There's nothing like crafting a bubble-free resin piece that mirrors your vision. But as every artist knows, the pesky bubbles that form during resin curing can quickly turn your masterpieces into disasters. This is a common issue, especially when mixing resin with hardener, leading to a cloudy appearance far from your desired outcome.
We have extensive experience creating flawless resin finishes on our beautiful wood phone cases and are here to share our knowledge.
Why Bubbles Form
The stirring action introduces air into the blend, and bubbles in resin emerge when resin and hardener mix. Pouring resin into molds or over surfaces can also trap air, especially when dealing with porous materials such as florals and unsealed wood in resin. Molds with curves and depth can harbor more air pockets, forming bubbles.
Preventative Measures
Preventing bubbles in epoxy or resin begins long before the pour. It starts from the point of resin selection, continues with your workspace preparation, and carries through to mixing and curing under the ideal conditions.
Choose the Right Resin
A low-viscosity resin works best for bubble-free resin results. Slow-curing resin formulations allow any inadvertently introduced bubbles to rise and escape.
Prepare Your Workspace & Materials
Ensure your workspace is free of dust and debris. Seal any materials, especially porous ones, you plan on embedding or incorporating into the resin artwork. These pushes air out from the material's pores and prevents bubbles from forming. Dusting molds with powder or using surface tension-reducing additives can prevent new bubbles from forming and help existing bubbles escape more easily.
Ensure the Optimal Conditions
Maintaining an environment temperature between 75°F and 80°F (24°C to 30°C) is crucial. At this temperature, resin maintains lower viscosity, making mixing easier and less likely to trap bubbles. Warming resin before you use it makes it more fluid, lowering its viscosity and enabling the trapped air to escape.
How to Remove Bubbles
Bubbles can mar the perfection of your cured piece, but fear not. Here are detailed techniques for eliminating bubbles in your resin — before, during, or after the curing process.
Proper Mixing & Pouring Techniques
To prevent bubbles: always mix your resin and hardener slowly and deliberately to prevent bubbles. Rapid stirring introduces unwanted air, leading to bubbles. Warming resin before you use it is another technique; slightly warmed resin tends to be thinner, helping bubbles rise and escape more easily. Pouring resin slowly in thin, even layers allow air bubbles to rise to the surface and pop.
Tools for Bubble Removal
When preventive tactics aren't enough, you can tackle bubbles directly.
Heat guns & torches: These tools break the surface tension, allowing bubbles to rise and pop. Sweep the flame across the surface, avoiding direct, prolonged heat.
Use pressure pots & vacuum chambers (advanced): Vacuum-degassing resin removes air pressure around the pour, encouraging trapped air bubbles to expand and escape. A pressure pot shrinks bubbles by increasing the surrounding pressure until they're virtually invisible.
After-Pour Tips
Applying resin can sometimes result in bubbles, affecting the finish of your product. It is vital to have strategies to tackle this common issue.
Monitor for bubble formation: Allowing your mixed resin to rest for 5-10 minutes before you use it lets the bubbles rise to the surface naturally and pop, reducing the overall bubble count. Then, after pouring, give the resin approximately 10-15 minutes for residual bubbles to appear and pop.
Pop bubbles that have already formed: Pass a flame torch over the project's surface, getting close but never directly touching the epoxy. The heat helps break the surface tension, popping the bubbles. Similarly, a hot air gun is an excellent tool for removing bubbles.
Dealing With Cured Resin Bubbles
Sometimes, some persist despite your best efforts to prevent bubbles in epoxy resin. Still, eliminating bubbles in resin during the curing stage is possible.
Surface Treatments & Corrections
Large bubbles can be removed by cutting open the bubble, carefully removing the trapped air, and then filling it with fresh resin. If the surface demands more extensive correction, consider sanding and repouring.
Start with coarse-grit sandpaper and gradually move to fine-grit sandpaper to smooth the surface. Once you've achieved a uniform finish, apply a fresh resin layer to fill in the pits left by burst bubbles and add a new, glossy finish to your project.
Tips for Specific Resin Applications
Specific steps and techniques are essential for attaining exceptional outcomes when applying resin for various unique applications.
- Pour resin slowly into the molds to help avoid bubble formation, particularly for intricately designed molds.
- Use a hot air gun or propane torch on the resin to eliminate remaining bubbles or other mistakes after pouring.
- Use slow-curing resin formulations and warm the resin before use in larger projects to reduce the viscosity and enable bubbles to rise and pop more easily.
Frequently Asked Questions
How do I remove bubbles in resin without a torch?
Warm your resin and hardener. Place the resin and hardener bottles into warm water to prevent microbubble formation.
Can a hairdryer be used to remove bubbles in resin?
Yes, a hairdryer can facilitate the removal of bubbles in resin. However, a diffuser attachment is recommended to prevent additional issues caused by the heat.
What are the strategies to prevent bubble formation in resin?
Avoid pulling air down into your mix while pouring. Gently pour the resin down the sides of your mold, allowing it to flow naturally.
What is the ideal time to let resin sit before pouring?
You can apply your resin right after a 5-minute resting period or let the resin thicken for up to 25-30 minutes for doming.
Can I use a torch to remove bubbles from the epoxy?
Yes, you can use a torch to remove bubbles from epoxy. The heat from the torch facilitates the even spreading of the liquid epoxy across the surface.