Why Does My Resin Art Have Bubbles And How To Fix It Next Time

Resin art is a captivating medium that allows artists to create glossy, glass-like finishes with vibrant colors and intricate designs. But even experienced crafters face a common frustration: bubbles. Tiny air pockets can appear in cured resin, marring an otherwise perfect piece with cloudy spots or visible imperfections. While bubbles are normal during the mixing and pouring process, they don’t have to ruin your work. Understanding why they form—and how to eliminate them—is essential for achieving professional-quality results.

Bubbles aren't just cosmetic issues; they can also weaken the structural integrity of thicker pours and compromise clarity in detailed work. The good news is that most bubble problems are preventable with the right materials, techniques, and timing. By identifying the root causes and applying targeted solutions, you can significantly reduce or even eliminate bubbles from your resin projects.

Why Bubbles Form in Resin Art

Air becomes trapped in resin at multiple stages—from mixing to curing. The chemical reaction between resin and hardener generates heat (exothermic reaction), which can cause trapped air to expand and rise. However, if not properly managed, these bubbles get locked in as the resin begins to cure.

The primary sources of bubbles include:

• Mixing technique: Vigorous stirring introduces air into the liquid resin.
• Pouring method: Pouring from a height creates splashes and turbulence that trap air.
• Material interactions: Porous substrates like wood, paper, or dried botanicals release moisture and air when covered in resin.
• Temperature fluctuations: Cold environments slow curing and allow bubbles more time to rise, while hot spots can accelerate surface skinning before bubbles escape.
• Additives and pigments: Some colorants, especially powdered micas or alcohol inks, introduce volatility or outgas during curing.

Even high-quality resins are susceptible to bubbling under suboptimal conditions. According to Sarah Lin, a resin artist with over a decade of experience, “I used premium epoxy for years but still struggled with bubbles until I realized it wasn’t the product—it was my process.”

“Most bubble issues stem from user error, not material failure. Control your environment, refine your pour, and use gentle mixing—those three changes alone solve 90% of bubble problems.” — Sarah Lin, Resin Artist & Educator

How to Prevent Bubbles Before They Form

Prevention is always better than correction. Once resin starts curing, removing bubbles becomes increasingly difficult. The following steps should be integrated into every resin project to minimize risk.

1. Mix Slowly and Thoroughly

When combining resin and hardener, avoid whipping or rapid stirring. Use a slow, deliberate motion, scraping the sides and bottom of the container to ensure complete blending without incorporating excess air. Stir for at least 3 minutes, depending on batch size, ensuring no streaks remain.

Tip: Scrape the stir stick along the container walls frequently to break any hidden air pockets forming near the edges.

2. Condition Your Materials

Bring both resin and hardener to room temperature (72–75°F or 22–24°C) before use. Cold resin is thicker and more likely to trap air during mixing. Let bottles sit in a warm area for 24 hours prior to pouring—never heat them in microwaves or ovens.

3. Seal Porous Surfaces

Wood, fabric, dried flowers, and paper all contain tiny air pockets and moisture. Apply a thin seal coat of resin first and let it cure completely before adding your main pour. This seals off escaping gases and prevents \"late-stage\" bubbling.

4. Pour Close to the Surface

Always pour resin as close to the substrate as possible. Hold your cup low and dispense slowly to minimize splashing. Consider using a spout or squeeze bottle for greater control.

5. Work in a Stable Environment

Drafts, fans, and HVAC vents disturb the surface tension and cool the top layer too quickly. Maintain a stable workspace free from airflow, humidity spikes, and direct sunlight.

Effective Methods to Remove Bubbles After Pouring

Even with careful preparation, some bubbles may still appear. Fortunately, several tools and techniques can remove them before the resin sets.

Using a Heat Source

A lighter pass with a torch is one of the most effective ways to pop surface bubbles. Pass the flame quickly over the surface—do not hold it in place. The brief heat thins the resin slightly and causes bubbles to burst and collapse. Butane micro-torches are preferred because they offer precise control.

Alternative: A heat gun can be used, but keep it on the lowest setting and maintain distance to avoid ripples or yellowing.

Blowing Gently Through a Straw

In situations where tools aren’t available, gently blowing across the surface through a straw can dislodge small bubbles. Do not breathe directly onto the resin, as moisture from your breath can create fisheyes or cloudiness.

Tapping the Mold or Frame

For smaller pieces, firmly tap the sides of the mold or table surface to encourage bubbles to rise. Do this immediately after pouring and repeat lightly over the first 10–15 minutes as needed.

Method	Best For	Caution
Micro-torch	All projects, especially large pours	Don’t linger—can scorch or discolor resin
Heat gun	Beginners avoiding open flames	Can create waves if too close
Tapping	Small molds and jewelry	Limited effectiveness on deep bubbles
Straw blowing	Emergency fixes or tool-free setups	Moisture contamination risk

Step-by-Step Guide to Bubble-Free Resin Pours

Follow this timeline-based approach for consistently smooth results:

1. 24 Hours Before: Bring resin and hardener to room temperature indoors. Ensure workspace is clean and dust-free.
2. 1 Hour Before: Seal porous items (wood, paper, etc.) and allow to cure fully. Prepare molds and check for debris.
3. Mixing Stage: Measure accurately using graduated cups. Stir slowly for 3 full minutes, scraping sides and bottom.
4. Let Sit: Allow mixed resin to rest for 2–3 minutes. This lets larger bubbles rise and pop naturally before pouring.
5. Pour Low and Slow: Dispense resin close to the surface in a steady stream. Avoid zigzag motions that trap air.
6. Initial Bubble Check: Immediately inspect for bubbles. Use a torch or heat gun with quick passes.
7. Monitor for 15 Minutes: Tap sides gently every few minutes to release deeper bubbles.
8. Cover and Cure: Place dome or box over piece to protect from dust. Cure in a stable environment for 24–72 hours.

Tip: If doing layered pours, wait until the first layer is tacky (not wet) before applying the next. This reduces interlayer bubbles.

Common Mistakes That Cause Persistent Bubbles

Some habits seem harmless but consistently lead to bubble issues. Watch out for these pitfalls:

• Over-mixing: Stirring too fast whips air into the mixture like beating egg whites.
• Using expired or poorly stored resin: Old resin loses its ability to self-level and degas effectively.
• Pouring too thick: Exceeding manufacturer’s recommended depth traps heat and bubbles in the center.
• Adding additives improperly: Mixing in glitter, powders, or oils after resin is poured increases viscosity and air retention.
• Rushing the process: Skipping the rest period after mixing means you pour in air-rich resin.

A real-world example illustrates this: Lisa, a hobbyist in Portland, kept getting cloudy coasters despite using a torch. She reviewed her process and realized she was mixing two different brands of resin together, thinking they were compatible. The mismatch altered the cure chemistry, increasing foam formation. After switching to a single, reputable brand and slowing her mix time, her pieces became crystal clear.

FAQ: Common Questions About Resin Bubbles

Can I sand out bubbles after the resin cures?

Yes, but only for minor surface imperfections. Lightly sand with 400-grit paper, then apply a thin second coat of resin to restore gloss. Deep bubbles may require filling and polishing, which affects clarity.

Is it normal for bubbles to appear hours after pouring?

Sometimes. If you used organic inclusions like leaves or wood, delayed bubbling can occur as trapped moisture escapes. Always pre-seal natural materials to prevent this.

Do all resins bubble equally?

No. Different formulations have varying viscosities and degassing properties. Look for resins labeled “low bubble” or “self-leveling.” Brands like ArtResin and ProMarine are known for minimal bubble formation when used correctly.

Bubble Prevention Checklist

Use this checklist before every pour to maximize clarity and minimize defects:

• ✅ Resin and hardener at room temperature
• ✅ Workspace free of drafts and dust
• ✅ Substrates sealed (if porous)
• ✅ Accurate 1:1 or manufacturer-recommended ratio
• ✅ Mixed slowly for 3+ minutes
• ✅ Mixture rested 2–3 minutes before pouring
• ✅ Poured close to the surface
• ✅ Torched or heated immediately after pour
• ✅ Tapped gently to release trapped air
• ✅ Covered during cure to block contaminants

Final Thoughts: Mastery Comes with Method

Bubbles in resin art are rarely inevitable—they’re usually signals of overlooked details in preparation or execution. With attention to temperature, mixing, sealing, and finishing techniques, you can produce smooth, professional-grade pieces that showcase your creativity, not flaws.

Every artist encounters setbacks, but each bubble teaches something valuable about process control. Instead of viewing them as failures, treat them as feedback. Adjust one variable at a time, document your results, and refine your workflow.

💬 Ready to master bubble-free resin art? Start by implementing one new tip from this guide in your next project. Share your progress, ask questions, or post your results—your journey inspires others!