I-CAR Refinishing and Color Matching 5

Question 1

What is 'dieback' in a clearcoat finish?

Accepted Answer

A loss of gloss after curing, often from the clear sinking into the substrate

Answer

Dieback occurs when the clearcoat is absorbed into the layers beneath, dulling the finish after it initially looked glossy.

Question 2

What causes solvent pop?

Accepted Answer

Trapped solvents escaping through a surface that has already skinned over, such as from heavy films or insufficient flash

Answer

Solvent trapped under a skinned film forms small blisters or pinholes as it escapes.

Question 3

What is the usual procedure to correct minor orange peel in cured clearcoat?

Accepted Answer

Wet sand with fine abrasive and then compound and polish

Answer

Leveling with fine wet sanding followed by polishing restores smoothness and gloss.

Question 4

Why must catalyzed paint products be mixed exactly to the specified ratio?

Accepted Answer

Incorrect ratios can cause poor cure, reduced durability, and film defects

Answer

Wrong hardener or reducer proportions compromise cross-linking and the finish properties.

Question 5

What type of respiratory protection is recommended when spraying isocyanate-containing paints?

Accepted Answer

A supplied-air respirator or a properly fitted respirator approved for isocyanates

Answer

Isocyanates are respiratory sensitizers, and supplied-air respirators are the preferred protection.

I-CAR - Inter-Industry Conference on Auto Collision Repair Certified Practice Test