After touch-up painting, it's obvious at a glance that it has been "patched" — this is the worst review a repair job fears. Color difference can be major or minor; the key lies in identifying the right cause and using the correct technique.
I. Where does color difference come from?
- Color code/formula inaccurate: The correct color code was not found or the fine-tuning was insufficient.
- Construction differences: Film thickness, angle, flash-off, and adjacent surfaces differ, metallic paint is especially sensitive.
- Poor blend: The boundary between old and new paint is sharp, forming a "color patch".
II. Overspray Method
In the damaged area, spray thin multiple layers toward the old paint direction with decreasing concentration, allowing the new paint to blend naturally and eliminate hard edges. Using a blend-in solvent to soften the finishing edge is the mainstream technique for local repair to eliminate color difference.
III. Panel Alignment Techniques
Test panels must be sprayed with the same process and environment as the target part, compared under natural light from two angles, and the formula fine-tuned and reapplied if necessary. Better to compare a few more times on the panel than to rework on the vehicle.
Summary
Color difference arises from deviations in color code, formula, and application. Reducing color difference relies on blend spraying to eliminate boundaries and confirming the formula against a panel using the same process; for metallic/pearl paints that are difficult to blend or for panels with extensive damage, full-panel repainting is preferred.
Frequently Asked Questions (FAQ)
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