What Causes Bleeding?

This can be caused by the presence of solvent in the new topcoat, which can dissolve soluble dyes or pigments in the original finish and seep into the topcoat as it dries. This is more common in older cars with synthetic enamel finishes.

Repair:

1. Allow colour to cure & isolate with two component undercoat(s) before refinishing.
2. Alternatively you can remove original paint film and refinish.

Prevention:

Applying a sealer or a two-component undercoat before you refinish will prevent bleeding. Once the sealer or undercoat has been applied, wait until cured before applying the top coat.

What causes chipping?

Loss of adhesion of the paint film to the substrate caused by an impact from stones or other hard objects.

Repair:

Sand and feather edge damaged areas to remove chips, and then refinish.

Prevention:

1. Use premium two component undercoat and topcoat system – chips are far more common on cars that don’t have correct undercoat and topcoat components
2. Use a flex agent in undercoat and/or topcoat system in areas that are prone to chipping.

What Causes Cracking

1. Excessive film thickness of the undercoat and/or topcoat.
2. Refinishing over a previously crazed/cracked surface.
3. Insufficient flash time between coats and/or force drying undercoats using air from the spray gun.
4. Mixing incorrectly or using too much hardener.
5. Paint ingredients not thoroughly stirred or agitated.
6. Breakdown of finish due to prolonged exposure to sunlight, moisture, and extreme temperature changes.
7. Using generic reducers and/or hardeners.

Repair:

Remove all cracked paint film and refinish.

Prevention:

1. Apply all materials following label direction.
2. Completely remove crazed/cracked finishes before refinishing.
3. Do not force dry undercoats by fanning with spray gun air.
4. Mix ingredients thoroughly using the recommended additives. Add each component in proper sequence following the recommended mixing ratio.
5. Stir or agitate materials thoroughly before use to ensure all ingredients are in solution.
6. Use premium two component undercoat and topcoat system to provide maximum gloss and durability.
7. Use the recommended thinner/reducer and hardener, and then measure accurately.

What Causes Dust Contamination?

1. Inadequate cleaning of the surface to be painted.
2. Dirty spraying environment.
3. Inadequate air filtration or unfiltered air entering the booth.
4. Dirty or unsuitable work clothes that contain dust, lint or fibres.
5. Particles from deteriorated air supply lines.
6. Using a poor grade masking paper.
7. Dirty spray gun.
8. Removing the vehicle from the spray booth before the finish is ‘dust free’.

Repair:

1. Sand with 1200 or finer grit sandpaper, then compound and polish to restore gloss.
2. Or, sand smooth and refinish.

Prevention:

1. Thoroughly blow off around windows, doors, jambs, hood, trunk, mouldings, engine compartment, and wheel openings. Wipe the surface to be painted and the masking paper with the tack rag.
2. Maintain a clean working area.
3. Install proper air filters. Repair any leakage found in the spray booth due to poor fitting doors, gaskets, seams or filters.
4. Wear a lint free paint suit during the spray application.
5. Use quality masking materials. ‘Wicks’ found on newspaper can break away and blow into the wet paint.
6. Repair or replace defective air lines.
7. Properly clean and maintain spray equipment.
8. Vehicle should be kept in a clean environment until finish is ‘dust free’.

What causes Edge Mapping?

Solvent from the new topcoat penetrates a solvent sensitive substrate causing a lifting or wrinkling that outlines the feather edge.

Repair:

1. Sand smooth or remove the affected area. Final sand with 400 or finer grit sandpaper.
2. Isolate affected area with two component primer surfacer and refinish.
3. Or, apply acrylic lacquer primer surfacer thinned with non-penetrating thinner, sand smooth and refinish.

Prevention:

Check questionable finishes by rubbing a small inconspicuous area with a shop towel saturated with lacquer thinner. Finishes susceptible to lifting will soften, wrinkle or shrivel as lacquer thinner is applied. If any of these reactions occur, the following recommendations should be considered.

1. Use acrylic urethane primer surfacer or an acrylic lacquer primer surfacer thinned with non-penetrating thinner over sensitive substrates.
2. Use 400 or finer grit sandpaper when feather edging.
3. Avoid sanding through insoluble topcoat colour or clear, exposing solvent sensitive or soluble finishes

What Causes Fisheyes?

1. Spraying over surfaces contaminated with oil, wax, silicone, grease, etc.
2. Use of thinner/reducer in place of a solvent cleaner.
3. Incorrect Cleaning Processes

Repair:

1. Remove wet paint film with solvent, clean and refinish.
2. Add the recommended fisheye eliminator and respray the affected area.
3. If fisheyes appear in a basecoat, allow the colour to flash then spray a mist coat over affected area. Do not use fisheye eliminator in undercoats or basecoat colour.
4. If the paint has dried, sand to a smooth finish below the fisheye cratering and refinish.

Prevention:

1. Thoroughly clean the surface to be painted with detergent and hot water, followed by the recommended solvent cleaner. Wipe dry with clean rags.
2. Install an air filtering system that removes and prevents oil and moisture contamination.
3. Maintain air supply by draining, cleaning and changing filter(s) on a routine basis

What causes Lifting?

Solvents in a newly applied product can eat away at the previous finish causing wrinkling, raising or puckering of the paint film due to:

1. Recoating enamels or urethanes that are not fully cured.
2. Exceeding maximum flash or recoat times during application.
3. Recoating a basecoat/clearcoat finish where the existing clearcoat has insufficient film build.

Repair:

Remove the section of paint that has lifted and refinish

Prevention:

Check questionable finishes by rubbing a small inconspicuous area with a shop towel saturated with lacquer thinner. Finishes susceptible to lifting will soften, swell or shrivel as lacquer thinner is applied. If any of these reactions occur the following recommendations should be considered.

1. Do not exceed a product’s maximum recoat time during or after application.
2. Allow enamels or urethanes to thoroughly cure before recoating or attempting a repair.
3. Avoid applying undercoats or topcoats excessively wet.
4. Avoid the use of lacquer products over an air dried enamel finish.
5. When insoluble material (enamel/urethane) has been applied over a soluble material (lacquer):
   a.  Avoid sanding through and exposing areas of the soluble material.
   b.  Apply two component primer surfacer and/or sealer as a barrier between the new and the old finish. When applying two component undercoats over soluble finishes, the complete panel must be coated.

1. Topcoat applied in heavy, wet coats.
2. Inadequate flash time between coats.
3. Insufficient film thickness of topcoat colour or clearcoat.
4. Insufficient drying/curling of undercoats before applying topcoats.
5. Using a poor grade and/or too fast evaporating thinner/reducer for spray conditions.
6. Improper cleaning of the substrate.
7. Insufficient air movement during and after application.
8. Spraying over a deteriorated or solvent sensitive substrate finish without proper priming or sealing procedures.
9. Natural weathering of the finish.

Repair:

1. Allow finish to cure thoroughly, compound or polish to restore gloss.
2. Or, sand and refinish.

Prevention:

1. Apply the topcoat according to product label directions using the recommended gun set-up and air pressure.
2. Allow all coatings sufficient flash between coats.
3. Apply sufficient number of coats to achieve recommended proper film thickness. Check with a film thickness gauge if possible.
4. Allow undercoats to thoroughly dry/cure before topcoating.
5. Select recommended thinner/reducer based on temperature, humidity, air movement, and size of repair.
6. Clean substrate thoroughly before and after sanding.
7. For air dry situations:
   1. Allow exhaust fan to run 40 minutes or longer after spraying
   2. Open booth doors after finish is dust free
   3. Maintain a shop temperature of 18° Celsius or above, especially when drying overnight.
8. For maximum holdout use a premium two component undercoat system.
9. Properly wash and care for the finish on a regular basis.
10. Using premium topcoat colour or clearcoat system will provide maximum gloss and durability

What causes Mottling?

1. An uneven distribution of metallic flake caused by:
   1. Using a spray gun that gives an unbalanced spray pattern.
   2. Improper application technique such as tilting the spray gun during application, causing the spray pattern to become heavy at the top or bottom.
   3. Holding the gun too close to the surface (flooding).
   4. Uneven spray pattern overlap.
   5. Omitting/Improper use of mist coats.
2. Too much thinner/reducer. Colour over thinned/reduced.
3. Applying clearcoat to a basecoat that has not thoroughly flashed/dried.
4. Improper application of basecoat (e.g. failure to apply or an improper use of a low pressure mist coat, wet basecoat application).

Repair:

1. To uniform single stage metallic finishes, apply a higher pressure mist coat, panel by panel, while previous coat is still wet.
2. Or, allow basecoat colour to flash, and then apply a low pressure mist coat.
3. Finishes that have dried must be sanded and refinished. Caution: Large areas of basecoat must have clearcoat applied before sanding. However, small nibs or lint may be removed from basecoat by wet sanding, concentrating only on the defect. Apply additional basecoat to the sanded area before clearcoating.

Prevention:

1. Use recommended spray gun, including fluid tip and air cap for the material being sprayed. Always adjust the gun for best atomisation and balanced spray pattern before paint application.
2. Use the correct ratio of thinner/reducer.
3. Allow basecoat proper flash/dry time before clearcoating.
4. Follow basecoat application procedures.

What Causes Orange Peel?

1. Under reduction and/or air pressure too low.
2. Thinner/reducer evaporates too fast for spray conditions.
3. Excessive film thickness or piling on of heavy wet coats.
4. Improper spray gun set-up.
5. Improper painting technique.

Repair:

1. Compound or polish to reduce surface texture.
2. Or, sand smooth with 1200 or finer grit sandpaper, compound and polish to restore gloss.
3. Or, sand smooth and refinish.

Prevention:

1. Use proper reduction ratio and spray at recommended air pressure.
2. Select recommended thinner/reducer based on temperature, humidity, air movement and size of repair.
3. Avoid heavy coats and excessive film thickness.
4. Use recommended spray gun, fluid tip and air cap for the material being sprayed. Always adjust the gun for best atomisation and balanced spray pattern before paint application.
5. During paint application, hold the gun perpendicular and parallel to the surface. Adjust speed of pass, pattern overlap, and distance from the panel to achieve the desired appearance

What Causes Peeling?

1. Improper preparation of the substrate (sanding and cleaning).
2. Omitting or applying an incompatible undercoat to a specific substrate (e.g. aluminium, galvanised, plastics, etc).
3. Insufficient flash/dry time or exceeding the product’s maximum recoat time.
4. Insufficient film thickness of undercoat or topcoat.
5. Clearcoat finishes:
   1. Insufficient film thickness of clearcoat.
   2. Solvent cleaning basecoat before clearcoating,
   3. Sanding basecoat before applying additional basecoat or clearcoat.
   4. Basecoat applied too dry.
   5. Clearcoat applied too dry.
   6. Baking basecoat before applying clearcoat.
   7. Incompatible clearcoat.
   8. Use of incompatible ‘adhesion promoter’.
   9. Excessive basecoat film thickness.
   10. Over reduction, under reduction or incompatible reducer used in basecoat.

Repair:

1. Remove the finish in the affected area, feather edge and refinish.
2. Or, strip to bare substrate and refinish.

Prevention:

1. Clean and prepare all substrates according to product recommendations.
2. Use the recommended undercoat (primer) for the substrate being finished. Plastic parts may require use of special primer and flex additive for maximum performance.
3. Recoat all products within their recommended minimum and maximum recoat time.
4. Apply a sufficient number of coats to obtain the recommended film thickness.
5. Follow basecoat/clearcoat application procedures using only recommended/compatible products.
6. An ‘adhesion promoter’ should only be used when specifically recommended

What causes Pinholing?

Air or gas bubbles become trapped inside putty or filler during mixing or product application. These bubbles are exposed during the sanding process, creating small holes or craters in the surface.

Air or gas is trapped when:

1. Filler and hardener are mixed together using a ‘whipping’ motion (fast circular motion).
2. Adding too much hardener.
3. Applying heavy thick coats produces excessive heat, causing gas bubbles to form inside the product as it cures.

Repair:

1. Apply a thin layer of polyester glazing putty (properly catalysed and mixed), sand smooth and continue the repair process.

Prevention:

1. Mix putty/filler components by folding together and pressing down to eliminate air pockets.
2. Apply putty/filler in thin coats. Do not exceed manufacturer’s recommended total film thickness.
3. Follow manufacturer’s recommendation of correct ratio of putty/filler to hardener.

What causes Runs and Sags?

1. Over reduction and/or too slow evaporating thinner/reducer.
2. Applying paint materials without proper flash time between coats.
3. Applying excessive wet coats due to:
   a.  Holding the gun too close to the surface.
   b.  Slow gun speed.
   c.  Double coating.
4. Air pressure too low during spray application.
5. Improper spray gun set-up or an unbalanced spray pattern.
6. Material and/or substrate temperature too cold.

Repair:

1. Remove the wet paint film with solvent, clean and refinish.
2. Or, after finish is completely dry, remove excess paint by block sanding with 1200 or finer grit sandpaper, compound and polish to restore gloss.
3. Or, block sand smooth and refinish.

Prevention:

1. Mix according to product directions. Select recommended solvent for spray conditions based on temperature, humidity, air movement, size of repair.
2. Spray medium wet coats and allow sufficient flash time between coats.
3. Adjust the spray gun for the best atomisation and balanced spray pattern before paint application. Hold the spray gun perpendicular and parallel to the panel. Adjust speed of pass, pattern overlap and distance from the panel until the desired results are achieved.
4. Set air pressure at the gun according to product recommendations.
5. Use recommended spray gun, including fluid tip and air cap combination.
6. Allow the paint material and substrate to reach room temperature before application

What causes Sand Scratches?

1. Sanding the substrate with too coarse grit sandpaper.
2. Insufficient dry/cure of undercoats before sanding and topcoating.
3. Refinishing over soft, soluble substrates (e.g., lacquers, uncured OEM).
4. Using a poor grade and/or too fast evaporating thinners/reducers for spray conditions causing:
   1. Primer surfacer to ‘bridge’ over sand scratches.
   2. Topcoat to ‘skin over,’ trapping solvent which swells sensitive substrates.
5. Using a solvent cleaner that is too strong for the substrate or using thinner/reducer as a surface cleaner after sanding.

Repair:

1. Allow finish to dry/cure, sand smooth, compound or polish to restore gloss.
2. Or sand and refinish.

Prevention:

1. Sand with recommended grit sandpaper.
2. Allow undercoats to thoroughly dry/cure before sanding and topcoating.
3. Rub a small area of the old finish with a shop towel saturated with lacquer thinner. If the old finish is soluble or undercured, apply appropriate sealer.
4. Select recommended thinner/reducer based on temperature, humidity, air movement, and size of repair. Avoid ‘bridging’ existing scratches by applying primer surfacer in thin wet coats, allowing adequate flash time between each coat.
5. Use solvent cleaner designated for either lacquer (soluble) or cured enamel/urethane (insoluble) substrates

What Causes Seediness?

1. Material not properly stirred or agitated.
2. Failure to strain material.
3. Using material exceeding its shelf life.
4. Using generic reducers and/or hardeners.
5. Using materials beyond their specified pot life.
6. Using contaminated thinner/reducer or hardener.

Repair:

1. Remove the wet paint film with solvent, clean and refinish.
2. Or, sand smooth and refinish.

Prevention:

1. Stir or shake materials thoroughly to be sure all pigment/resin is in solution.
2. Strain all undercoats and topcoats.
3. Do not use material that cannot be stirred or strained. Caution: Repeated straining will not completely remove seediness.
4. Use the recommended thinner/reducer and hardener, and then measure accurately.
5. Mix only enough material that can be used within specified pot life.
6. Use material as soon as possible, close and tighten container lids immediately after use.

What Causes Shrinkage?

1. Topcoating before undercoats have thoroughly dried/cured.
2. Undercoats applied excessively wet with inadequate flash time between coats.
3. Undercoats under reduced.
4. Using a poor grade and/or too fast evaporating thinner/reducer for spray conditions.
5. Finishing over body filler that has not thoroughly cured.
6. Using too strong solvent cleaner or using thinner/reducer as a surface cleaner.

Repair:

1. Allow the affected area to thoroughly dry/cure, sand and refinish.
2. If additional filling is necessary, apply a primer surfacer, sand smooth and refinish.

Prevention:

1. Allow undercoats to thoroughly dry/cure before sanding and/or topcoating.
2. Thin or reduce undercoats according to product label directions. Apply in thin wet coats allowing adequate flash time between coats to avoid ‘bridging’ scratches.
3. Select recommended thinner/reducer based on temperature, humidity, air movement, and size of repair.
4. Follow body filler manufacturers recommended cure time.
5. Use solvent cleaner designated for either lacquer soluble or cured enamel/urethane insoluble substrate.

Cause:

Liquid solvent (thinners/reducers) becomes ‘trapped’ in the paint film when the surface layer skins over too quickly, preventing their evaporation into the atmosphere. Solvents that vaporize within the paint film leave bubbles, pinholes or craters as they push through and ‘pop’ the surface. Solvents can be trapped due to:

1. Thinner/reducer evaporating too fast for spraying conditions.
2. Inadequate flash time between coats.
3. Excessive film thickness or ‘piling on’ of heavy/wet coats.
4. Too much air movement causing surface to ‘skin over’ before solvents evaporate.
5. Excessive purge/flash time before force drying.

Repair:

1. Allow finish to thoroughly dry/cure, sand smooth and refinish. Inspect surface carefully to ensure all craters have been removed.
2. Severe popping will require removal of the affected film. Prime, seal and recoat, as necessary.

Prevention:

1. Select recommended thinner/reducer based on temperature, humidity, air movement and size of repair.
2. Allow for proper flash time between coats.
3. Avoid ‘piling on’ or double wet coats.
4. Restrict air movement over the surface being painted.
5. Avoid extended purge/flash time before force drying

What Causes Transparency?

1. Colour not thoroughly stirred/agitated.
2. Colour over-thinned/reduced.
3. Substrate not uniform in colour.
4. Wrong colour undercoat used.
5. Insufficient number of colour coats applied.

Repair:

1. Apply additional coats of colour until hiding is achieved.
2. Or, sand and apply similar coloured undercoat/ground coat and refinish.

Prevention:

1. Stir or shake paint material thoroughly, making sure all pigment is in solution/suspension.
2. Thin/reduce according to product label directions.
3. Use a sealer or ground coat to provide a uniform colour before topcoating.
4. Use an undercoat that is similar in colour to the topcoat.
5. Spray until hiding is achieved.

Note: Spray monitors (hiding power labels, opacity charts) provide a contrasting feature by which to observe the hiding power or transparency of topcoat colour during spray application. When black and white can no longer be seen through the colour complete coverage is achieved

What Causes Water Spotting?

1. Allowing water to come into contact with a finish that is not thoroughly dried or cured.
2. Washing finish in direct sunlight.

Repair:

1. Wipe with a damp cloth, then polish.
2. Or, compound and polish.
3. Or, sand smooth with 1500-2000 grit sandpaper, compound and polish to
4. Or, sand and refinish.

Prevention:

1. Do not allow water to come into contact with newly painted finish.
2. If a new finish does get wet, dry immediately with a soft cloth.
3. Wash new finishes in the shade and wipe dry

What Causes Wrinkling?

1. Excessive film thickness or ‘piling on’ of heavy wet coats.
2. Placing a newly painted finish in hot sun too soon after spraying.
3. Using lacquer thinner to reduce synthetic enamel.
4. Spraying in extreme hot, humid weather conditions.
5. Under reduced and/or too fast evaporating thinner/reducer for spray conditions.
6. Air pressure too low during spray application.
7. Force drying of air-dry enamels without the recommended additives.

Repair:

1. If defects are minor: sand the top surface smooth and allow to cure, then refinish.
2. If defects are severe: remove the affected area and refinish.

Prevention:

1. Avoid excessive film thickness and heavy coats. Always allow for sufficient flash times.
2. Keep newly painted finish away from direct sunlight until finish has dried/cured.
3. Use reducer that is specifically recommended for the topcoat.
4. Use the recommended reducer, additive, and/or retarder when spraying in hot humid weather.
5. Select recommend thinner/reducer based on temperature, humidity, air movement, and size of repair.
6. Use the proper reduction ratio and spray at recommended air pressure.
7. Select the recommended additives to suit drying conditions. Follow force dry temperatures and time recommendations