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Ali Hamza
Ali Hamza
Mechanical
19 Jan 2019

What is the surface application of paints??

PAINTING PLASTERED SURFACE, Painting New Surfaces

• Surface Preparation: Paint cannot take care of construction defects. Before applying the paint it is ensured that the surface is free from dust, dirt, loose matter, grease etc. and is rubbed with a sand paper, to provide a mechanical key between surface and paint for satisfactory adhesion.

• Sequence of Painting: The primer (first coat) is applied with brush or spray on the prepared surface. It should be thinned with water or thinner in the recommended manner and proportion before application. After drying it is rubbed with emery paper.

• Dents and cracks, if any, are filled with putty using a knife applicator. Putty (paste from chalk etc) should not be applied thick. If the required thickness is large, it should be applied in two coats. 

After the putty has dried, the whole surface is rubbed down well in order to smoothen the putty and provide a mechanical key to  the finished coats. 

• Two or three finish coats are applied. Each coat is allowed to dry before the application of next coat. 

• Painting Old Surfaces

• The procedure depends on the state of the existing coating. If any of the defects discussed below is very much pronounced it  is completely removed and the surface is painted as a new  surface. 

• Chalking: Clean the surface; rub with an emery paper so that the chalk is removed. Apply one or two finish coats. 

• Efflorescence, Blistering, Cracking and Flaking: Scrap off the old paint from affected areas. Touch up with primer and  apply one or two finish coats on effected areas. Rub the  entiresurface and apply the finish coats.