To make acrylic paint thicker using cornstarch, you first need to prepare a cornstarch-based thickener, then carefully mix it into your acrylic paint. This method allows you to achieve a more textured, impasto effect with your artwork.
Preparing the Cornstarch-Based Thickener
The initial step involves creating a thick, gel-like substance from cornstarch and water. This cooked mixture will be the agent that adds body to your acrylic paint.
Ingredients for Cornstarch Thickener
| Ingredient | Quantity (US Standard) | Quantity (Metric) |
|---|---|---|
| Water | 2 cups | 470 mL |
| Cornstarch | 3 tbsp | 14.3 g |
Step-by-Step Thickener Preparation
- Combine Ingredients: In a saucepan, mix 2 cups (470 mL) of water with 3 tbsp (14.3 g) of cornstarch. Ensure the cornstarch is fully dissolved in the cold water to prevent lumps when heated.
- Boil and Thicken: Place the saucepan on a stove and boil the mixture until it thickens. Stir continuously over medium heat. The mixture will transition from a milky liquid to a clear, viscous gel. Once it reaches a consistency similar to a thick syrup or gel, remove it from the heat. Allow it to cool completely before proceeding, as hot thickener can affect paint properties.
Integrating the Thickener with Acrylic Paint
Once your cornstarch thickener has cooled, you can begin to incorporate it into your acrylic paint.
- Prepare Your Paint: Spread out the paint on a palette or dish. This provides a good surface for mixing and allows you to control the amount of paint you are thickening.
- Gradual Mixing: Add small amounts of the prepared cornstarch thickener to your acrylic paint. Begin with a very small quantity, such as a pea-sized dollop for a small amount of paint.
- Thorough Blending: Using a palette knife or brush, thoroughly mix the thickener into the paint. Continue mixing until you achieve a smooth, even consistency.
- Test and Adjust: Test the consistency of the thickened paint. If you desire a thicker texture, gradually add more of the cornstarch thickener, mixing well after each addition, until you reach your desired viscosity.
Tips for Best Results
- Start Small: Always begin with a small amount of thickener and gradually add more. It's easier to add more thickener than to thin out overly thick paint.
- Lump-Free: Ensure your cornstarch thickener is completely smooth and lump-free before mixing it into your paint. Lumps in the thickener will result in a grainy texture in your finished paint.
- Cool Down: Always let the cornstarch mixture cool down completely before adding it to your paint. Hot mixtures can affect the paint's color, drying time, or chemical stability.
- Consistency: The cornstarch thickener will create a matte finish and a paste-like texture. If you desire a different sheen, you may need to apply a varnish after the paint dries.
- Storage: Store any leftover cornstarch thickener in an airtight container in the refrigerator for a few days. However, it's best to prepare fresh batches as needed for optimal results, as cornstarch paste can spoil over time.
