Identifying and eliminating paint defects.
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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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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
THK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 1
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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_InGB.fh9 04.10.2005 10:08 Uhr Seite 2
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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
THK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 2
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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
THK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 3
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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
THK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 3
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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
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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
THK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 4
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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 temperatureTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 5
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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 sheetsTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 5
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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 sheetsTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 6
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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 residuesTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 6
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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 residuesTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 7
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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 dryingTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 7
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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 dryingTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 8
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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)THK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 8
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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)THK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 9
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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 refinishedTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 9
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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 refinishedTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 10
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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 necessaryTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 10
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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 necessaryTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 11
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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 removeTHK_Paint Defects_InGB.fh9 04.10.2005 10:08 Uhr Seite 1
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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 · GermanyYou can also read
