Ultra-comprehensive paint FAQs and solutions (recommended collection)

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in the paint repair operation, if the correct operation method, orange peel and bubbles and other common paint problems can be mostly avoided. However, due to the more process of repair paint work, the chance of paint problems is still very high. Analysis of the cause of the problem, usually due to putty layer or primer layer mishandled, paint process lack of control, poor working environment, and paint composition deviation. If a problem is found during the painting process, the operation can be stopped and appropriate measures taken immediately, depending on the problem, or it can wait between the end of the painting process before processing.Here is to analyze the paint defects and treatment methods commonly found in painting operations.1, moist foaming
evenly distributed hemp-shaped small bubbles, different sizes, in very humid and hot conditions prone to appear. These bubbles disappear when the air humidity decreases and the paint film becomes flat.​(1) Cause (1) paint, medium coating, primer and substrate between each other is not enough adhesion, may lead to blistering.
(2) paint is relatively permeable. Under very humid and hot conditions, water penetrates into the paint film in liquid form and then through the paint film in the form of steam, thus forming moist bubbles.​(2) Correction method (1) in wet weather can only use dry grinding, keep compressed air dry, to ensure that the spray surface before spraying completely dry.​(2) Do not place the paint parts in a hot and humid environment until they are completely dry.​(3) When the bubble is not cracked, you can wait for the moisture to evaporate so that the paint film returns to its original condition, in serious cases must be thoroughly polished after re-spraying, painting to bare metal re-spray is the best choice.2, pollution foamingalso known as bubbles or "tweezers", that is, the surface of the paint layer irregular foaming situation.​(1) The main cause (1) is substrate pollution, painting before not carrying out proper cleaning and preparation. ​ (2) Contamination from gas supply pipes or spraying tools. ​ (2) The correction method (1) cleans the spray surface and completely removes wax, grease and polishes and other substances. ​ (2) Ensure the cleaning of compressed air, air supply pipes and spray guns and other tools. ​ (3) If the tweezers have been produced, gently polish the surface, pay attention not to wear through the paint film, re-spray. If the condition is serious, polish to bare metal and re-spray. 3, paint sprayed, paint has foreign or dirty spots, dust or dirt is wrapped in paint film. (1) cause (1) spraying workshop is not clean, such as paint room on the interior surface is not laid filter cotton, filter cotton on the roof for a long time has not been replaced. ​ (2) Compressed air is not clean, paint operators do not wear special work clothes, spray surface is not clean. ​ (3) The paint is not effectively filtered before spraying. (2) correction method (1) to keep the paint workshop clean, regularly replace the paint room filter cotton, strictly prohibited in the paint room grinding atomic ash. ​ (2) Ensure that compressed air is clean and replace the filter regularly. Clean the spray surface with compressed air or a dust cloth before spraying. ​ (3) Properly seal and store the paint, the paint should be fully stirred before spraying, and filtered after use. ​ (4) If there are already dust spots, should be polished to a smooth surface and re-coated. For lighter dust points, fine sandpaper should be polished and polished. 4, feather edge cracking paint film in the feather edge around cracking, in a very short period of time after spraying paint will appear. ​ (1) Cause (1) excessive dilution or use of inferior thinners. ​ (2) In grinding the beveled edges used thick sandpaper, and paint before not proper treatment, the solvent in the paint into the sandpaper trace erosion paint film. ​ (3) The paint sprayed on the inner coating is too thick or too wet, and the solvent in the paint does not have enough time to evaporate outwards. ​ (4) Old paint film or previously patched defects appear, or the use of too much atomic ash. ​ (2) The correction method (1) correctly polishes the feather edges, smooth and smooth transition, and avoids any sharp corners and levels. ​ (2) According to the specific situation of the workshop, according to the requirements of the use of thinners and the use of the correct dilution ratio. ​ (3) Do not blow dry spray after the paint film, because this can only reach the surface dry. ​ (4) In the event of cracking, the surface of the lacquer film should be polished and re-sprayed. 5, also known as silver powder flowering, which is a common problem of silver powder and pearl primer. The paint film shows signs of being knocked, with some dark circles surrounding light silver powder or shades of color. If it is in primer paint, this phenomenon is often not discovered until varnish has been sprayed. ​ (1) Cause (1) Silver powder paint is composed of a variety of different pigments and aluminum powder, in the thick or damp paint level spray silver powder, will make silver powder in silver powder can not be leveled, thus forming a pattern. ​ (2) When the temperature is too low and the silver powder is sprayed, the silver powder will be in a humid or liquid state for a long time, and the silver powder will accumulate in piles. ​ (3) When spraying silver paint, if the air pressure used is low, or the spray gun and surface plate is closer, then when the paint surface reaches the work surface, too little solvent volatility will lead to the formation of a damp paint film, easy to lead to the phenomenon of marking. ​ (4) A diluent with a slow evaporation rate was used, or the thinner was used excessively. (2) correction method (1) dilute the silver paint according to the requirements and master the correct spraying techniques, such as the distance between the spray gun and the spray surface and the speed at which the spray gun moves. ​ (2) Do not apply excessive thick wet paint. When necessary, raise the temperature of the paint workshop appropriately and extend the time between the paint films. ​ (3) If the plaque has been produced, it is recommended to re-spray with the correct dilution ratio and construction techniques. If the markings are produced in a primer coated with varnish, the paint film needs to be peeled back and repainted. 6, paint surface subsidence the area of repair, paint surface forms a "lake" shape appearance. ​ (1) Cause (1) When spraying multi-layer paint, the previous layer of paint is not thorough enough. ​ (2) Atomic ash subsidence, but spraying low-gloss medium primer is not easy to be found, and spraying high-gloss paint, paint subsidence phenomenon appears. ​ (3) In a short period of time sprayed with multiple layers of wet paint, medium paint and paint between the layers of stationary time is not long enough. ​ (2) Correction method (1) All atomic ash layers should be completely dry, especially when the weather is bad or the temperature is low. ​ (2) Do not thickly apply primer and paint wet paint film, should be in accordance with the requirements of the control layer between the sit-in time. ​ (3) Do not dry the wet paint film surface by air, as this may cause only the surface to dry, and the solvent inside the paint film is not completely volatile. ​ (4) When the lacquer film subsidence occurs, polish to a smooth surface and then re-spray. 7, pinholes also known as pits, that is, the appearance of paint film on the dense small holes. (1) cause (1) the compressed air used for spraying contains moisture, or the wrong type or amount of thinner is used in the paint. (2) excessively thick wet coating, or force drying with a hairdryer, or spray workshop temperature is too high or too low. (2) correction method (1) the exhaust valve of the air compressor that provides the gas source should be opened daily to allow the aggregated water to flow out. ​ (2) to avoid excessive thick coating, medium film thickness to ensure proper solvent volatility. Do not blow dry wet paint surfaces, which may cause surface epithets or solvent retention in the membrane. ​ (3) Strictly follow the drying rules. Select the correct thinner and dilute it according to the recommended proportion. ​ (4) Use the correct spray gun and adjust the pressure to ensure that the atomization effect is good. ​ (5) If the pinhole occurs, polish to level and repaint. 8, paint pigment particles are no longer affected by the role of adhesive, paint film surface presents powder, passivation, fading and loss of luster. ​ (1) Cause (1) Because the paint film for a long time exposed to strong sunlight and other climatic conditions, pigment particles in the paint aging or loose, resulting in the paint surface gradually powdery peeling off. ​ (2) The use of the wrong thinner, so that the durability of the paint layer is impaired. ​ (3) The paint is not mixed evenly. ​ (2) The correction method (1) select the appropriate thinner and mix the paint evenly before spraying. ​ (2) Mild powdering can be polished to remove, more serious cases need to be polished with crude wax, heavy powdering needs to be re-patched spray. 9, acid erosion appearance of rough spots, spot edges because of acid erosion into the paint film, sometimes the paint film color changes and make the paint uneven. ​ (1) Cause (1) asphalt on the road surface, insect carcasses and industrial pollutants and other acidic substances corrosion, or in the maintenance of vehicles spilled on the paint surface of the brake fluid and other grease, will cause acid erosion. ​ (2) The paint film is cleaned before it is dry, or an unsuitable cleaning agent is used. (3) The old paint film contains contaminants or polishes, and is not thoroughly treated before re-spraying, can cause acid erosion of the new paint film. ​ (2) The correction method immediately removes the above-mentioned polluting substances from the paint surface, polishes the acid erosion with crude wax, and in severe cases needs to be polished and re-sprayed. 1
0, striped
also known as plaques or shadows. The surface of the lacquer layer appears the color of the difference, often in parallel, silver powder paint and pearl paint appear the highest chance. ​ (1) Cause (1) spray gun spray paint fan-shaped mid-edge paint too much, and the middle paint is too little, the possible cause is that the compressed air pressure is too large, spray gun dirt or nozzle adjustment is improper, should reduce the compressed air pressure or narrow the spray fan. ​ (2) The spraying technology is poor, the distance between the spray gun and the spray surface often changes or overlaps unevenly when spraying, the distance between the spray gun and the spray surface should always be consistent during the spraying process, and maintain 50% overlap. ​ <br