Common Paint Problems and Solutions

Problem	Appearance	Cause	Remedy	Prevention
Acid & Alkali Spotting	Irregular shaped pitting, etching or discoloration of paint film	Chemical change occurring from harmful contaminants	a. Sand and buff b. Sand and refinish c. If reached metal must be stripped	a. Keep away from contaminated atmosphere b. Wash immediately after contamination
Bleeding	Discoloration of the surface of the refinish color	Solvent penetration from fresh color dissolves old finish	a. Remove all color coats and refinish b. Allow surface to cure then isolate with 2K undercoat and refinish	Apply 2K undercoat or sealer over suspected problem areas
Blistering (Solvent Pop)	a. Small pin-sized bubbles b. Small swelled areas like a water blister on skin	a. Rust under surface b. Trapped solvent c. Moisture in air line d. Prolonged exposure to high humidity	Sand out blisters or solvent pops and refinish	a. Avoid use of fast reducer when temp is high b. Allow proper dry time between coats
Blushing	The finish turns milky immediately or shortly after application	a. Fast reducer in high humidity b. Unbalanced reducer c. Condensation on old surface	a. Add retarder to reducer and recoat b. Sand and refinish	a. Use good quality reducer b. Keep paint and paint surface room temp c. Use retarder on hot or humid days
Chalking	Lack of gloss or a powdery surface	a. Natural weathering of paint film b. Lack of thorough agitation of paint c. Using paints and solvents of low quality	a. Polish to restore gloss b. Sand and refinish	a. Use quality products b. Keep paint surface clean with occasional waxing c. Thoroughly agitate all paint materials
Checking, Crazing, Cracking	a. Crowfoot (checking) b. Shattered Glass (crazing) c. Splits or separation (cracking)	a. Using improper reducer b. Excessive film thickness c. Insufficient dry time of film d. Extreme temp change	Remove finish down through checked or cracked area and refinish	a. Allow proper dry time b. Use sealer c. Use compatible products d. Avoid temp change
Dieback (Dull Finish)	Gloss becomes dull as film dries or ages	a. Compounding before solvent evaporates/cures b. Using poorly balanced reducer c. No flash time between coats d. Topcoats applied on wet undercoats	Allow to cure before polish, then sand and refinish	a. Allow proper dry time b. Use top-quality materials c. Use a well-balanced reducer
Edge Mapping	Raised or lifted edges in wet or dry paint film	Solvent from new topcoat penetrates a solvent-sensitive substrate	Sand smooth with 400 grit or finer Isolate affected area with 2K primer and refinish	Use 2K primer or waterborne surfacer Avoid sanding through topcoat
Fisheyes	a. Cratering of the wet film b. Small craters formed in topcoat	a. Spraying over surfaces containing silicone b. Improper cleaning of old surfaces	Add fisheye eliminator and recoat	a. Clean surface with wax and grease remover b. Use fisheye eliminator c. Use clean air supply
Lifting	Raising or swelling of the wet film, Peeling of dry film	a. Exceeding max flash time during application b. Recoating where clearcoat has insufficient film build	a. Do not exceed max recoat time b. Seal old finishes and recoat	a. Allow undercoats to dry fully b. Seal old finishes, especially if enamel or lacquer
Mottling	Streaking of color, generally associated with metallic colors	a. Excessive wetting of paint b. Improper spray technique c. Uneven film thickness	a. Back away and increase air pressure for final coat b. Avoid over-reducing paint c. Allow base coat to flash	a. Avoid excessive film build b. Do not over-reduce
Orange Peel	Paint film having texture resembling the skin of an orange	a. Wrong temp reducer b. Improper gun setup c. Under reduction or low pressure	a. Sand and buff b. Sand and refinish	a. Proper reduction b. Proper gun setup and spray technique
Peeling (Delaminating)	Loss of adhesion or separation of paint film from substrate	a. Improper surface prep b. Insufficient flash time c. Insufficient film thickness d. Excessive base coat thickness	Remove peeling paint completely and refinish	a. Thoroughly clean all substrates b. Follow acceptable refinish procedures
Pin Holes	a. Small pinpoint holes in finish b. Air bubbles raising the film and causing craters when erupted	a. Excessive amount of hardener b. Applying heavy thick coats causing heat buildup	Sand thoroughly and apply a coat of polyester putty	a. Mix proper amount of hardener b. Do not exceed manufacturer filler thickness
Plastic Filler Bleed-Thru	Discoloration of topcoat color, usually yellowing on light colors	a. Too much hardener b. Applying topcoat before plastic is cured	a. Remove filler patch b. Cure topcoat, sand, and refinish	a. Use correct amount of hardener b. Allow adequate cure time
Plastic Filler Not Drying	Stays soft after applying	a. Insufficient amount of hardener b. Hardener exposed to sunlight	Scrape off plastic and re-apply	a. Add recommended amount of hardener b. Ensure not exposed to sunlight
Runs & Sags	a. Running of wet film in rivulets b. Mass slippage of paint film	a. Over-reduction or low air pressure b. Painting on cold surfaces c. Holding gun too close	a. Wash with solvent and refinish b. After drying, sand and refinish	a. Mix to directions with proper solvent b. Allow paint and substrates to reach room temp
Sand Scratches	Visible lines or marks in paint film following sanding marks	a. Using too fast of a reducer b. Sanding with too coarse grit paper c. Refinishing over soft substrates	Sand and refinish	a. Select proper reducer for temp b. Sand with proper grit sandpaper
Stone Bruises	Small chips of paint missing from an otherwise intact finish	Loss of adhesion due to impact (e.g., stones, car doors)	Sand/featheredge the damaged area and refinish	Use premium 2K undercoat and topcoat systems
Transparency	Original finish or undercoat visible through topcoat	a. Over-reduced paint b. Substrate not of uniform color c. Color not stirred or agitated	Sand and refinish	a. Reduce paint according to instructions b. Use sealer to provide uniform color
Wet Spots	Discolored and/or slow drying spots of various sizes	a. Reducing paint with improper solvent b. Excessive heavy undercoat not properly dried	Sand or wash off thoroughly and refinish	Use only water as a sanding lubricant
Wrinkling	a. Puckering effect b. Resembles skin of prune	a. Under-reduced paint or air pressure too low b. Fast reducers c. Excessive coats	Break top surface by sanding, allow paint to dry thoroughly	a. Do not force dry until solvents have flashed off b. Apply as recommended

Clean air supply, free of moisture and contaminates, is a necessity for problem free paint application.

*Excessive moisture in airlines **Contaminated airlines