Expert solutions for common automotive touch up paint problems. Fix issues with paint pens, spray cans, clearcoat, and application techniques.

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Paint Pen Problems
Shine & Finish Issues
Spray Application Defects
Peeling & Adhesion
Color Matching Problems
Drying & Curing Problems

Paint Pen Problems

Leaking Paint Pen – Paint Too Thin

Symptom: Paint runs out quickly and appears watery or very thin when applied. The felt tip becomes oversaturated.

Primary Solution:

The paint formula was likely mixed too thin. Contact PaintScratch customer service with your order information for a replacement paint pen.

Application Techniques to Try:

• Float the paint: Apply a thin layer while barely touching the surface. This technique requires practice – test on scrap material first
• Extend drying time: Ensure each coat is completely dry before reapplying (30-60 minutes depending on temperature)
• Prepare the nib: Depress the pen, wipe excess paint, ensure the tip is properly wetted, then reapply
• Control temperature: Apply paint below 80°F. Higher temperatures dry paint on the nib too quickly
• Clean regularly: Rinse nib in automotive lacquer thinner to keep it soft and flowing smoothly

Important: Use only automotive lacquer thinner (available from PaintScratch or auto body supply stores). Regular hardware store lacquer thinner will damage the felt nib.

Paint Pen Won’t Flow – Paint Too Thick

Symptom: Depressing the tip produces no paint flow, or paint comes out very thick and pasty.

Common Causes:

• Paint dried around the valve mechanism
• Felt nib is clogged with dried paint
• Paint mixed too thick by manufacturer
• Pen exposed to high temperatures during storage

Solutions:

1. Remove the felt nib from the pen
2. Soak both the pen body and nib in automotive lacquer thinner for 15-30 minutes
3. Shake pen thoroughly after reassembling
4. If paint still won’t flow properly after cleaning, request a replacement

Paint Flows Too Fast

Symptom: Paint runs out like water when you depress the tip, making controlled application impossible.

Solutions:

• First step: Shake the paint pen thoroughly for 2-3 minutes. Pigments may have settled
• If still too thin: The formula was mixed incorrectly. Contact us for replacement

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Shine & Finish Quality Issues

Poor or No Shine After Clearcoat

Symptom: Finished repair appears dull, cloudy, or lacks the glossy shine of surrounding paint.

1. Incorrect Polishing Compound

• Problem: Using polishing compound (too fine) or heavy-duty rubbing compound (too aggressive)
• Solution: Use medium-duty rubbing compound with a clean, soft cotton cloth (old t-shirt works best)
• Technique: Apply compound in circular motions with moderate pressure until high gloss appears

2. Insufficient Clearcoat

• Problem: Polishing through clearcoat into basecoat layer. Basecoat will never shine
• Solution: Apply 2-3 additional coats of clearcoat (wait 10-15 minutes between coats), then polish again

3. No Clearcoat Applied

• Problem: Skipped clearcoat step entirely (more common than you’d think!)
• Solution: Apply clearcoat in 2-4 light coats, allow to cure 24 hours, then polish

Fine Scratches in Clearcoat After Polishing

Symptom: Clearcoat shows fine scratches, swirl marks, or haze after using rubbing compound.

Solutions:

• Apply additional clearcoat if you’ve polished too deep
• Switch to soft, clean 100% cotton cloth
• As final step, use very fine polishing compound to remove micro-scratches
• Ensure future applications in proper conditions (60-75°F, below 50% humidity)

Paint Blob or Raised Area

Symptom: Paint forms a ball or blob instead of spreading smoothly. Creates raised, uneven texture.

Removal Technique:

1. Apply automotive lacquer thinner to a soft, lint-free cloth
2. Wrap cloth around a popsicle stick or similar tool
3. Gently wipe back and forth across the blob to dissolve and level excess paint
4. Work carefully to avoid removing too much paint
5. Alternatively, use rubbing compound to reduce blob height
6. Do NOT use sandpaper – it will dull surrounding finish

Prevention Tip: Cool both the painted surface and the paint pen before application. Lower temperature increases working time, allowing paint to spread and level properly.

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Spray Application Defects

Fish Eyes

Symptom: Crater-like circular defects where paint pulls away from center, resembling fish eyes. Occurs immediately upon spraying.

Causes: Surface contamination prevents proper paint adhesion

• Water residue (from wet sanding or humidity)
• Oil or grease contamination
• Silicone (from polish, wax, or environmental sources)
• Wax and grease remover left on surface too long before wiping

Solution – Complete Restart Required:

1. Remove all paint using automotive lacquer thinner wash
2. Do NOT attempt to sand and repaint – contamination will persist
3. Re-clean surface thoroughly with wax and grease remover
4. Wipe immediately (don’t let dry on surface)
5. Ensure all water from wet sanding is completely removed
6. Reapply paint in controlled, clean environment

Spider Veins or Webbing

Symptom: Web-like pattern of lines where paint appears textured and doesn’t flow together smoothly.

Solutions:

• Spray distance: Hold spray can or gun 6-8 inches from surface
• Temperature: Paint only when temperature is between 60-75°F
• If already sprayed: Sand affected area smooth and repaint with correct technique

White Haze or Streaks (Blushing)

Symptom: Clearcoat appears cloudy white or has milky streaks. May look hazy or opaque instead of crystal clear.

Prevention & Fix:

• Prevention: Paint only when humidity is below 50% and temperature is 60-75°F
• To fix existing haze: Lightly scuff the hazed clearcoat with 1000-grit sandpaper, apply additional color coat if needed, then reapply clearcoat in proper conditions

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Peeling & Adhesion Problems

Peeling Paint

Symptom: Paint peels away in sheets or flakes from the surface.

Common Causes:

• Surface contaminated with wax or oil
• Painting over unprimed metal surface
• Not using SEM adhesion promoter on non-metal surfaces (plastic, fiberglass)
• Insufficient surface preparation

Solution:

1. Remove all peeling paint completely
2. Clean and degrease surface thoroughly
3. Apply appropriate primer (or SEM adhesion promoter for plastics)
4. Reapply basecoat and clearcoat following proper procedure

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Color Matching Problems

Metallic Paint Appears Too Dark

Symptom: Metallic touch up paint looks noticeably darker than surrounding factory paint.

Why This Happens:

Metallic flakes lay at different angles when hand-applied versus spray-applied. Each flake acts like a tiny mirror. Brush or pen application cannot match the spray pattern that controls flake orientation, resulting in darker appearance.

Solutions:

• Use rubbing compound to help blend and lighten slightly
• For repairs larger than a dime, spray application with proper blending is necessary
• Limit brush/pen repairs to very small chips for best results

Visible Tape Lines

Symptom: Clear boundary line visible where tape was removed, creating sharp edge between new and old paint.

Solutions:

• Never tape in the middle of a body panel
• Use blending techniques – feather paint edges beyond repair area
• Gradually thin coats toward edges
• Polish transition areas with rubbing compound to blend the edge
• Extend repair area and blend new paint into surrounding finish

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Drying & Curing Problems

Clearcoat Remains Soft

Symptom: Clearcoat indents easily with fingernail pressure after what should be adequate drying time.

Common Causes:

• Clearcoat applied before basecoat fully dried (needs 30-60 minutes)
• High humidity mixing water vapor into paint during application

Solution:

Allow several weeks for complete curing without testing. Avoid touching or testing with fingernails. If water contamination occurred (visible in spray gun water trap), you may need to remove all paint and restart with humidity below 50%.

Solvent Pop (Tiny Bubbles)

The tiny bubbles in the pictures are called solvent pop. Two things cause it, either the application is rushed and uncured coats of primer or paint are being trapped under the clearcoat. The second cause could be in compatibility of whatever is under the new material that was applied and the solvents in the clearcoat are attacking it.