Paint Mixing Ratio Calculator.
Calculate compound mixtures for industrial epoxies, polyurethane coatings, and automotive spraying paints.
Compound Proportioning
Example: A standard automotive clear coat ratio of **4:1:1** means 4 parts paint, 1 part hardener, and 1 part reducer.
Understanding Paint Chemical Mixing.
Why exact ratios are critical
Unlike standard wall latex paints which dry solely by water evaporation, two-component (2K) paints like epoxies or polyurethanes dry by a chemical cross-linking reaction between resin (Part A) and activator (Part B).
Adding too much or too little hardener will disrupt this stoichiometry, leaving the coating soft, tacky, or brittle. Reducer/thinner (Part C) is added strictly to reduce paint viscosity for spraying, and does not alter the core curing reaction.
How to mix safely
Always mix components thoroughly in a clean, straight-sided beaker. Stir slowly to prevent whipping air bubbles into the paint. Pay attention to the paint's **pot life**—the length of time the mixed paint remains liquid and sprayable before gelling.
*Warning: Curing epoxies undergo an exothermic reaction. Large mixed batches left inside a bucket can generate high heat and smoke.*