Common Painting Defects
♦ Blistering : This is caused due to loss of adhesion and due to moisture entrapped between the surface & paint film. To avoid this allow the surface to dry thoroughly before painting and keep adequate interval between 2 subsequent coats.
♦ Cracking : This occurs due to contraction of film. Cracking is caused due to incompatibility of the paint with improper thinner or when the Paint is applied on non suitable primer. So to avoid cracking always use proper thinner suitable for the particular paint to be applied.
♦ Peeling : Whenever ther is moisture or dampness or improper surface preparation. This can be avoided by proper surface preparation and painting in dry conditions.
♦ Blooming : Loss of gloss occurs due to humidity on the surface and climatic conditions, or sometimes due to overuse of thinner. To avoid this always use sufficient thinner only to thin down the paint to spraying consistency.
♦ Running or Sagging : If the paint coat is very thick the film may start running down and result in sagging. Avoid thick coats.
♦ Wrinkling : This occurs when a airdrying paint is stoved at elevated tempratures. To avoid this always use Stoving Paint for drying in ovens.Air drying paints are to be air dried or can be stoved at 60-70 degrees C. for 1 Hr.
♦ Brush Marks : This occurs due to incorrect application or due to improper, brush, or due to applying quick drying paint by brush. To avoid this always use spray gun for application of quick drying paints.
♦ Patchiness: Whenever the surface is absorbent like wood or porous surface patches appear while painting. To avoId this apply sufficient coats of primer so as to fill the pores in the surface and allow the primer to dry thoroughly before applying finish coats.
