputable paint manufacturer will make up a jade-green machine enamel to suit.
Again, the machines may be a soft, light straw or tan, trimmed with bright green and scarlet. Avoid heavy, deep colors as they are as deadly as the customary black and "machinary gray," which make the shop dull and dreary.
In most cases the machines have been painted by the manufacturer on frames well filled, puttied, sanded, and surfaced before applying the enamel. Where long service or hard usage has chipped or dented the surface, the machines must be serviced before painting. Wash with a trisodium-phosphate solution, using ½ lb- of powder to a 15-gt pail of hot water. Rinse well, then wipe down with rags saturated with denatured alcohol to remove the last traces of grease, especially in the neighborhood of berings. Do not use gasoline because this would spread a layer of oil over the entire surface and destroy adhesion.
Apply a coat of sanding surfacer sold by the manufacturer of your machine enamel and handled according to directions on the can. Let dry hard, then putty up all dents, chips, and rough areas, using a putty-knifing glaze applied according to directions. Dry hard; the time will vary with the glaze.
A glaze can be made by hand from one third white lead paste in oil, two thirds white lead paste in oil, two thirds dry whiting, and enough machine enamel to make it work smoothly under the glazing knife.
When the putty has dried hard, sand the entire job smooth and level with 2/0 waterproof abrasive paper and water. Wipe clean and let dry. Apply a second surfacer coat if desired.
The enamel may then be brushed on or sprayed. Let the enamel dry hard enough to resist thumb-mail pressure, then apply a second coat.