Liquid Glass
Over the past few years, liquid glass, better known as epoxy resin, has become one of the most popular materials in the creative world. From artwork and jewellery to river tables, decorative objects and silicone moulds, epoxy resin offers creative possibilities that few other materials can match.
Although it is often referred to as “liquid glass,” it is not actually glass. The name comes from its appearance after curing, when it forms a crystal-clear, smooth and highly glossy surface that closely resembles real glass.
If you’re new to working with resin, it’s perfectly normal to have questions such as:
- What exactly is epoxy resin?
- How does it cure?
- Why does it need to be mixed with a hardener?
- What do mixing ratios like 1:1 or 2:1 mean?
- Why do bubbles appear?
- Why do some resins turn yellow over time?
In this guide, we’ll answer these questions in clear, straightforward language, without unnecessary technical jargon.
What Is Liquid Glass (Epoxy Resin)?
Epoxy resin is a two-part thermosetting polymer.
In simple terms, it consists of two separate liquid components that remain stable while stored in their containers.
These components are:
- Resin (Part A) – the clear base resin.
- Hardener (Part B) – the curing agent that initiates the chemical reaction.
Neither component can harden on its own. Curing begins only when they are mixed together in the correct ratio.
The result is a strong, durable, transparent and glossy solid material.
Why Are Two Components Needed?
Many people believe that the hardener simply acts as a catalyst or speeds up the drying process.
In reality, that’s not how epoxy resin works.
Both the resin and the hardener become part of the final material. When mixed together, their molecules react and gradually form a three-dimensional molecular network that transforms the liquid mixture into a hard, solid plastic.
This is why accurate mixing ratios are essential.
Adding extra hardener does not make epoxy cure faster. Instead, an incorrect ratio may result in:
- a sticky surface
- a soft or rubbery finish
- loss of clarity
- reduced mechanical strength
- cracking
- incomplete curing
How Does Epoxy Resin Cure?
Unlike acrylic paints, which dry mainly because water evaporates, epoxy resin does not dry by evaporation.
Instead, it cures through a chemical reaction known as polymerisation.
This means that almost all of the mixed material remains inside the finished piece. Very little material is lost during curing.
As a result, epoxy resin offers:
- very low shrinkage
- excellent optical clarity
- high mechanical strength
- strong adhesion to a wide range of materials
What Do Mixing Ratios Like 1:1 or 2:1 Mean?
This is one of the most common questions beginners ask.
Every epoxy resin system is formulated to work with a specific mixing ratio determined by the manufacturer.
Some of the most common ratios include:
- 1:1
- 2:1
- 3:1
- 100:45
- 100:30
- 100:50
These ratios may refer to either:
- Volume
or - Weight
Understanding the difference is extremely important.
For example, one resin may require:
2 parts resin + 1 part hardener by volume
while the same product may specify:
100 parts resin + 42 parts hardener by weight.
Although these numbers appear different, both are correct, because the resin and hardener have different densities.
Should I Use a Digital Scale?
That depends on the manufacturer’s instructions.
If the ratio is specified by weight, a digital precision scale is strongly recommended.
If the ratio is specified by volume, graduated mixing cups can be used instead.
In every case:
Always follow the instructions provided for the specific resin you are using rather than relying on general rules or advice from other products.
Can I Add More Hardener to Make It Cure Faster?
No.
This is probably the most common misconception about epoxy resin.
Unlike some other materials, epoxy resin does not cure faster by adding extra hardener.
Doing so is much more likely to cause problems than improve curing.
Possible results include:
- incomplete polymerisation
- a permanently sticky surface
- increased brittleness
- reduced transparency
- significantly lower strength
What Is Pot Life (Working Time)?
Once the resin and hardener have been mixed together, the chemical reaction begins immediately.
The period during which the mixed resin remains easy to work with is known as the Pot Life or Working Time.
Depending on the product, this can range from:
- 15 minutes
- 30 minutes
- 45 minutes
- 60 minutes
- up to 2 hours or more
As time passes, the resin gradually becomes thicker and more viscous until it can no longer be poured or manipulated properly.
It’s important to remember that Pot Life does not indicate how long the resin takes to fully cure—it only refers to the time you have available to work with it.
What Is Curing Time?
Curing Time is the period required for the epoxy resin to fully harden and develop its final mechanical properties.
It should not be confused with the Working Time.
Depending on the resin formulation, full curing may take:
- 12 hours
- 24 hours
- 48 hours
- 72 hours
- or even longer, depending on the product and the ambient temperature.
A project may feel dry to the touch after only one day, but it often requires several more days to reach its maximum hardness, strength and chemical resistance.
For this reason, it’s always best to avoid sanding, polishing or putting the piece into service until the manufacturer recommends.
Why Does Epoxy Resin Get Hot?
During curing, epoxy resin naturally produces heat.
This process is called an exothermic reaction.
The larger the volume of mixed resin left inside a container, the more heat it generates.
Excessive heat buildup can lead to:
- overheating
- very rapid curing
- yellowing
- cracking
- warping
- and, in extreme cases, smoke or melting of the mixing container
This is why manufacturers specify a maximum recommended casting depth for each resin system. Exceeding that limit can cause excessive heat generation and negatively affect the final result.
The 5 Most Common Causes of Failure
Most unsuccessful resin projects are not caused by defective materials, but by mistakes made during mixing or application.
Here are the most common ones:
1. Incorrect Mixing Ratio
This is by far the most common cause of sticky or improperly cured resin.
Even small deviations from the recommended ratio can prevent the chemical reaction from completing correctly.
2. Inadequate Mixing
If the resin and hardener are not mixed thoroughly, some areas may never cure properly.
Always scrape the sides and bottom of the mixing cup while stirring to ensure both components are evenly blended.
3. Low Temperature
Most epoxy resins perform best at around 20–25°C (68–77°F).
At lower temperatures:
- the resin becomes thicker,
- bubbles escape less easily,
- the chemical reaction slows down,
- and curing may take considerably longer.
Some resins may even remain soft or tacky if used below the manufacturer’s recommended temperature range.
4. Moisture
Excessive humidity can affect certain epoxy systems, causing surface imperfections such as:
- cloudiness
- a greasy or waxy surface (amine blush)
- poor surface finish
Whenever possible, work in a clean, dry and well-ventilated environment.
5. Rushing the Process
One of the most common beginner mistakes is handling or moving the project before it has fully cured.
Doing so may result in:
- fingerprints,
- dents,
- surface marks,
- distortion,
- or permanent imperfections.
Patience is often the difference between an average result and a professional-looking finish.
How to Prevent Bubbles in Epoxy Resin
Air bubbles are one of the most common challenges when working with epoxy resin, especially for beginners. They may form while mixing the resin and hardener, escape from porous materials such as wood, or become trapped around decorative elements like dried flowers, shells, stones or other inclusions.
Fortunately, in most cases they can be greatly reduced—or even eliminated—by following a few simple best practices.
Tips for Minimising Air Bubbles
- Mix slowly and steadily. Vigorous or fast stirring introduces unnecessary air into the resin, creating more bubbles that are difficult to remove later.
- Work at room temperature (20–25°C / 68–77°F). Slightly warmer resin is less viscous, allowing trapped air bubbles to rise to the surface more easily.
- Let the mixed resin rest for a few minutes before pouring. This gives some of the trapped air time to escape naturally.
- Seal porous surfaces first. Materials such as wood, MDF and dried plants contain tiny air pockets that release bubbles into the resin. Applying a thin sealing coat before the main pour can significantly reduce this problem.
- Use a heat gun or small butane torch carefully, following the resin manufacturer’s recommendations. Gentle heat lowers the resin’s surface tension, allowing small bubbles to rise and pop. Avoid holding the heat in one place for too long, as excessive heat may cause overheating, ripples, or premature yellowing.
- Avoid stirring the resin after it has been poured. Doing so introduces new air bubbles that are much harder to remove.
Tip: A few tiny bubbles immediately after mixing are completely normal. With proper preparation, careful mixing and the right working temperature, most bubbles will either rise to the surface on their own or can be easily removed before the resin begins to cure.
Conclusion
Epoxy resin is an incredibly versatile material that can transform simple ideas into stunning creations when used correctly. Although it may seem intimidating at first, the basic principles are straightforward: measure accurately, mix thoroughly, work at the proper temperature and allow sufficient time for the resin to fully cure.
Most of the issues beginners encounter—such as sticky surfaces, trapped bubbles or incomplete curing—are not caused by the resin itself, but by small mistakes during preparation or application. With a little practice and by carefully following the manufacturer’s instructions, you can consistently achieve clear, durable and professional-looking results.
Choosing the right resin for your specific project, using quality materials and following essential safety precautions—such as wearing nitrile gloves and working in a well-ventilated area—will greatly improve both your results and your overall experience.
Whether you’re creating jewellery, decorative objects, artwork, tabletops or woodworking projects, epoxy resin offers almost unlimited creative possibilities. With the right knowledge and a little patience, you’ll soon be able to make the most of this remarkable material and enjoy the creative process with confidence.
Related Products
To get started with epoxy resin, you’ll need a few essential materials: