Identifying and eliminating paint defects.

 
Identifying and eliminating paint defects.
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                                                                                                                                       Identifying and eliminating
                                                                                                                                       paint defects.

                                                                                               44070578 GB 1005 2000 www.standox.com

                                       Standox GmbH · Postfach · D-42271 Wuppertal · Germany
Identifying and eliminating paint defects.
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     13 Water spotting

                Cause                                      Prevention                                 Remedy
                • Vehicles washed with water from ”hard”   • Never wash vehicles with household       • Wash vehicle with wax containing
                  water supply                               detergent                                  shampoo
                • Visible on dark colors, particulary on   • Rinse vehicle with chemically softened   • Dry with damp leather cloth
                  vehicles washed in direct sunlight         water                                    • Severe stains may need polishing
                                                           • Dry vehicle directly after washing         to remove
Identifying and eliminating paint defects.
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                                                                           Foreword

                                                                                     Paint defects – inevitable but manageable.
                                                                                         Paint defects can have many causes. Maybe your customer had an accident,

                                                                                         or maybe the car was exposed to aggressive atmospheric conditions. It is also possible,

                                                                                         that mistakes were made during the coating process – maybe the coat thickness was

                                                                                         not right or drying times were too short. Sometimes such damage is due to badly

                                                                                         prepared substrates. And last but not least, the conditions prevailing in the workshop

                                                                                         also play an important role.

                                                                                         In fact, it is not always easy to realise the cause at first sight. To repair a paint defect

                                                                                         effectively, however, a thorough analysis is indispensable. This brochure is designed

                                                                                         to assist you in the reliable assessment of paint defects. The different paint defects and

                                                                                         their causes are illustrated along with tips and recommendations for their professional

                                                                                         removal. To make the identification of flaws and defects easier, this brochure consists

                                                                                         of two parts. The first relates to the potential sources of defects during the preparation

                                                                                         and finishing processes, while the second takes a look at the impact our environment

                                                                                         may have on the quality and looks of a car’s paintwork.

                                                                                         You will thus be able to clearly identify the cause of a defect and eliminate it quickly –

                                                                                         i.e. before your customer complains. This will not only save you a lot of trouble,

                                                                                         time and money but also enhance your reputation as a professional refinisher delivering

                                                                                         high quality results.
Identifying and eliminating paint defects.
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                                                                           Contents

                                                                                     Refinish
                                                                                         Paint defects in alphabetical order

                                                                                         >     Adhesion problems between base and clear coats   #   12
                                                                                         >     Clouding                                         #   3
                                                                                         >     Dirt and dust in basecoat                        #   10
                                                                                         >     Dirt and dust in clearcoat                       #   11
                                                                                         >     Edge mapping                                     #   7
                                                                                         >     Lifting & wrinkling                              #   16
                                                                                         >     Matting/gloss                                    #   18
                                                                                         >     Moisture blisters                                #   14
                                                                                         >     Orange peel                                      #   6
                                                                                         >     Pinholes in polyester                            #   17
                                                                                         >     Polyester bleeding                               #   8
                                                                                         >     Poor adhesion – polyester stopper                #   15
                                                                                         >     Poor adhesion on plastic parts                   #   19
                                                                                         >     Poor opacity                                     #   13
                                                                                         >     Runs                                             #   1
                                                                                         >     Salt & pepper effect                             #   5
                                                                                         >     Sanding scratches                                #   9
                                                                                         >     Silver halo effect                               #   20
                                                                                         >     Solvent popping                                  #   4
                                                                                         >     Water spotting                                   #   2

                                                                                     Environmental
                                                                                         Paint defects in alphabetical order

                                                                                         >     Acid rain                                        #   2
                                                                                         >     Bird droppings                                   #   1
                                                                                         >     Car wash abrasions                               #   11
                                                                                         >     Color fade / change                              #   12
                                                                                         >     Corrosion                                        #   10
                                                                                         >     Industrial fall out/rail dust                    #   8
                                                                                         >     Insect secretion                                 #   6
                                                                                         >     Lime or cement dust                              #   9
                                                                                         >     Stone chip metallic                              #   4
                                                                                         >     Stone chip solid                                 #   3
                                                                                         >     Tar spots                                        #   7
                                                                                         >     Tree resin / sap                                 #   5
                                                                                         >     Water spotting                                   #   13
Identifying and eliminating paint defects.
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                                                                           Contents

                                                                                     Refinish
                                                                                         Paint defects in alphabetical order

                                                                                         >     Adhesion problems between base and clear coats   #   12
                                                                                         >     Clouding                                         #   3
                                                                                         >     Dirt and dust in basecoat                        #   10
                                                                                         >     Dirt and dust in clearcoat                       #   11
                                                                                         >     Edge mapping                                     #   7
                                                                                         >     Lifting & wrinkling                              #   16
                                                                                         >     Matting/gloss                                    #   18
                                                                                         >     Moisture blisters                                #   14
                                                                                         >     Orange peel                                      #   6
                                                                                         >     Pinholes in polyester                            #   17
                                                                                         >     Polyester bleeding                               #   8
                                                                                         >     Poor adhesion – polyester stopper                #   15
                                                                                         >     Poor adhesion on plastic parts                   #   19
                                                                                         >     Poor opacity                                     #   13
                                                                                         >     Runs                                             #   1
                                                                                         >     Salt & pepper effect                             #   5
                                                                                         >     Sanding scratches                                #   9
                                                                                         >     Silver halo effect                               #   20
                                                                                         >     Solvent popping                                  #   4
                                                                                         >     Water spotting                                   #   2

                                                                                     Environmental
                                                                                         Paint defects in alphabetical order

                                                                                         >     Acid rain                                        #   2
                                                                                         >     Bird droppings                                   #   1
                                                                                         >     Car wash abrasions                               #   11
                                                                                         >     Color fade / change                              #   12
                                                                                         >     Corrosion                                        #   10
                                                                                         >     Industrial fall out/rail dust                    #   8
                                                                                         >     Insect secretion                                 #   6
                                                                                         >     Lime or cement dust                              #   9
                                                                                         >     Stone chip metallic                              #   4
                                                                                         >     Stone chip solid                                 #   3
                                                                                         >     Tar spots                                        #   7
                                                                                         >     Tree resin / sap                                 #   5
                                                                                         >     Water spotting                                   #   13
Identifying and eliminating paint defects.
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       1        Runs                                                                                                                         Clouding                                                                                                                              3

                Cause                                      Prevention                               Remedy                                   Cause                                          Prevention                               Remedy
                • Incorrect spraying viscosity, spraying   • Follow application recommendations     • Sand and polish                        • Incorrect spraying viscosity,                •   Adjust material correctly            • When using conventional basecoat:
                  technique, flash-off times between         on technical data sheets               • Sand and repaint                         spraying technique, flash-off times,         •   Keep spray gun parallel to object      use droplet method before spraying
                  coats, and film thicknesses              • Ensure that the spray gun is in good                                              spraybooth temperature                       •   Choose suitable spray gun set up       clear
                • Defective spray gun set up                 working order                                                                   • Defective spray gun set up,                  •   Use manufacturer’s thinners          • After clear has through-dried,
                • Incorrect spraying pressure              • Warm object and material up to                                                    incorrect spraying pressure                  •   Ensure sufficient flash-off            sand surface and repaint
                • Temperature of paint, substrate or         room temperature of 20 °C/68 °F                                                 • Unsuitable thinners                          •   Follow application recommendations   • When using waterborne basecoat:
                  spraybooth too low                       • Use correct combination of hardeners                                                                                               in technical data sheets               apply uniform finish on wet basecoat
                • Incorrect choice of hardeners and          and thinners                                                                                                                                                              in accordance with technical data
                  thinners                                                                                                                                                                                                             sheet

       2        Water spotting                                                                                                               Solvent popping                                                                                                                       4

                Cause                                      Prevention                               Remedy                                   Cause                                          Prevention                               Remedy
                • Topcoat not sufficiently cured           • Follow application recommendations     • After through-drying, remove           • Insufficient drying of primer filler in      • Apply normal film thicknesses          • After drying, repaint without sanding
                • Excessive film thickness, drying time      on technical data sheets                 marks by polishing                       corners, edges, rebates and below            • Check oven temperature regularly         (within 24 hrs) or sand with Scotch brite
                  too short                                                                         • Thoroughly dry topcoat, sand             decorative strips                            • Follow recommendations on technical      ultrafine
                • Use of unsuitable thinner                                                           and repaint                            • Solvent or air trapped in film, which          data sheets                            • After drying and sanding, fill pinnholes
                • Incorrect hardener mixing ratio                                                                                              then escapes leaving pop marks due                                                      with Polyester Spray Filler or remove
                • Wrong hardener used                                                                                                          to incorrect spraying viscosity, spraying                                               damaged finish and repaint
                                                                                                                                               pressure, flash-off times and drying                                                  • Sand, prime and repaint
                                                                                                                                               times
                                                                                                                                             • Incorrect choice of hardeners and thinners
                                                                                                                                             • Film build too high
                                                                                                                                             • Wrong spraying technique
Identifying and eliminating paint defects.
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       1        Runs                                                                                                                         Clouding                                                                                                                              3

                Cause                                      Prevention                               Remedy                                   Cause                                          Prevention                               Remedy
                • Incorrect spraying viscosity, spraying   • Follow application recommendations     • Sand and polish                        • Incorrect spraying viscosity,                •   Adjust material correctly            • When using conventional basecoat:
                  technique, flash-off times between         on technical data sheets               • Sand and repaint                         spraying technique, flash-off times,         •   Keep spray gun parallel to object      use droplet method before spraying
                  coats, and film thicknesses              • Ensure that the spray gun is in good                                              spraybooth temperature                       •   Choose suitable spray gun set up       clear
                • Defective spray gun set up                 working order                                                                   • Defective spray gun set up,                  •   Use manufacturer’s thinners          • After clear has through-dried,
                • Incorrect spraying pressure              • Warm object and material up to                                                    incorrect spraying pressure                  •   Ensure sufficient flash-off            sand surface and repaint
                • Temperature of paint, substrate or         room temperature of 20 °C/68 °F                                                 • Unsuitable thinners                          •   Follow application recommendations   • When using waterborne basecoat:
                  spraybooth too low                       • Use correct combination of hardeners                                                                                               in technical data sheets               apply uniform finish on wet basecoat
                • Incorrect choice of hardeners and          and thinners                                                                                                                                                              in accordance with technical data
                  thinners                                                                                                                                                                                                             sheet

       2        Water spotting                                                                                                               Solvent popping                                                                                                                       4

                Cause                                      Prevention                               Remedy                                   Cause                                          Prevention                               Remedy
                • Topcoat not sufficiently cured           • Follow application recommendations     • After through-drying, remove           • Insufficient drying of primer filler in      • Apply normal film thicknesses          • After drying, repaint without sanding
                • Excessive film thickness, drying time      on technical data sheets                 marks by polishing                       corners, edges, rebates and below            • Check oven temperature regularly         (within 24 hrs) or sand with Scotch brite
                  too short                                                                         • Thoroughly dry topcoat, sand             decorative strips                            • Follow recommendations on technical      ultrafine
                • Use of unsuitable thinner                                                           and repaint                            • Solvent or air trapped in film, which          data sheets                            • After drying and sanding, fill pinnholes
                • Incorrect hardener mixing ratio                                                                                              then escapes leaving pop marks due                                                      with Polyester Spray Filler or remove
                • Wrong hardener used                                                                                                          to incorrect spraying viscosity, spraying                                               damaged finish and repaint
                                                                                                                                               pressure, flash-off times and drying                                                  • Sand, prime and repaint
                                                                                                                                               times
                                                                                                                                             • Incorrect choice of hardeners and thinners
                                                                                                                                             • Film build too high
                                                                                                                                             • Wrong spraying technique
Identifying and eliminating paint defects.
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       5        Salt & pepper effect                                                                                                                      Edge mapping due to solvent penetration                                                                                                7

                Cause                                     Prevention                                   Remedy                                             Cause                                      Prevention                                   Remedy
                • When using waterborne basecoats:        • Use correct mixing ratio, spray pressure   • Normally only visible after clearcoat.           • Area where topcoat was sanded            • Solvent test to identify soft substrates   • Dry topcoat thoroughly
                  over wetting of metallic basecoat         and technique for basecoat application       Therefore sanding and refinishing                  through to substrate not isolated        • Isolate using an EP filler or 2K filler;   • Sand damaged area, isolate
                  produces very small black specks in                                                    of basecoat and clearcoat stages are             • Isolated with unsuitable filler/primer     apply filler in several thin spray coats     and repaint
                  light basecoat colors                                                                  necessary                                        • Filler/primer incorrectly applied          and observe flash-off times
                                                                                                                                                          • Insufficient drying of substrate         • Avoid sanding through to soft
                                                                                                                                                                                                       substrate

       6        Orange peel                                                                                                                               Bleeding of peroxide hardener in Polyester Body Filler                                                                                 8

                Cause                                     Prevention                                   Remedy                                             Cause                                      Prevention                                   Remedy
                • Incorrect spraying pressure or          • Follow application recommendations         • Sand and repaint                                 • Use of too much hardener                 • Use of dispensing machine                  • Sand, isolate with Polyester Spray Filler,
                  viscosity, spraying technique or          from technical data sheets                 • Sand and polish                                  • Insufficient mixing                      • Check quantity of added hardener,            prime and repaint
                  application temperature                 • Prepare and sand substrate correctly                                                          • Polyester not isolated                     mix by weight
                • Unsuitable combination of solvents      • Use recommended gun set up                                                                                                               • Use recommended amount of
                  or low quality solvents                 • Always use recommended thinners                                                                                                            hardener
                • Insufficient sanding of substrate       • Avoid application at very high                                                                                                           • Mix thoroughly
                • Incorrect spray gun set up                temperatures
                • Excessive temperature
Identifying and eliminating paint defects.
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       5        Salt & pepper effect                                                                                                                      Edge mapping due to solvent penetration                                                                                                7

                Cause                                     Prevention                                   Remedy                                             Cause                                      Prevention                                   Remedy
                • When using waterborne basecoats:        • Use correct mixing ratio, spray pressure   • Normally only visible after clearcoat.           • Area where topcoat was sanded            • Solvent test to identify soft substrates   • Dry topcoat thoroughly
                  over wetting of metallic basecoat         and technique for basecoat application       Therefore sanding and refinishing                  through to substrate not isolated        • Isolate using an EP filler or 2K filler;   • Sand damaged area, isolate
                  produces very small black specks in                                                    of basecoat and clearcoat stages are             • Isolated with unsuitable filler/primer     apply filler in several thin spray coats     and repaint
                  light basecoat colors                                                                  necessary                                        • Filler/primer incorrectly applied          and observe flash-off times
                                                                                                                                                          • Insufficient drying of substrate         • Avoid sanding through to soft
                                                                                                                                                                                                       substrate

       6        Orange peel                                                                                                                               Bleeding of peroxide hardener in Polyester Body Filler                                                                                 8

                Cause                                     Prevention                                   Remedy                                             Cause                                      Prevention                                   Remedy
                • Incorrect spraying pressure or          • Follow application recommendations         • Sand and repaint                                 • Use of too much hardener                 • Use of dispensing machine                  • Sand, isolate with Polyester Spray Filler,
                  viscosity, spraying technique or          from technical data sheets                 • Sand and polish                                  • Insufficient mixing                      • Check quantity of added hardener,            prime and repaint
                  application temperature                 • Prepare and sand substrate correctly                                                          • Polyester not isolated                     mix by weight
                • Unsuitable combination of solvents      • Use recommended gun set up                                                                                                               • Use recommended amount of
                  or low quality solvents                 • Always use recommended thinners                                                                                                            hardener
                • Insufficient sanding of substrate       • Avoid application at very high                                                                                                           • Mix thoroughly
                • Incorrect spray gun set up                temperatures
                • Excessive temperature
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       9        Sanding scratches                                                                                                                               Dirt and dust in clearcoat                                                                                                               11

                Cause                                       Prevention                                      Remedy                                              Cause                                         Prevention                                      Remedy
                •   Sanding paper too coarse                • Use recommended grade sanding                 • Thoroughly dry and sand                           • During application, dirt is attracted       • Ensure the spraybooth is clean at all times   • Sanding and polishing will only remove
                •   Filler sanded when soft                   paper                                         • Isolate or remove substrate, repaint                to the clearcoat and is trapped in the      • Blow out crevices to ensure all dust is         dirt on the surface of the clearcoat
                •   Insufficient sanded polyester stopper   • Isolate repaired areas with 2K filler                                                               wet film                                      removed at every stage of preparation         • Otherwise refinishing of the basecoat
                •   Insufficient isolation of the stopper   • Dry filler thoroughly                                                                             • Is seen as dark or light specks depending   • Wear lint free spraysuit                        and clearcoat is required
                    before topcoat application                                                                                                                    on the color of the surface

      10 Dirt and dust in basecoat                                                                                                                              Adhesion problems between base and clear coats                                                                                           12

                Cause                                       Prevention                                      Remedy                                              Cause                                         Prevention                                      Remedy
                • Dirt entering wet film either from air-   • Ensure the spraybooth is clean at all times   • Denib dirt particles and re-apply base-           • Excessive coat thickness of basecoat        • Apply basecoat film thickness according       • Sand and repaint
                  borne contamination or from unfiltered    • Blow out crevices to ensure all dust            coat to affected areas as required                • Intermediate and final flash-off times        to technical data sheet
                  basecoat                                    is removed at every stage of preparation                                                            of the basecoat too short                   • Use the intermediate and final flash off
                                                            • Wear lint free spraysuit                                                                          • Wrong mixing ratio of clearcoat/              times from the technical data sheet
                                                            • Use paint strainer/filter                                                                           hardener                                    • Choose and mix clearcoat, hardener
                                                                                                                                                                • Incorrect hardener/thinner combination;       and thinner according to technical
                                                                                                                                                                  system too fast                               data sheets
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       9        Sanding scratches                                                                                                                               Dirt and dust in clearcoat                                                                                                               11

                Cause                                       Prevention                                      Remedy                                              Cause                                         Prevention                                      Remedy
                •   Sanding paper too coarse                • Use recommended grade sanding                 • Thoroughly dry and sand                           • During application, dirt is attracted       • Ensure the spraybooth is clean at all times   • Sanding and polishing will only remove
                •   Filler sanded when soft                   paper                                         • Isolate or remove substrate, repaint                to the clearcoat and is trapped in the      • Blow out crevices to ensure all dust is         dirt on the surface of the clearcoat
                •   Insufficient sanded polyester stopper   • Isolate repaired areas with 2K filler                                                               wet film                                      removed at every stage of preparation         • Otherwise refinishing of the basecoat
                •   Insufficient isolation of the stopper   • Dry filler thoroughly                                                                             • Is seen as dark or light specks depending   • Wear lint free spraysuit                        and clearcoat is required
                    before topcoat application                                                                                                                    on the color of the surface

      10 Dirt and dust in basecoat                                                                                                                              Adhesion problems between base and clear coats                                                                                           12

                Cause                                       Prevention                                      Remedy                                              Cause                                         Prevention                                      Remedy
                • Dirt entering wet film either from air-   • Ensure the spraybooth is clean at all times   • Denib dirt particles and re-apply base-           • Excessive coat thickness of basecoat        • Apply basecoat film thickness according       • Sand and repaint
                  borne contamination or from unfiltered    • Blow out crevices to ensure all dust            coat to affected areas as required                • Intermediate and final flash-off times        to technical data sheet
                  basecoat                                    is removed at every stage of preparation                                                            of the basecoat too short                   • Use the intermediate and final flash off
                                                            • Wear lint free spraysuit                                                                          • Wrong mixing ratio of clearcoat/              times from the technical data sheet
                                                            • Use paint strainer/filter                                                                           hardener                                    • Choose and mix clearcoat, hardener
                                                                                                                                                                • Incorrect hardener/thinner combination;       and thinner according to technical
                                                                                                                                                                  system too fast                               data sheets
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      13 Poor opacity                                                                                                                           Poor adhesion – polyester stopper                                                                                               15

                Cause                                       Prevention                               Remedy                                     Cause                                    Prevention                                 Remedy
                • Substrate not uniform (Effect finishes)   • Spray a uniform substrate              • Sand and repaint                         • Poor substrate preparation             • Clean and sand thoroughly                • Sand the damaged repair area well
                • Topcoat film build too low                • Spray sufficient topcoat to obtain                                                • Polyester material unsuitable for      • Only use Standox Stopper                   to remove all polyester stopper
                • Coating overthinned                         opacity                                                                             galvanized substrate                     recommended for galvanized               • Only use Standox Stopper
                                                            • Avoid excessive amounts of thinner                                                • Surface temperature too high while       substrates                                 recommended for galvanized
                                                                                                                                                  forced drying                          • Follow the manufacturer’s instructions     substrates
                                                                                                                                                • Undercured – too much /too little        for forced drying                        • Repair and repaint
                                                                                                                                                  hardener                               • Keep to the mixing ratio
                                                                                                                                                                                         • Ensure hardener is completely mixed
                                                                                                                                                                                           into the polyester stopper

      14 Moisture blisters                                                                                                                      Lifting & wrinkling                                                                                                             16

                Cause                                       Prevention                               Remedy                                     Cause                                    Prevention                                 Remedy
                • Residue of sanding water in corners,      • Always remove exterior trim            • Remove all contaminated finish           • Occurs when chemical reaction          • Avoid working on high film thicknesses   • Remove all coating and refinish from
                  edges, rebates and below decorative       • Blow and dry carefully with air          and repaint                                takes place between two incompatible   • Ensure all products used are part of a     metal stage
                  strips                                    • Check air supply equipment regularly                                                substrates                               refinish system                          • Alternative remedies are not guarenteed
                • Contaminated air supply                   • Ensure correct flash off/curing of                                                • High film builds                       • Allow materials to flash off and dry       and can be unstable
                • Insufficient isolation of polyesters        waterborne products                                                               • Overcoating an uncured substrate         in accordance to technical data sheets
                • Air humidity too high                     • Before processing and spraying,                                                   • Wet-on-wet system combined with        • Use recommended hardener/thinner
                • Waterborne products not completely          clean according to instructions                                                     incorrect hardener/thinner               combination
                  flashed off/cured
                • Dried salt residues
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      13 Poor opacity                                                                                                                           Poor adhesion – polyester stopper                                                                                               15

                Cause                                       Prevention                               Remedy                                     Cause                                    Prevention                                 Remedy
                • Substrate not uniform (Effect finishes)   • Spray a uniform substrate              • Sand and repaint                         • Poor substrate preparation             • Clean and sand thoroughly                • Sand the damaged repair area well
                • Topcoat film build too low                • Spray sufficient topcoat to obtain                                                • Polyester material unsuitable for      • Only use Standox Stopper                   to remove all polyester stopper
                • Coating overthinned                         opacity                                                                             galvanized substrate                     recommended for galvanized               • Only use Standox Stopper
                                                            • Avoid excessive amounts of thinner                                                • Surface temperature too high while       substrates                                 recommended for galvanized
                                                                                                                                                  forced drying                          • Follow the manufacturer’s instructions     substrates
                                                                                                                                                • Undercured – too much /too little        for forced drying                        • Repair and repaint
                                                                                                                                                  hardener                               • Keep to the mixing ratio
                                                                                                                                                                                         • Ensure hardener is completely mixed
                                                                                                                                                                                           into the polyester stopper

      14 Moisture blisters                                                                                                                      Lifting & wrinkling                                                                                                             16

                Cause                                       Prevention                               Remedy                                     Cause                                    Prevention                                 Remedy
                • Residue of sanding water in corners,      • Always remove exterior trim            • Remove all contaminated finish           • Occurs when chemical reaction          • Avoid working on high film thicknesses   • Remove all coating and refinish from
                  edges, rebates and below decorative       • Blow and dry carefully with air          and repaint                                takes place between two incompatible   • Ensure all products used are part of a     metal stage
                  strips                                    • Check air supply equipment regularly                                                substrates                               refinish system                          • Alternative remedies are not guarenteed
                • Contaminated air supply                   • Ensure correct flash off/curing of                                                • High film builds                       • Allow materials to flash off and dry       and can be unstable
                • Insufficient isolation of polyesters        waterborne products                                                               • Overcoating an uncured substrate         in accordance to technical data sheets
                • Air humidity too high                     • Before processing and spraying,                                                   • Wet-on-wet system combined with        • Use recommended hardener/thinner
                • Waterborne products not completely          clean according to instructions                                                     incorrect hardener/thinner               combination
                  flashed off/cured
                • Dried salt residues
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      17 Pinholes in polyester                                                                                                                   Poor adhesion on plastic parts                                                                                                   19

                Cause                                       Prevention                               Remedy                                      Cause                                       Prevention                                Remedy
                • Substrate insufficiently dried            • Allow preparation materials to dry     • Fill pinholes with spray filler           • Insufficient cleaning, drying             • Temper parts before cleaning and        • Steam clean, sand, reclean and
                • Polyester material not isolated with        thoroughly                             • Sand damaged area and repaint               (tempering)                                 priming                                   repaint
                  2K filler                                 • Deeply sand pores or re-apply                                                      • Incorrect primer has been used            • Clean and degrease properly             • Remove damaged finish and repaint
                • Pores not deeply sanded                     filler/stopper                                                                     • Incorrect paint system                    • Ensure solvents have evaporated
                                                            • Use a fine stopper to finish repair                                                                                            • Use a suitable adhesion primer
                                                            • Mix hardener and stopper as                                                                                                    • Work in accordance with data sheet
                                                              completely as possible; avoid
                                                              air bubbles
                                                            • Stopper application at a right angle
                                                              prevents the formations of pores

      18 Matting/gloss                                                                                                                           Silver halo effect                                                                                                               20

                Cause                                       Prevention                               Remedy                                      Cause                                       Prevention                                Remedy
                • Film thickness or air humidity too high   • Follow application recommendations     • Sand and polish                           • Typically caused by incorrect technique   • Observe recommendations on blend        • Respray affected area with correct
                • Substrate too sensitive to solvents         on technical data sheets               • Sand and repaint                            when blending in metallics                  in techique                               technique, may be possible at basecoat
                • Incorrect mixing or contaminated          • Close hardener cans firmly after use                                               • Can also be visible as dark edge on       • Ensure correct mixing ratio and spray     stage before clearcoat
                  hardener                                  • Ensure sufficient airflow in oven                                                    light colors                                pressure for metallic basecoat
                • Use of unsuitable thinner                   during drying cycle
                • Insufficient airflow in oven              • Don’t interrupt baking cycle
                • Interrupted baking
                • Clearcoat applied too fast
                • Incorrect polish applied too soon
                  after drying
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      17 Pinholes in polyester                                                                                                                   Poor adhesion on plastic parts                                                                                                   19

                Cause                                       Prevention                               Remedy                                      Cause                                       Prevention                                Remedy
                • Substrate insufficiently dried            • Allow preparation materials to dry     • Fill pinholes with spray filler           • Insufficient cleaning, drying             • Temper parts before cleaning and        • Steam clean, sand, reclean and
                • Polyester material not isolated with        thoroughly                             • Sand damaged area and repaint               (tempering)                                 priming                                   repaint
                  2K filler                                 • Deeply sand pores or re-apply                                                      • Incorrect primer has been used            • Clean and degrease properly             • Remove damaged finish and repaint
                • Pores not deeply sanded                     filler/stopper                                                                     • Incorrect paint system                    • Ensure solvents have evaporated
                                                            • Use a fine stopper to finish repair                                                                                            • Use a suitable adhesion primer
                                                            • Mix hardener and stopper as                                                                                                    • Work in accordance with data sheet
                                                              completely as possible; avoid
                                                              air bubbles
                                                            • Stopper application at a right angle
                                                              prevents the formations of pores

      18 Matting/gloss                                                                                                                           Silver halo effect                                                                                                               20

                Cause                                       Prevention                               Remedy                                      Cause                                       Prevention                                Remedy
                • Film thickness or air humidity too high   • Follow application recommendations     • Sand and polish                           • Typically caused by incorrect technique   • Observe recommendations on blend        • Respray affected area with correct
                • Substrate too sensitive to solvents         on technical data sheets               • Sand and repaint                            when blending in metallics                  in techique                               technique, may be possible at basecoat
                • Incorrect mixing or contaminated          • Close hardener cans firmly after use                                               • Can also be visible as dark edge on       • Ensure correct mixing ratio and spray     stage before clearcoat
                  hardener                                  • Ensure sufficient airflow in oven                                                    light colors                                pressure for metallic basecoat
                • Use of unsuitable thinner                   during drying cycle
                • Insufficient airflow in oven              • Don’t interrupt baking cycle
                • Interrupted baking
                • Clearcoat applied too fast
                • Incorrect polish applied too soon
                  after drying
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       1        Bird droppings                                                                                                                             Stone chip solid                                                                                                             3

                Cause                                         Prevention                               Remedy                                              Cause                                      Prevention                                  Remedy
                • Acids present in bird droppings can         • Remove droppings as soon as possible   • Cover with wet paper towel and leave              • The result of stones thrown up by        • Plastic film to cover susceptible areas   • Minor damages can be repaired
                  penetrate the paint film and cause          • Protect finish with high quality wax     for a few minutes                                   vehicle tyres hitting the paint film       on vehicle                                  by careful touching
                  varying problems ranging from mild            polish (frequently)                    • Remove paper and wipe away dropping,              • Can lead to corrosion in extreme         • Fitting of mud flaps can reduce damages   • Micro /Spot repair or complete
                  staining to penetration through to          • Avoid parking under trees                and allow to dry                                    cases                                      to lower areas                              refinishing is necessary for true
                  the Zinc layer                                                                       • Stanining can be removed by polishing                                                        • Use paint systems recommended by            rectification
                                                                                                         local area, or refinishing if damage is                                                        vehicle manufacturer (see approval
                                                                                                         more severe                                                                                    systems)

       2        Acid rain                                                                                                                                  Stone chip metallic                                                                                                          4

                Cause                                         Prevention                               Remedy                                              Cause                                      Prevention                                  Remedy
                • Chemicals released into atmosphere          • Avoid parking in industrial areas      • Polishing may remove mild damage                  • The result of stones thrown up by        • Plastic film to cover susceptible areas   • Very small areas can be repaired
                  reacting with hydrocarbons in the air       • Protect finish by frequent washing     • Refinish areas where film is broken                 vehicle tyres hitting the paint film       on vehicle                                  by careful touching in, although
                • Visible as rain drops on surface in areas     and waxing to provide resistance       • Light marks can be removed with a                 • Can lead to corrosion in extreme cases   • Fitting of mud flaps can reduce damage      must be protected by clearcoat
                  where mixture is strong                                                                cleaning clay                                                                                  to lower areas                            • Micro / Spot repair or complete
                • Can cause unrepairable damage                                                                                                                                                       • Use paint systems recommended by            refinishing is necessary for true
                                                                                                                                                                                                        vehicle manufacturer (see approval          rectification
                                                                                                                                                                                                        systems)
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       1        Bird droppings                                                                                                                             Stone chip solid                                                                                                             3

                Cause                                         Prevention                               Remedy                                              Cause                                      Prevention                                  Remedy
                • Acids present in bird droppings can         • Remove droppings as soon as possible   • Cover with wet paper towel and leave              • The result of stones thrown up by        • Plastic film to cover susceptible areas   • Minor damages can be repaired
                  penetrate the paint film and cause          • Protect finish with high quality wax     for a few minutes                                   vehicle tyres hitting the paint film       on vehicle                                  by careful touching
                  varying problems ranging from mild            polish (frequently)                    • Remove paper and wipe away dropping,              • Can lead to corrosion in extreme         • Fitting of mud flaps can reduce damages   • Micro /Spot repair or complete
                  staining to penetration through to          • Avoid parking under trees                and allow to dry                                    cases                                      to lower areas                              refinishing is necessary for true
                  the Zinc layer                                                                       • Stanining can be removed by polishing                                                        • Use paint systems recommended by            rectification
                                                                                                         local area, or refinishing if damage is                                                        vehicle manufacturer (see approval
                                                                                                         more severe                                                                                    systems)

       2        Acid rain                                                                                                                                  Stone chip metallic                                                                                                          4

                Cause                                         Prevention                               Remedy                                              Cause                                      Prevention                                  Remedy
                • Chemicals released into atmosphere          • Avoid parking in industrial areas      • Polishing may remove mild damage                  • The result of stones thrown up by        • Plastic film to cover susceptible areas   • Very small areas can be repaired
                  reacting with hydrocarbons in the air       • Protect finish by frequent washing     • Refinish areas where film is broken                 vehicle tyres hitting the paint film       on vehicle                                  by careful touching in, although
                • Visible as rain drops on surface in areas     and waxing to provide resistance       • Light marks can be removed with a                 • Can lead to corrosion in extreme cases   • Fitting of mud flaps can reduce damage      must be protected by clearcoat
                  where mixture is strong                                                                cleaning clay                                                                                  to lower areas                            • Micro / Spot repair or complete
                • Can cause unrepairable damage                                                                                                                                                       • Use paint systems recommended by            refinishing is necessary for true
                                                                                                                                                                                                        vehicle manufacturer (see approval          rectification
                                                                                                                                                                                                        systems)
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       5        Tree rasin/sap                                                                                                                   Tar spots                                                                                                                              7

                Cause                                        Prevention                              Remedy                                      Cause                                            Prevention                               Remedy
                • Secretions of tree resin/sap interacting   • Clean off immediately with water or   • Avoid parking under trees                 • Driving over newly tarmaced road               • Avoid drving on newly surfaced roads   • Easily removed by solvent based
                  with climate and time                        mild detergent solution               • Minor defects can be removed by             surfaces                                                                                  cleaner, or with fine polishing abrasive
                                                             • Protect by frequent wax polishing       polishing                                 • Visible as small black or brown specks                                                  • Re-coat finish with wax polish after
                                                                                                     • Remove contaminated areas back                                                                                                        removal of spots
                                                                                                       to metal and refinish

       6        Insect secretion                                                                                                                 Industrial fall out/rail dust                                                                                                          8

                Cause                                        Prevention                              Remedy                                      Cause                                            Prevention                               Remedy
                • Alkaline residue of insects during         • Clean off immediately with warm       • Light defects can be removed by           • Contamination of the surface by very           • Clean off surface immediately          • Minor defects can be removed by
                  driving, in interaction with surface,        water or mild detergent solution        polishing                                   small pieces of metal                          • Frequent wax polishing to provide        polishing
                  climate and time                           • Protect by frequent wax polishing     • Otherwise sand and refinish the           • These include rail dust, industrial fall out     barrier for paint film                 • Deeper damage must be removed
                                                                                                       affected area                               or grinding sparks                                                                        and refinished
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       5        Tree rasin/sap                                                                                                                   Tar spots                                                                                                                              7

                Cause                                        Prevention                              Remedy                                      Cause                                            Prevention                               Remedy
                • Secretions of tree resin/sap interacting   • Clean off immediately with water or   • Avoid parking under trees                 • Driving over newly tarmaced road               • Avoid drving on newly surfaced roads   • Easily removed by solvent based
                  with climate and time                        mild detergent solution               • Minor defects can be removed by             surfaces                                                                                  cleaner, or with fine polishing abrasive
                                                             • Protect by frequent wax polishing       polishing                                 • Visible as small black or brown specks                                                  • Re-coat finish with wax polish after
                                                                                                     • Remove contaminated areas back                                                                                                        removal of spots
                                                                                                       to metal and refinish

       6        Insect secretion                                                                                                                 Industrial fall out/rail dust                                                                                                          8

                Cause                                        Prevention                              Remedy                                      Cause                                            Prevention                               Remedy
                • Alkaline residue of insects during         • Clean off immediately with warm       • Light defects can be removed by           • Contamination of the surface by very           • Clean off surface immediately          • Minor defects can be removed by
                  driving, in interaction with surface,        water or mild detergent solution        polishing                                   small pieces of metal                          • Frequent wax polishing to provide        polishing
                  climate and time                           • Protect by frequent wax polishing     • Otherwise sand and refinish the           • These include rail dust, industrial fall out     barrier for paint film                 • Deeper damage must be removed
                                                                                                       affected area                               or grinding sparks                                                                        and refinished
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       9        Lime or cement dust                                                                                                                          Car wash abrasions                                                                                                                  11

                Cause                                        Prevention                                     Remedy                                           Cause                                          Prevention                                  Remedy
                • Etching effect on the paint surface        • Clean off immediately with water or          • Polishing with abrasive paste may              • Damaged or dirty automatic car wash          • Avoid automatic car wash machines         • Scratches can be removed by machine
                  caused by lime or cement, in interaction     mild detergent solution, followed by           work for mild damage, otherwise sand             brushes                                      • Use scratch resistant clear in refinish     polishing with fine abrasive paste
                  with climate and time                        polishing                                      affected area and refinish                                                                      process                                   • Avoid over polishing, can be checked
                                                             • Frequent wax polishing to provide                                                                                                                                                          with film thickness gauge
                                                               barrier

     10 Corrosion                                                                                                                                            Color fade/change                                                                                                                   12

                Cause                                        Prevention                                     Remedy                                           Cause                                          Prevention                                  Remedy
                • Moisture penetration through broken        • Frequent washing and wax polishing           • Remove affected paint areas,                   • Sunlight UV light effect on certain paint    • Frequent wax polishing to provide         • Can be removed in part by machine
                  areas in paint film                          of the vehicle, particulary in winter          sandblast heavily affected areas                 pigments in surface                            protection                                  polishing with fine abrasive paste
                • Exposed bare metal areas                   • Refinish broken paint surfaces immediately   • Treat with neutralizing acid                   • Refinish paints of low quality with little                                               • Avoid over polishing, can be checked
                • Climate and time influence degree of         to prevent corrosion starting                • Refinish with approved system                    or no UV blocker                                                                           with film thickness gauge
                  corrosion damage                                                                                                                                                                                                                      • Refinish if necessary
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       9        Lime or cement dust                                                                                                                          Car wash abrasions                                                                                                                  11

                Cause                                        Prevention                                     Remedy                                           Cause                                          Prevention                                  Remedy
                • Etching effect on the paint surface        • Clean off immediately with water or          • Polishing with abrasive paste may              • Damaged or dirty automatic car wash          • Avoid automatic car wash machines         • Scratches can be removed by machine
                  caused by lime or cement, in interaction     mild detergent solution, followed by           work for mild damage, otherwise sand             brushes                                      • Use scratch resistant clear in refinish     polishing with fine abrasive paste
                  with climate and time                        polishing                                      affected area and refinish                                                                      process                                   • Avoid over polishing, can be checked
                                                             • Frequent wax polishing to provide                                                                                                                                                          with film thickness gauge
                                                               barrier

     10 Corrosion                                                                                                                                            Color fade/change                                                                                                                   12

                Cause                                        Prevention                                     Remedy                                           Cause                                          Prevention                                  Remedy
                • Moisture penetration through broken        • Frequent washing and wax polishing           • Remove affected paint areas,                   • Sunlight UV light effect on certain paint    • Frequent wax polishing to provide         • Can be removed in part by machine
                  areas in paint film                          of the vehicle, particulary in winter          sandblast heavily affected areas                 pigments in surface                            protection                                  polishing with fine abrasive paste
                • Exposed bare metal areas                   • Refinish broken paint surfaces immediately   • Treat with neutralizing acid                   • Refinish paints of low quality with little                                               • Avoid over polishing, can be checked
                • Climate and time influence degree of         to prevent corrosion starting                • Refinish with approved system                    or no UV blocker                                                                           with film thickness gauge
                  corrosion damage                                                                                                                                                                                                                      • Refinish if necessary
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     13 Water spotting

                Cause                                      Prevention                                 Remedy
                • Vehicles washed with water from ”hard”   • Never wash vehicles with household       • Wash vehicle with wax containing
                  water supply                               detergent                                  shampoo
                • Visible on dark colors, particulary on   • Rinse vehicle with chemically softened   • Dry with damp leather cloth
                  vehicles washed in direct sunlight         water                                    • Severe stains may need polishing
                                                           • Dry vehicle directly after washing         to remove
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                                                                           Foreword

                                                                                     Paint defects – inevitable but manageable.
                                                                                         Paint defects can have many causes. Maybe your customer had an accident,

                                                                                         or maybe the car was exposed to aggressive atmospheric conditions. It is also possible,

                                                                                         that mistakes were made during the coating process – maybe the coat thickness was

                                                                                         not right or drying times were too short. Sometimes such damage is due to badly

                                                                                         prepared substrates. And last but not least, the conditions prevailing in the workshop

                                                                                         also play an important role.

                                                                                         In fact, it is not always easy to realise the cause at first sight. To repair a paint defect

                                                                                         effectively, however, a thorough analysis is indispensable. This brochure is designed

                                                                                         to assist you in the reliable assessment of paint defects. The different paint defects and

                                                                                         their causes are illustrated along with tips and recommendations for their professional

                                                                                         removal. To make the identification of flaws and defects easier, this brochure consists

                                                                                         of two parts. The first relates to the potential sources of defects during the preparation

                                                                                         and finishing processes, while the second takes a look at the impact our environment

                                                                                         may have on the quality and looks of a car’s paintwork.

                                                                                         You will thus be able to clearly identify the cause of a defect and eliminate it quickly –

                                                                                         i.e. before your customer complains. This will not only save you a lot of trouble,

                                                                                         time and money but also enhance your reputation as a professional refinisher delivering

                                                                                         high quality results.
THK_Paint Defects_s0120.qxd   12.09.2005   13:02 Uhr   Seite 2

                                                                                                                                       Identifying and eliminating
                                                                                                                                       paint defects.

                                                                                               44070578 GB 1005 2000 www.standox.com

                                       Standox GmbH · Postfach · D-42271 Wuppertal · Germany
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