Mastering the Art of Bubble-Free Epoxy Resin: A Comprehensive Guide

If you ask any epoxy resin artist, whether they are an expert or are new at resin art, the one annoyance they will all complain about is air bubbles and trapped bubbles in resin. It happens with every epoxy project and with every epoxy brand, and there is nothing worse than noticing these trapped air bubbles once the resin has already cured.

There are many ways of getting these micro bubbles out of resin before you set it to cure, and we are here to share all of the tips and tricks of how to get bubbles out of resin so you will feel confident with your art throughout the entire process.

We will start this guide with first understanding the tiny bubbles and why they form in the first place, because how can you truly battle air bubbles in resin without knowing where they come from and why they form?

Next, we will give you tips that you can apply to the process of your resin work, and finally, we will chat with you about bubbles that appear after you apply your epoxy.

So whether you do smaller resin projects like epoxy coasters and resin jewelry in silicone molds, or you are working with a pouring resin or a thicker resin for your resin tables and river tables, we are going to give you all of the information you could possibly need for preventing bubbles in your resin.

Let's go.

1. Understanding the Culprits: Why Do Bubbles Form in Resin?

Bubbles can ruin the aesthetics of your epoxy project, but understanding where they come from and why they form is the first step in preventing bubbles.

 

Air Trapped in Resin

Air trapped right in your resin mixture is a one of the first culprits of air bubbles in your pours.

To minimize air that gets trapped in your resin and hardener, once you mix the two components together, next, stir the epoxy slowly and consistently, ensuring that you scrape the sides and bottom of the container.

This slow mixing will keep the surface tension of your epoxy a bit better, and you won't allow air the opportunity to introduce itself into the mixture at this point.

This also goes for adding colorants into your epoxy. Mix them thoroughly and slowly!

Next, Allow the mixture to sit for a few minutes before application to let any air escape that has been introduced.

 

Moisture Contamination

Moisture is another sneaky villain that can lead to bubbles, although, it is not as common.

Always work in a dry environment and store your epoxy resin in a cool, dry place. Make sure that all tools, molds, and surfaces are completely dry before starting your project. If they are wet in any way, this will lead to uneven spots in your resin where that water was trapped.

 

2. Preparing Your Resin Workspace for Bubble-Free Success

Creating an environment conducive to bubble prevention is crucial. It is best to start off on the right foot.

 

Clean and Dry Resin Tools

Ensure your tools are spotless before mixing epoxy.

Residue from previous projects can introduce impurities and air into your resin. Clean resin cups, stirring sticks, and mixing cup or containers thoroughly before starting a new project, if you are using reusable resin cups and resin tools.

 

Temperature Control of your Working Area

Maintain the optimal temperature for your epoxy working space.

Different epoxy brands have different ideal temperatures, and this is something you will need to know about before working with your brand of epoxy. At this point, have a good read of your resin brand on the back of your resin and hardener.

Follow the manufacturer's recommendations, as working in an environment that has too hot or too cold temperatures can lead to bubble formation, among other problems including curing resin.

 

Humidity Management

Control the humidity in your workspace.

High humidity is another factor that can possibly contribute to moisture-related issues. Consider using a dehumidifier in your workspace (if you live in an area prone to high humidity) as a means to prevent air bubbles.

Of course, this is only a consideration point if you live in a very humid environment - not all resin artists have a dehumidifier in their workspace.

 

3. Mixing Techniques for Bubble-Free Resin

The way you mix your epoxy will be the defining point of whether or not you have bubbles in your resin. Mixing properly will lead to fewer bubbles.

 

Hot Water Bath

You can warm your resin before using it to lower the viscosity.

This is something I have never personally done, but many resin artists swear by it. Giving your resin and hardener a bath, while still closed in the bottles, in warm water.

As your resin kit is submerged in warm water water (or water that is slightly warmer than the room you are in), it is said to make your resin have a low viscosity while it is that temperature, meaning it will flow easier.

I am not recommending this, only because it is something I have not tried personally; it just something many resin artists do.

I myself prefer to work with room temperature resin and follow the brand guidelines on the bottles. I can see how you might want a more viscous, warm resin for some really intricate molds or for a thin layer, but for resin bubbles, I prefer to follow all the other methods.

 

Gentle Stirring of Resin

Stir the resin mixture slowly and methodically.

Avoid vigorous stirring, as this can and will introduce air bubbles into the resin. Take your time and be patient during the mixing process, as it is easier to be patient and take your time, than it is to remove resin bubbles afterwards.

This is really one of the most important parts that you can play when you mix resin, as you can create bubbles easily at this stage. Be aware of this.

 

Scrape the Sides and Bottom of your Resin Containers

Ensure thorough mixing by scraping the resin container.

Resin that clings to the sides and bottom of the mixing container may not be fully blended once you pour your resin and hardener together. When you are mixing resin, scrape these areas slowly and thoroughly to incorporate all components evenly.

 

Let Your Resin and Hardener Mixture Rest

Allow the mixed epoxy in to rest before application.

Letting the mixture sit for a few minutes after stirring allows air bubbles to rise to the surface and break the surface tension to escape, and this goes for a thinner viscosity resin or a deep pour epoxy as well. This simple step can significantly reduce the number of bubbles in your cured epoxy.

 

4. Techniques for Epoxy Application to Minimize Bubbles

Applying epoxy resin requires finesse to achieve a flawless finish when it comes to resin bubbles in the finished product.

 

Puddle Pouring Method

The way to do the "puddle pouring method" is starting with a small puddle in the center and spreading your clear resin outward.

This technique of resin pouring minimizes the air bubbles trapped underneath the resin. Slowly add more resin as needed, keeping the layer thin to prevent excessive heat buildup.

 

Use a Heat Gun or Torch to Remove Bubbles

Eliminate resin bubbles on the surface with controlled heat after your pour.

Passing a heat gun or torch lightly over the resin surface helps burst any remaining bubbles. Keep the heat source moving to avoid overheating or scorching the resin. This is the most effective way of removing bubbles from your resin, especially those micro bubbles that you really can't see until you are holding your cured epoxy!

Once you use your heat gun, you will watch the surface bubbles pop by the hundreds. It is really satisfying when you remove bubbles from your resin.

Read about the best heat guns to use for epoxy

Even one air bubble that makes its way to the top will leave your work looking like it has a porous surface, and none of us want that. Not even a few bubbles will suffice. We want clarity: a glass like surface when we are finished.

Can I use a hair dryer to pop bubbles?

People will often ask if they can just use a hair dryer to remove air bubbles and new bubbles, but we do not recommend this. Resin bubbles need an actual heat gun, and they are not expensive at all. Hair dryers are not hot enough, and the heat is not concentrated enough that you can adequately control the direction of flow.

Another great tip: Use heat guns for smaller resin projects, and reserve a propane torch or a blow torch for those large resin projects like flooring or countertops, and only if you have practiced first. I find that a heat gun is great for most of the projects we do around here, and there is less chance of overheating or burning that you may get from use of a propane torch.

 

Thin Layers of Resin and Multiple Pours

Divide your project into multiple resin pours for optimal results.

Applying a thin coat at a time allows trapped air to escape from the entire surface more easily. Plan your project to include multiple pours, as this allows bubbles to escape from the surface of the resin each time, allowing each layer to partially cure before adding the next.

This process can be repeated each time to allow bubbles to come to the surface of the resin. Use your heat gun each time on the surface to pop the bubbles.

 

5. Protect Resin During Curing

One last thing you can do is to cover your resin while it is curing. This will prevent any dust or anything from landing on your epoxy before it becomes cured resin. Dust particles can leave small divots on the surface of your resin.

Some resin artists use a plastic bag to cover their work, but I prefer finding a box or better yet, a Rubbermaid container upside down over your work. You could also use a pressure pot for resin, which will speed up the curing process.

 

6. Troubleshooting: Dealing with Resin Bubbles After Application

Even with precautions, bubbles may still appear. Here's how to tackle them.

 

Popping Resin Bubbles Manually

Use a clean pin or toothpick to pop surface bubbles and a heat gun afterwards.

For resin bubbles that appear after application, gently pop them with a pin or toothpick. Be careful not to disturb the surrounding epoxy. If your resin has not cured, you can try to use a heat gun to smooth the area out afterwards.

To really get this resin bubble popping to work well, you have to catch it at the right stage of curing or it won't work. It is work the try though, as you can always sand the bubble or popped spot away afterwards.

 

Sanding and Polishing Resin

Smooth out imperfections with resin sanding and polishing.

Once the resin has fully cured, sand the surface lightly to remove any imperfections. Follow up with a polishing compound for a glossy, bubble-free finish or fish eye free surface.

 

 

Summary: Key Takeaways for Achieving Bubble-Free Resin

Great tips: To prevent bubbles in your resin is a combination of preparation, technique, and patience.

• Understand the Culprits: Identify where air or moisture (ie: in your resin mold) can be trapped as primary causes.

• Prepare Your Work Surface: Keep resin tools clean, control the temperature and humidity.

• Master Mixing Techniques: Stir gently, scrape thoroughly, and let the resin rest.

• Perfect Application: Utilize puddle pouring, heat tools, and plan for multiple layer pours.

• Troubleshoot Effectively: Pop bubbles manually and finish with sanding and polishing if necessary.

 

Frequently Asked Questions About Bubbles in Resin

Question: How can I prevent bubbles in epoxy resin?

Prevent resin bubbles and maintain a crystal clear resin by mixing slowly, scraping the container, and allowing the epoxy to rest before application. Maintain a clean, dry workspace and control temperature and humidity.

 

Question: Why do bubbles form in epoxy resin after pouring?

Bubbles can form due to air entrapment during mixing, moisture contamination, or improper application techniques. Ensure thorough mixing, a dry environment, and use appropriate pouring methods.

 

Question: Can bubbles in cured resin be fixed?

Yes, bubbles in cured epoxy can be fixed by manually popping them with a pin or toothpick. For larger imperfections, sand the surface lightly and polish for a smooth finish.

 

Question: Is it normal for bubbles to appear in epoxy resin?

It's common for resin bubbles to appear, but with proper techniques and precautions, you can minimize their occurrence. Thoroughly follow mixing and application guidelines for the best results.

 

Question: What is the ideal curing time to avoid bubbles in epoxy resin?

The ideal curing time varies by epoxy resin brands, but allowing each layer to cure before applying the next is generally recommended. Follow the manufacturer's guidelines for specific curing times.

 

Conclusion

In conclusion, achieving a bubble-free epoxy project requires a combination of understanding the factors that contribute to these bubbles, really good preparation, and careful execution of mixing and application techniques.

By following these guidelines for keeping your epoxy work bubble free, you will find you are much happier with the end results of your project and surface.

Achieving that crystal clear, glass like resin surface is what we are all going for, and knowing all of these points will get you there. And it always begins with choosing the right resin as well!

Read: How to find the right resins for specific projects

Bookmark this page and have a read through before you do any resin work, until you are super familiar with all the methods of preventing resin bubbles and know them like the back of your gloved hand!

 

Here are some more resin articles you may find interesting or worth bookmarking to read later!

 

Resin How To's

How To Write On Resin

How To Seal Paper For Resin

 

Best Resin For Your Project

Best Resin For Jewelry

Best Resin For Coasters

Best Resin For Wood Surfaces

 

USE RESIN SAFELY

No matter what type of resin you decide to use, always use personal protective equipment (PPE). Take time to carefully go over safety data sheets before making anything with resin, and make sure you have the proper gloves on (not latex) and the right respirator for resin protection.

Here are the exact gloves we always use

This is the respirator we use and recommend for resin work

 

And please remember, even if your epoxy resin of choice is "VOC-free, odor free" and/or "non toxic", please always wear the proper respirator for epoxy resin.

Read more about resin safety here

 

Here is the BEST respirator mask for epoxy resin: this Full Face Organic Vapor Respirator checks off all of the boxes for resin safety, and comes with

• free 30 day returns
• a 1 year factory warranty
• free US shipping and free shipping on international orders

Here it is:

 

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