Many problems occur due to improper following of set procedures. A good quality paint surface depends upon the right use of following:

• Type of thinners
• Viscosity of paint
• Atomization of Paint
• Operator skill
• Curing Time

Some common problems are as below:

Blistering


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Lifting of the paint film from the underlying surface, which appears as paint bubbles or paint blisters in the mixture, is usually caused by heat, moisture, or excessive moisture in the paint mixture.

Chipping



Surface impact, primer without sealing before applying topcoat, exposure to harsh conditions, Component “A” and Component “B” not uniformly mixed, a coating applied over a previously cracked finish or unstable substrate, excessive total film thickness.

Delamination


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Contaminated surface, metal conditioner, and/or appropriate primer was not used, the insufficient flash-off time between coats, poor quality sanding, incorrect film build-too heavy, incorrect Spray Technique, a coating applied too dry or too heavy, insufficient flash off time between coats (and or between primer and topcoat).

Mottling



Improper equipment - a type of gun, size of the nozzle, improper gun settings, Incorrect spray technique, Holding spray gun too close to surface, Uneven spray pattern, Application too heavy  Wrong thinner/reducer for shop temperature, Component ''A'' and Component ''B'' not thoroughly mixed.

Orange Peel


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Viscosity too high  Gun air pressure too low (causing lack of atomization), Primer or sealer applied not smooth Wrong thinner/reducer, Incorrect spray technique, Holding gun too far from the surface, the Wrong amount of thinner or reducer used - not enough, Poor quality sanding.