How to Thin paints for airbrushing
Airbrushing with acrylic paints opens up a world of creative possibilities. However, achieving smooth results requires properly thinning your paints. Let’s talk about how to properly thin paints to avoid headaches when airbrushing a model.
Why Proper Thinning is Essential
Acrylic paints are typically too thick for airbrushes straight out of the bottle. Without proper thinning, your airbrush may clog, sputter, or create uneven coverage. Thinning your paint correctly ensures:
Smooth application without clogging the nozzle.
Better atomization, allowing for fine details and gradients.
Consistent flow, reducing interruptions during painting.
Choosing the Right Thinner
Different thinning options are available, each with unique properties. Here are the most common choices:
1. Airbrush Thinner
Specifically formulated for airbrushing, commercial airbrush thinners maintain paint integrity while reducing viscosity. They often contain binders that prevent pigment separation and improve adhesion.
2. Distilled Water (NOT TAP WATER!)
A cost-effective and easily accessible option, distilled water can thin acrylics effectively. However, excessive dilution may weaken adhesion and coverage, requiring multiple layers. The minerals in tap water can lead to inconsistent results and unexpected side effects with the pigment of the paints.
3. Airbrush Medium
Similar to commercial thinners, airbrush mediums are designed to dilute acrylic paint while preserving its properties. They help maintain pigment stability and extend drying time for better blending.
How to Thin Acrylic Paint for Airbrushing
Step 1: Determine the Right Consistency
Acrylic paint should have a skim milk-like consistency for airbrushing but what does that mean? Your paint should be thin enough that it runs down the side of your mixing cup, but not so thin it resembles water. If your paint doesn’t run it’s too thick!
Step 2: Mix Your Paint and Thinner
Start with a 1:1 ratio (one part paint to one part thinner) and adjust as needed. Some paints may require more or less thinning depending on brand and consistency.
For fine detail work, use a thinner mix (e.g., 2:1 thinner to paint).
For base coats, a slightly thicker mix (e.g., 3:2 paint to thinner) may work better.
Step 3: Test and Adjust
Before spraying your final piece, test the mixture on a scrap surface. If you see paint spattering or your airbrush isn’t releasing an even flow it’s too thick. If you’re experiencing the paint running on the model, or not leaving enough color it’s too thin.
(Optional) Step 4: Strain the Mixture
One thing many painters do is strain their paint through a paint strainer, to make sure there aren’t any hidden clumps or debris in your paint that could clog your airbrush. I don’t recommend mixing in the airbrush cup to start, as you may miss some clumped together paint blobs!
Step 5: Keep Your Airbrush Clean
Acrylics dry quickly, so frequent cleaning is essential. Flush your airbrush with water or cleaner between color changes and perform a deep clean after each session to prevent buildup.
Pro Tips for Airbrushing with Acrylics
Use low to medium air pressure (20-30 PSI) for better control.
Work in thin, even layers to build up color gradually.
Avoid over-thinning, as it can cause poor adhesion and excessive transparency.
Experiment with different thinners to find the best combination for your specific paint brand.