Colour Matching, Tinting, and Mixing
What the exam tests
This domain tests colour matching, variant selection, tinting, and mixing. Expect questions on colour theory, metallic and pearl orientation, spray-out cards, blending, mixing by weight, pot life, and why a match can look right under one light and wrong under another.
Core rules
- Start with the vehicle colour code and then select the variant that matches the actual panel. OEM colours vary by plant and year; a code is a starting point, not a guarantee.
- Mix by weight on a calibrated scale using the current formula. Volume measurement is not accurate enough for tinting, and uncalibrated scales cause repeatable errors.
- Stir and strain according to the system. Add tint in small increments and record the addition so the match can be repeated.
- Judge colour under a consistent light source and at the correct angle. Metallic and pearl colours have face, side, and flop; check a spray-out over the recommended sealer, then clear it if the system requires.
- Use a letdown panel or spray-out card to compare the repair colour with the adjacent panel. For blends, apply base beyond the repair and use a blender or drop coat as specified.
- Respect pot life and induction time. Activated products that sit too long may lose flow, adhesion, or gloss.
Worked example
A silver fender looks too dark and muddy beside the door. The technician confirms the code and variant, sprays a card over the same sealer, and compares face and side tone. If the card is close but the panel is not, the difference may be flake orientation from gun distance or a wet versus dry coat, not the tint. The fix is to correct technique and blend, not to dump in more tinter.
Traps that cost marks
- Matching under a single fluorescent light.
- Mixing by volume or eyeballing tint.
- Sanding metallic basecoat before clear.
- Over-tinting before checking a spray-out and the sealer under the colour.