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Bubbles are a common challenge when colouring resin, especially if you want a flawless and professional-looking finish. Thankfully, a few straightforward preparation and mixing techniques can help minimise or eliminate these unwanted bubbles.
Tips for Mixing Resin Without Trapping Bubbles
The key to reducing bubbles is to stir the resin and colourant slowly and steadily rather than with quick or vigorous motions. Fast or forceful stirring folds air into the mixture and leads to cloudy results. Always use a clean mixing tool and move deliberately, scraping the sides and base of your container to ensure an even blend while keeping agitation to a minimum. Additionally, only pour after the pigment is fully dispersed so the resin flows smoothly and evenly.
Letting the Resin Rest Before Pouring
Once your coloured resin is thoroughly mixed, let it sit uncovered and undisturbed for several minutes. This simple step allows air bubbles to rise naturally to the surface, where they can dissipate. For added effectiveness, tap your mixing container gently on the workbench to encourage trapped bubbles to escape. If bubbles gather on the surface, use a cocktail stick, fine tool, or gentle breath to pop them before pouring the resin into your mould or onto your surface.
Choosing the Right Additives and Tools
Some additives, like metallic glitters or high-density pigments, may slightly increase the chance of trapping air. Selecting quality products designed for resin crafts—such as the Phosphorescent Pigment – Glow-in-the-Dark Additive—helps ensure a smoother mix. Opt for thin, flat mixing sticks and use shallow containers whenever possible, as deeper vessels can make it harder for bubbles to escape effectively.
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By slowing your mixing speed, allowing your resin to settle, and taking care with materials, you’ll achieve clearer, more professional-coloured resin results. If you’re interested in further guidance on how to colour polyester resin for your project, visit our main advice page for expert tips and inspiration.