Thinning is not generally required when brushing Motor Coater, but if needed, 5–10% is normally adequate. Use KBS #1 Thinner or Xylene only — both are slow evaporating solvents that work exceptionally well with Motor Coater.
💡 Pro Tip — Let the Brush Marks Flow Out
Apply Motor Coater in thin coats and resist the urge to go back over the same area repeatedly. Overbrushing forces the solvents out of the coating before they can do their job — the result is brush marks that won't flow out as designed. Brush it on, then leave it alone and let it self-level.
Before you begin, review the complete Motor Coater application instructions for full prep, thinning ratios, and brushing guidance.
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