{"id":7269,"date":"2022-05-26T12:41:15","date_gmt":"2022-05-26T10:41:15","guid":{"rendered":"https:\/\/policolor.ro\/frequent-defects-in-painting\/"},"modified":"2022-05-26T12:41:15","modified_gmt":"2022-05-26T10:41:15","slug":"frequent-defects-in-painting","status":"publish","type":"page","link":"https:\/\/policolor.ro\/en\/frequent-defects-in-painting\/","title":{"rendered":"FREQUENT DEFECTS IN PAINTING"},"content":{"rendered":"
\n
\n
\n

Gathering<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nLifting or swelling (creasing) of the freshly applied layer.\n\n

CAUSE:<\/strong><\/p>\nToo long drying time when working with wet-on-wet products.\nRepainting some solvent-sensitive paints (TPA-acrylic thermoplastics) with non-indicated products.\nPaints applied as insulators are applied in too thin layers or are sanded too deeply.\n\n

How to avoid:<\/strong><\/p>\nAlways respect the recommended cooling times (don’t leave too long).\nDo a solvent test before application and use the appropriate materials for the recommended layer thickness.\nApply the products to the recommended layer thickness.\n\n<\/div>\n<\/div>\n

\n

Transpiration<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nThe slow evaporation of the solvent (sweats) from the freshly applied paint layer.\nThis leads to perspiration of the paint layer, which leads to reduced gloss or contours.\n\n

CAUSE:<\/strong><\/p>\nInsufficient drying between layers in the case of complete painting or the application of filler in too thick layers.\nApplication of loading or filling materials in too thick layers.\nSoftening and swelling of substrates sensitive to solvents.\nAdding the wrong amount of hardener to the putty or filler.\n\n

How to avoid:<\/strong><\/p>\nAlways respect the recommended layer thickness and the recommended drying times.\nDo a solvent test before application. Apply the filler in normal layers with air time between layers to create an isolation from the solvent-sensitive substrate. Do not apply putty to old solvent-sensitive paint.\nRespect the mixing rations.\n\n

Remedy<\/strong><\/p>\nSand the entire affected area and rebuild the system with suitable products.\n\n<\/div>\n<\/div>\n

\n

Blistering<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nIn wet weather, a small amount of vapor is absorbed into the paint layer and then evaporates during the drying process.\nDefective processing of the filler will leave salts on the surface. These salts cause a local concentration of salt solution that will penetrate the paint layer later applied in the form of basicutes. These chips can appear in different sizes and locations, either on certain areas or in the entire paint film.\n\n

CAUSE:<\/strong><\/p>\nThe surface to be painted (filler, sheet, etc.) was not sufficiently cleaned. Contamination with salt residues, hand sweat, dirty water from wet sanding, were left on the surface to be painted or between layers.\nWet sanding operations without sufficient time left for the water to evaporate before applying the paint.\nClimatic conditions in the painting booth during painting.\n\n

How to avoid:<\/strong><\/p>\nClean the surface well before painting with clean water. Change the water regularly during wet sanding. Try to sand as dry as possible. Allow enough time for the water to evaporate (approx. 2 hours at 20\u00baC) when sanding wet. Dry sand as much as possible, especially polyester putties. \n \nMake sure that the paint booth is dry before painting.\nIn cold and wet weather, put the cabin on the drying cycle shortly before starting painting.\n\n

Remedy:<\/strong><\/p>\nSand and completely remove the defect up to the layer in which it appeared. Then redo the entire painting system (primer, filler, paint). \n\n<\/div>\n<\/div>\n

\n

Bleeding, spotting<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nBleeding is the staining or bleeding of a dye from the previous substrate into the upper paint layer. It is observed as a stain or discoloration in the paint layer (often red or yellow). The excess of peroxide hardener in polyester putty can cause this defect due to the reaction with the pigments in the paint. \n\n\n

Cause:<\/strong><\/p>\nThe soluble pigments or dyes in the old paint are dissolved by the solvent in the new paint. Staining can occur when the excess peroxide hardener from the polyester products reacts with the pigments from the other products, leading to the appearance of yellow-brown stains. Blue and green colors are especially vulnerable to this phenomenon.\n \nBitumen or tar residues on the surface.\n\n

How to avoid it:<\/strong><\/p>\nPerform a solvent test on the old paint to check for soluble pigments. Always respect the mixing ratios indicated for the mixture with the hardener and mix until complete homogenization with the putty. Before painting, make sure that the surface is cleaned of possible contamination with bitumen or tar.\n\n\n\n

Remedy:<\/strong><\/p>\n\nTo fix such a defect, the respective surface must be insulated with an intermediate product applied as an insulator. If the stain is deep, the surface must be sanded down to the substrate where it appeared and the entire system repainted with suitable materials. \n\n<\/div>\n<\/div>\n

\n

Poor covering power<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nThe substrate is visible through the layer of applied paint.\n\n

Cause:<\/strong><\/p>\nFor certain shades, the indicated colored intermediate layer (undercoat) was not applied. The applied paint was over diluted. Paint applied in too thin layers. Basic colors not mixed enough.\n\n\n\n\n

How to avoid:<\/strong><\/p>\nAlways apply the colored intermediate layer (undercoat) indicated in the recipe.\nRespect the dilution ratios.\nApply the paint in the recommended layer thickness.\nMix the base colors before preparing the paint.\n\n

Remedy:<\/strong><\/p>\nAfter drying, it is sanded and repainted.\n\n<\/div>\n<\/div>\n

\n

Low gloss<\/h3>\n
\n\n

Cause:<\/strong><\/p>\nSlow evaporation of the solvent from the previous paint layer.\nApplying paint in too thick layers.\nAtmospheric factors \u2013 the action of sulfur dioxide, nitrogen oxide in combination with atmospheric humidity or UV radiation.\nIncorrect amount of hardener in 2k paints.\n\n

Improper treatment after painting:<\/strong><\/p>\nIncorrect polishing (too aggressive polish or polish in the sun).\nWashing with very rough or worn brushes.\nAggressive washing liquid.\nRemoving the painted car too early in the ambient environment. Fresh paint applied in too thick layers is sensitive to the humidity in the air.\nInsufficient ventilation during painting or during drying.\n\n

How to avoid:<\/strong><\/p>\nSee “low evaporation”.\nApply the paint in the recommended layer thickness.\nPay attention to atmospheric factors.\nRespect the mixing rations.\nRespect the mixing rations.\nObserve the recommended drying times and layer thickness.\nCheck the air circulation in the paint booth and the cabin filters.\n\n

Remedy:<\/strong><\/p>\nTry to polish the respective area. If it doesn’t help, it will be repainted.\n\n<\/div>\n<\/div>\n

\n

Poor adhesion<\/h3>\n

Definition:<\/strong><\/p>\nWeak adhesion can manifest itself in 2 ways:\nEither the whole system falls apart;\nWeak adhesion is manifested only between layers.<\/div>\n

<\/div>\n

Cause:<\/strong><\/p>\nSubstances that can cause poor adhesion are left on the surface (silicone, oil, fats, protective wax).\nApplying an inappropriate primer or filler.\nInsufficient sanding on the surface.\nThe primer or paint were applied in too thin layers.\nDrying in defective conditions.<\/div>\n

<\/div>\n

How to avoid:<\/strong><\/p>\nTo avoid lack of adhesion to the substrate, observe the following:\nUse a primer or filler indicated for the respective substrate.\nApply the products according to the technical instructions.\nClean and degrease the surfaces before any product application.<\/div>\n

<\/div>\n

Remedy:<\/strong><\/p>\nCompletely remove the layers with low adhesion. Sand and degrease the surface.\nRepaint using appropriate products.<\/div>\n<\/div>\n

\n

Solvent bubbles<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nCracks due to the penetration of the solvent from the lower layer into the upper one.\n\n

Cause:<\/strong><\/p>\nLayers applied too thickly.\nHardener or thinner too fast.\nHardener or thinner too fast.\nDrying time before drying with the infrared lamp is too long.\nInsufficient distance between the painted object and the IR lamp.\nAeration time too short when using wet-on-wet application products.\n\n

How to avoid:<\/strong><\/p>\nObserve the recommended layer thickness.\nUse the recommended hardener and thinner depending on the working temperature.\nLeave the recommended airing times between layers.\nLeave the recommended airing times before drying with IR.\nKeep the recommended distance from the piece when drying with IR.\nLeave the recommended airing times between layers.\n\n

Remedy:<\/strong><\/p>\nTo remedy this defect, it must be sanded down to the layer in which they appeared and then repainted.\nIf these small bubbles are not completely removed, they will lead to the appearance of pitting when the next layer of paint is applied.\n\n<\/div>\n<\/div>\n

\n

TINGLINGS<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nSmall pits or craters in the freshly applied paint as a result of solvent bubbles not completely removed from the old paint.\n\n

Cause:<\/strong><\/p>\nSolvent bubbles present in the substrate on which the paint is applied.\n\n

How to avoid:<\/strong><\/p>\nEither they are sanded and the bubbles are removed, or they are plugged.\n\n

Remedy:<\/strong><\/p>\nPunctures are repaired by sanding the surface or filling them by applying some filling products.\n\n<\/div>\n<\/div>\n

\n

Craters<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nCircular craters with a diameter from 0.5 mm to 3 mm.\n\n

Cause:<\/strong><\/p>\nThe main cause is the presence of substances on the surface such as: oil, fat, wax or silicone.\n\n

These substances can come from:<\/strong><\/p>\nPersonal \u2013 stains on work cloths, traces on gloves, hair lotions, perspiration.\nPaint booth \u2013 Lubricating oils from certain components, substances for treating plastic parts, insulators, dirt on the booth floor.\nPaint \u2013 Incorrect use of anti-silicone additives, impurities from transport or storage.\nPart \u2013 Residues from plastic parts treatment agents, oil from welding fume insulating products.\nTools and auxiliary products \u2013 Inappropriate degreaser, masking tape adhesives.\nAmbient environment \u2013 \u200b\u200bExhaust gases, welding fumes, dust from insulating construction materials.\n\n

How to avoid:<\/strong><\/p>\nUsing only silicone-free products in and near the paint shop and cleaning and degreasing the surfaces to be painted.\n\n

Remedy:<\/strong><\/p>\nSanding up to the layer where the crater appeared and repainting.\n\n<\/div>\n<\/div>\n

\n

Scratches from washing brushes<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nTraces of parallel scratches visible especially on dark colors. The surface can also lose its gloss.\n\n

Cause:<\/strong><\/p>\nManual or automatic washing with too rough or very worn brushes.\nPrewash too dry or with too little water.\nWashing the car too quickly after it has been painted.\n\n

How to avoid:<\/strong><\/p>\nUse normal brushes for washing the car.\nWater the car abundantly before washing.\nWater the car abundantly before washing.\n\n

Remedy:<\/strong><\/p>\nPolish the scratches with abrasive polish and then with gloss polish.\n\n<\/div>\n<\/div>\n

\n

Coating<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nThe decomposition of the binders in the painted surface leads to the discoloration of the paint pigments, so that the red and yellow colors become whitish, and the blue becomes bronze.\n\n

Cause:<\/strong><\/p>\nUsing an inappropriate hardener or in the wrong amount.\nThe paint layer applied in too thick layers.\nThe action of external factors (pollution with sulfur dioxide or nitrogen oxides in combination with high humidity).\nDefective treatment after painting.\nIncomplete repair of a previous chalking.\n\n

How to avoid:<\/strong><\/p>\nAlways use the indicated strengtheners in the recommended quantities.\nApply the paint in the recommended layer thickness.\nProtect the car from harmful external factors.\nDo not subject freshly painted surfaces to harsh treatments.\nMake sure that the previous chalking has been completely removed by sanding down to the layer in which it appeared.\n\n

Remedy:<\/strong><\/p>\nTry to polish the affected surface with abrasive polish and then with gloss polish.\nIf it does not help or if the defect reappears after a few weeks, then it must be removed by sanding up to the layer in which it appeared and then repainted.\n\n<\/div>\n<\/div>\n

\n

Peeling paint<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nTotal removal of the entire paint film.\n\n

Cause:<\/strong><\/p>\nIncomplete cleaning of the plastic substrate.\nInsufficient sanding to create adhesion.\nUsing an inappropriate degreaser.\nThe plastic part was not tempered before painting.\nNo adhesion primer was used.\n\n

How to avoid:<\/strong><\/p>\nWash the piece with water and detergent to remove substances that are only soluble in water. Then degrease with degreaser to remove solvent-soluble contamination.\nAlways sand with the recommended abrasive before application.\nUse the indicated degreaser.\nTempering is the operation of “removing” the substances from the plastic pores by heating (1-2 hours at 60\u00ba C). The plastic parts with a porous surface must be tempered to remove from the plastic the “treating agents that entered the pores of the plastic during the treatment operation. This problem can occur with PUR plastics. Clean the plastic with degreaser before and after tempering.\nAlways use plastic adhesion primer.\n\n

Remedy:<\/strong><\/p>\nRemove all peeling paint completely and repaint the entire system accordingly. Do not use solvent to remove the paint. This solvent can destroy the plastic.\n\n<\/div>\n<\/div>\n

\n

Cracks<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nCracks or breaks in the form of a line in the paint layer.\n\n

Cause:<\/strong><\/p>\nNo elasticizing additive was added to the paint applied to the spoiler.\nThe thickness of the entire paint system is too high.\n\n

How to avoid:<\/strong><\/p>\nUse an elasticizing additive when applying plastic paint (see technical sheet).\nKeep the recommended layer thickness for each product.\n\n

Remedy:<\/strong><\/p>\nRemove, if possible, by sanding, the paint and then redo the painting system.\nDo not remove the paint from the plastic parts with the help of aggressive solvents (it can destroy the plastic).\n\n<\/div>\n<\/div>\n<\/div>\n

\n
\n

Pricks (pores)<\/h3>\n
\n\n

<\/p>

Definition:<\/strong><\/p>\nSmall holes in the painted surface due to the pores on the plastic surface.\n\n

Cause:<\/strong><\/p>\nDefects in the manufacture of plastic parts.\n\n

How to avoid:<\/strong><\/p>\nCheck very carefully the surface of the plastic parts before painting.\n\n<\/div>\n<\/div>\n

\n

LEAK<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nLeaks of freshly applied paint.\n\n

Cause:<\/strong><\/p>\nPaint viscosity too low.\nThe part to be painted is too cold (it was not conditioned before painting).\nThe paint was applied too thickly.\nToo many layers applied.\nHardener or thinner too fast.\nPainting distance too short.\nThe nozzle of the gun used is too large.\nDefective painting technique.\n\n

How to avoid:<\/strong><\/p>\nKeep the application viscosity.\nApply the paint on parts that have been conditioned (the part has the temperature of the environment).\nRespect the painting distance as well as the nozzle indicated for each product.\n\n

Remedy:<\/strong><\/p>\nThe removal of leaks is done by sanding with a very fine abrasive or by polishing.\n\n<\/div>\n<\/div>\n

\n

Metamerism<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nIt is an effect in which a color can appear in various shades in various light conditions. The most common case is when two colors match in daylight, but are different in artificial light.\n\n

Cause:<\/strong><\/p>\nThe pigment in the prepared paint does not have the same composition as the paint on the car.\nPreparing a paint that differs from the one in the recipe without checking the color under various light sources.\nTinting the paint applied with a paste that is not in the original recipe.\n\n

How to avoid:<\/strong><\/p>\nWhen preparing a new shade that is not in the recipe, the metamerism must be checked through colorimetric tests and measurements.\nFor shades that are in the recipe, they must be checked in various light sources.\nMake shades only with the pasta in the recipe.\n\n

Remedy:<\/strong><\/p>\nSmall metamerism effects can be solved by the blend-in or loss technique.\n\n<\/div>\n<\/div>\n

\n

Orange peel<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nThe appearance of the paint on the surface is similar to that of an orange peel.\n\n

Cause:<\/strong><\/p>\nFar too long painting distance.\nPainting pressure too low.\nLayer thickness too small.\nThe viscosity of the paint is too high (the paint is too diluted).\nThe hardener and\/or thinner used are too fast for the application conditions and for the size of the surface to be painted.\nGun nozzle too small.\nToo long drying time between layers.\n\n

How to avoid:<\/strong><\/p>\nKeep the recommended distance from painting.\nPaint at the indicated pressure.\nAlways apply full coats.\nKeep the recommended application viscosity.\nChoose the right hardener for the painting conditions and the size of the parts to be painted.\nUse the recommended gun nozzle.\nLeave the recommended aeration times.\n\n

Remedy:<\/strong><\/p>\nIf the defect is minor, polish the surface.\nIf the defect is major, sand the surface and then repaint.\n\n<\/div>\n<\/div>\n

\n

Edges (contours)<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nEdge contouring visible in the final paint around the surfaces where putty or filler has been applied.\n\n

Cause:<\/strong><\/p>\nInsufficient drying of the filler or putty.\nSoftening the layer applied to the meeting area where the filler layer met the old paint on the car or sheet. Or the lost sanding of the edges was not done properly.\nImproper paint system applied over TPA (thermoplastic acrylic) or NC (nitrocellulosic) paints.\nSurfaces sanded down to sheet metal not properly insulated before applying paint and varnish.\nPolyester putty applied over the old paint in a thick layer.\n\n

How to avoid:<\/strong><\/p>\nRespect the recommended drying times. Drying with IR lamps reduces the risk of contouring due to the drying method (from the sheet to the last layer).\nBefore starting the repair, do a solvent test (with an acrylic or nitro solvent) to check the sensitivity of the old paint to solvents. When sanding, make sure that you have respected the sanding granulations for sanding the substrate before applying the following product:\nP80\/150-for putty.\nP240-for.primer\/filler.\nApply the solvent-free filler layer in a thin layer to isolate solvent-sensitive surfaces.\nBuild a suitable painting system: putty-filler-paint-varnish.\nDo not apply polyester putty in thick layers on the old paint. Apply putty only to the clean board and leave a clean edge of the board up to the old paint.\n\n

Remedy:<\/strong><\/p>\nThe respective surface is sanded and repainted accordingly.\n\n<\/div>\n<\/div>\n

\n

Cracks (crocodile skin look)<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nCracks of various lengths, depths and widths.\n\n

Cause:<\/strong><\/p>\nThe use of polyester putties, washprimers, synthetic enamels directly on TPA (thermoplastic acrylic) paints.\nNo hardener has been added to 2k products.\nApplication of polyester putty over washprimer primer.\nToo aggressive drying with UV lamps, large temperature fluctuations.\nAeration times too short when applying wet-on-wet products.\nThe film thickness of the entire applied system is too high.\n\n

How to avoid:<\/strong><\/p>\nDo not apply polyester putties or washprimer-type reactive primers over TPA paints.\nObserve the mixing ratios for the 2k products.\nDo not apply polyester putty over washprimer reactive primer.\nFollow the instructions for use of the UV lamps.\nLeave the recommended aeration times.\nObserve the recommended film thickness.\n\n

Remedy:<\/strong><\/p>\nThe respective surface is sanded down to the substrate where the defect no longer appears and the corresponding system is restored.\n\n<\/div>\n<\/div>\n

\n

Search, shriveled appearance<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nThe surface of the applied paint is textured, with irregularities. This defect occurs when the final paint dries faster than the ones applied below it. It usually appears in the presence of synthetic enamels.\n\n

Cause:<\/strong><\/p>\nSynthetic enamel applied too thick.\nNo drying solution was added to the synthetic enamel.\nUnfavorable drying conditions (temperature too high).\n\n

How to avoid:<\/strong><\/p>\nObserve the recommended number of layers and the recommended film thickness.\nMake sure that the drying solution will be added to the recipe.\nDry at the optimal temperature, not too high.\n\n

Remedy:<\/strong><\/p>\nFor small defects, dry the painted surface properly, sand until the substrate is perfectly hardened and then repaint.\nFor large defects, the entire paint system is stripped and redone accordingly.\n\n<\/div>\n<\/div>\n

\n

Sanding marks, sanding scratches<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nTraces of sanding from the previous substrate.\n\n

Cause:<\/strong><\/p>\nThe previous substrate was sanded too coarsely. The scratch thus formed is too deep to be covered by the product applied over it.\nThe drying times of the primer or filler were not respected. Thus, the sanding marks will become visible during the application of the final paint due to the softening of the filler layer, and then surface creasing will appear during drying.\nThe filler layer was applied too thin to cover the scratches.\nFailure to follow the sanding steps or a faulty sanding technique.\n\n

How to avoid:<\/strong><\/p>\nFollow the sequence of sanding steps.\nRespect the drying times.\nRespect the layer thicknesses.\nAlways place the sole of the sander on the workpiece and then turn on the sander.\n\n

Remedy:<\/strong><\/p>\nSand down to the substrate where the scratches appeared and repaint again.\n\n<\/div>\n<\/div>\n

\n

Dust inclusions<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nSmall particles of various origins (dust, fluff) present in the paint film.\n\n

Cause:<\/strong><\/p>\nThe substrate was not cleaned before painting.\nThe filter system of the paint booth is dirty, the air supply hoses are dirty, etc. Body\nContamination of finishing areas with air from preparation areas.\n\n

How to avoid:<\/strong><\/p>\nDegrease and clean before painting.\nEnsure the correct maintenance of the paint booth. Body\nMake sure that the finishing areas of the paint are separated from the preparation areas.\n\n

Remedy:<\/strong><\/p>\nFor minor defects it is polished.\nFor major defects, sand down to the layer where the contamination originates and repaint.\n\n<\/div>\n<\/div>\n

\n

Gassing<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nGases from painting that will reach the parts attached to the painted one or that are not absorbed by the previously applied paint.\n\n

Cause:<\/strong><\/p>\nGases are not absorbed in the previous layer due to the use of a hardener or thinner too fast for the painting conditions or too fast for the size of the painted surfaces.\nDefective painting technique.\n\n

How to avoid:<\/strong><\/p>\nSelect the right hardener and thinner for the temperature of the environment in which it is painted and for the size of the painted surface.\nUse the recommended painting technique.\n\n

Remedy:<\/strong><\/p>\nIt is polished first with an abrasive polish and then with a gloss one.\n\n<\/div>\n<\/div>\n

\n

Throwing stones<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nMechanical damages in the paint layer due to stone hits on the road.\n\n

Cause:<\/strong><\/p>\nHitting stones of various sizes from the roadway.\nDepending on the force with which these stones hit the paint system, damages may appear in the paint layer or in the primer-filler layer up to the clean sheet.\nThe moisture will penetrate the paint film and detachments of the entire paint system may occur.\n\n

How to avoid:<\/strong><\/p>\nThere is no total protection against stone blows.\nFor the surfaces that are more exposed to these impacts, the paint is added with an elasticizing additive to increase the elasticity of the film.\n\n

Remedy:<\/strong><\/p>\nThe entire affected area is sanded down to the product that did not jump off the support and the appropriate painting system is restored.\n\n<\/div>\n<\/div>\n

\n

Traces of water<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nTraces of water appear as small circular whitish spots, resulting from the evaporation of water in combination with mineral salts on the paint film. The surface inside the stain is almost intact, while the outer edge of the stain is slightly raised.\n\n

Cause:<\/strong><\/p>\nInsufficient drying of the paint before leaving the car in the rain.\nThe hardener used was inadequate or used in insufficient quantity.\n\n

How to avoid:<\/strong><\/p>\nMake sure that the paint is applied to the required thickness (no more) with the recommended amount of hardener so that it can dry properly.\n\n

Remedy:<\/strong><\/p>\nIf the damage is minor, wash with clean water. If it is not repaired, polish the damaged surface.\nIf the defect is large, you must sand the respective area (make sure it is well dry) and repaint.\n

The solvent test<\/h3>\nBefore starting any operation on a surface with old paint, we recommend carrying out a SOLVENT TEST, to check if the existing paint system contains solvent-sensitive paints, and for this reason the need for an appropriate treatment.\n\n

Solvent-sensitive paints:<\/strong><\/p>\nThermoplastic Acrylics (TPA);\nNitro cellulose;\nTotally unreinforced synthetics;\nPaints with the defect of slow evaporation of the solvents in the component.\n\n

How to take the test:<\/strong><\/p>\nA small portion of the piece to be repaired is sanded, so as to identify all the layers of the system.\nSoak a cloth in a strong solvent (thinner D 20), and insist on the sanded surface. It is carefully analyzed and if it is observed that a layer softens, rises or becomes sticky, then that layer is sensitive to the solvent.\n\n

Instructions for treating a surface with solvent-sensitive paint:<\/strong><\/p>\nThe sanding operation must be done with a much finer abrasive than usual and on a much larger surface.\nDo not apply putty on the sanded edges of the sensitive system; always leave clean metal between the putty and the old paint.\nApply the filler and the final paint in thin layers, leaving long airing times between layers.\nDo not apply fillers or paints in a wet-on-wet system.\nWhere the solvent-sensitive system is thick and extremely solvent-reactive, it must be completely removed to a clean sheet before starting the repair operation.\n\n<\/div>\n<\/div>\n

\n

Rust<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nDamage to the state of the paint in the form of irregular bumps. If the swollen paint is removed, rust on metal or white rust on aluminum can be seen underneath.\n\n

Cause:<\/strong><\/p>\nMechanical damage to the paint film that caused the penetration of moisture under the paint film, causing the appearance of rust on the metal substrate.\nPoor preparation and cleaning of the metal substrate before painting.\nFreshly appeared rust on freshly sandblasted surfaces.\n\n

How to avoid:<\/strong><\/p>\nScratches or stone hits must be repaired immediately.\nEnsure adequate cleaning of the metal surface before painting (degreaser).\nSandblasted surfaces must be primed immediately after sandblasting.\n\n

Remedy:<\/strong><\/p>\nRemove all the paint from the affected portion and the rust underneath, by sanding, sandblasting, etc. Clean the surface of any traces of rust, grease, etc. with a degreaser. Apply a layer of reactive primer as quickly as possible on the clean metal surface to avoid the appearance of rust and then start applying the following products (filler, paint, varnish).\n\n<\/div>\n<\/div>\n

\n

Clouds, shadows<\/h3>\n
\n\n

Definition:<\/strong><\/p>\nSpots, light or dark marks that can be observed in the metallic paint.\n\n

Cause:<\/strong><\/p>\nUneven application.\nAiring times between layers or before varnish application are too short.\nMetallic base paint applied either too full or too fizzy.\n\n

How to avoid:<\/strong><\/p>\nThe application must be uniform and overlap the pattern of the gun as best as possible.\nRespect the aeration times between layers.\nObserve the recommended layer thickness.\n\n

Remedy:<\/strong><\/p>\nIf the clouds appear during the application of the metallic base, they will be remedied by the painting technique (even and careful application).\nIf clouds, spots become visible after applying the varnish, then the varnish must be dried, sanded and the metallic paint correctly reapplied.\n\n<\/div>\n<\/div>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"Gathering Definition: Lifting or swelling (creasing) of the freshly applied layer. CAUSE: Too long drying time when working with wet-on-wet products. Repainting some solvent-sensitive paints (TPA-acrylic thermoplastics) with non-indicated products. Paints applied as insulators are applied in too thin layers or are sanded too deeply. How to avoid: Always respect the recommended cooling times (don’t […]","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"tags":[],"class_list":["post-7269","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/policolor.ro\/en\/wp-json\/wp\/v2\/pages\/7269","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/policolor.ro\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/policolor.ro\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/policolor.ro\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/policolor.ro\/en\/wp-json\/wp\/v2\/comments?post=7269"}],"version-history":[{"count":0,"href":"https:\/\/policolor.ro\/en\/wp-json\/wp\/v2\/pages\/7269\/revisions"}],"wp:attachment":[{"href":"https:\/\/policolor.ro\/en\/wp-json\/wp\/v2\/media?parent=7269"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/policolor.ro\/en\/wp-json\/wp\/v2\/tags?post=7269"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}