COVERING CAPACITY 



335 



ing the larger the surface covered per unit of paint. To obtain any 

 given thickness of paint therefore requires practically the same amount 

 of paint whatever its pigment may be. The claims often urged in favor 

 of a particular paint that it has a large covering capacity may mean 

 nothing but that an excess of oil has been used in its fabrication. An 

 idea of the relative amounts of oil and pigment required, and the cov- 

 ering capacity of different paints may be obtained from -the following 

 table. 



AVERAGE SURFACE COVERED PER GALLON OF PAINT.* 



Light structural work will average about 250 square feet, and 

 heavy structural work about 150 square feet of surface per net ton of 

 metal. 



It is the common practice to estimate J^ gallon of paint for the 

 first coat and ty& gallon for the second coat per ton of structural steel, 

 for average conditions. 



Applying the Paint. The paint should be thoroughly brushed 

 out with a round brush to remove all the air. The paint should be 

 mixed only as wanted, and should be kept well stirred. When it is 

 necessary to apply paint in cold weather, it should be heated to a tem- 

 perature of 130 to 150 degrees Fahr. ; paint should not be put on in 

 freezing weather. Paint should not be applied when the surface is 

 damp, or during foggy weather. The first coat should be allowed to 

 stand for three or four days, or until thoroughly dry, before applying 



*Pencoyd Handbook, page 293. 



