Transcript PowerPoint プレゼンテーション

Paint Defects 1
(1) Cratering
(2) Dust (nibs)
(3) Orange peel
(4) Sagging
(5) Poor opacity
Cratering / Fish-eyes
Cratering
(phenomenon from base material)
Fish-eyes
(phenomenon in paint film layer)
Cratering and Fish-eyes occurs partly on the paint surface, and the film becomes uneven.
Cratering / Fish-eyes (cause-result analysis chart)
Application work
Drying
Poor drying of putty
Too thick application of excessively diluted
paints
Thick application of lacquer type putty
Cratering
Strong dissolvability of topcoat paint.
Insertion of polyester putty between lacquer
paint films
Poor sanding of putty
Absorptive putties
Excessive adding of non-blushing
thinner
Paint / Putty
Others
Cratering / Fish-eyes
Measures
Circumstances
Precautions
Most of the troubles can be
resolved by avoiding the factors
Facility & Equipment
Application work
Materials
Slight fish-eyes shall be repaired with dry mist spraying.
Remedy
Large sized (cratering) shall be abraded off
completely after drying, and repaint.
Dust (Nibs)
Popping
Popping appears on the film surface.
Dust (cause-result analysis chart)
Materials
Facility & Equipment
Shortage of booth air pressure
Insufficient filtration of paint
Defects of booth filters
Insufficient cleaning of spray guns
Defects of air cleaner
Dust
Dusty working clothes
Insufficient cleaning of
the painting work floor
Insufficient cleaning of car body
Trash of masking papers (newspapers, etc)
Insufficient cleaning of spray gun
Circumstances
Application works
Dust (Nibs)
Measures
Precautions
Keep painting area clean, and free from trashes and dusts.
Prevent working area from floating dusts by watering the
floor before painting.
Wear anti-dust working clothes, and use proper masking
paper and tapes.
Remedy
Abrade off small nibs with a knife or grinding stone, and
polish it up with compounds
Orange peel
Paint surface become uneven like orange peel.
Orange peel (cause-result analysis chart)
Application works
Circumstances
High temperature of car body
Too fast blowing speed
Thin paint film
Low spray pressure
Insufficient spraying emission volume
High temperature
Too fast gun speed
Too long spray gun distance
Orange peel
Too quick evaporation of thinner
Too big size of spray gun nozzle
(insufficient atomization of the paint)
Too high viscosity of thinner
Low liquidity of paint
Materials
Defects of spray pattern
(insufficient cleaning of spray gun)
Facility & Equipment
Orange peel
Measures
Slow evaporation speed of solvent
Precautions
Decrease viscosity of paint.
Maintain liquidity of paint
Remedy
Apply water sanding (#800～#1000), and polish up
gradually with compounds (Medium→Fine→Extra fine).
Sagging
Substrate
Paint film partly becomes too thick and the paint sags.
Paint film
Sagging (cause-result analysis chart)
Circumstances
Application work
Low temperature of car body
Thick paint film
Low temperature
Low spray pressure
Too short spray gun distance
Too much spraying emission volume
Defective spray pattern
Sagging
Too slow evaporation of thinner
Too big size of spray gun nozzle
(insufficient atomization pf paint)
Too low viscosity of paint
Defective spray pattern
Materials
Facility & Equipment
Sagging
Measures
Make set-to-touch time faster
Precautions
Adjust spray pattern, gun distance, and gun speed to proper
level.
Use proper thinner to avoid excessive coating.
Overall sagging : abrade off whole area, and refinish.
Remedies
Slight sagging : abrade off the sagging area, then apply
compound (fine→extra fine )
Poor opacity (Poor hiding power, or Lack of hiding)
Poor pigmentation
Insufficient film thickness
The color of undercoat is not hidden caused by poor pigmentation, or insufficient film thickness
Poor opacity (cause-result analysis chart)
Application works
Insufficient agitation
Too thin film coating
Too much diluted
Poor opacity
Specific nature of tinter
Materials
Lack of hiding power
Poor opacity
Measures
Spray paint in proper film thickness after sufficient agitation
Precautions
Avoid excessive dilution.
Apply back-up undercoat of similar color shade in
case of poor hiding colors.
Remedy
Repaint until the undercoat is completely hidden.