Resin So Thick

Why Is My Resin So Thick? Understanding 3 Common Causes

May 10, 2024

Are you frustrated with your epoxy projects turning out thick and syrupy? Understanding the causes of thick resin is crucial in preventing and troubleshooting these issues effectively. Thick resin can negatively impact the final outcome of your project, leading to uneven coatings, difficulty in spreading the resin, and longer curing times. It can also affect the self-levelling properties of the resin, resulting in an unsatisfactory finish. Therefore, it's essential to grasp the causes behind this issue to achieve successful results.

Consider joining a resin art workshop where you can gain hands-on experience working with resin in different conditions. In this blog, we will get into three common reasons why your resin might be thicker than desired. By exploring these factors, you will gain valuable insights into why your resin may be thick and how to prevent or fix this issue effectively. So, let's get right in!

1. Resin Viscosity: A Key Factor in Consistency

Resin viscosity refers to the thickness or resistance to flow of the epoxy resin. It is a significant factor in determining the workability and final outcome of resin projects.

  • High viscosity results in shorter working time and pot time, leading to a thicker consistency as the resin begins to cure.
  • On the other hand, low viscosity allows the resin to flow more freely, creating a fluid-like mixture that tends to level out and spread quickly.

Understanding resin viscosity is essential for achieving the desired results in epoxy projects. By manipulating the viscosity, artists can control the flow and levelling of the resin, ensuring a smooth application and curing process. Additionally, different viscosities are suitable for various techniques such as coating, pouring, or embedding objects.

In summary, resin viscosity directly impacts the handling characteristics and curing behaviour of epoxy resin. Artists must consider viscosity when selecting a resin for a specific project and adapt their techniques accordingly to achieve optimal results.

2. Different Types of Resin and Their Characteristics

When working with epoxy resin, it's important to know the various types available and their specific qualities. This knowledge will help you prevent and address problems related to resin becoming too thick. Two types of resin that tend to thicken more are Doming Resin and Casting Resin.

Doming Resin

Doming Resin is typically used to coat surfaces like artwork or tabletops. It has a unique feature known as self-levelling, which means it can spread out smoothly and create a glossy, glass-like finish. However, this self-levelling property also makes Doming Resin thicker compared to other resins. The thicker consistency ensures that it stays in place while settling down, preventing any excess from spilling over the edges.

Casting Resin

Casting resin is commonly used to make moulds and produce complex replicas. Its higher viscosity is intentional, as it helps capture fine details and prevents air bubbles from forming during the casting process. However, this higher viscosity can become problematic if not handled properly. Pouring too much Casting Resin into a mould at once can make it thick and hard to manage.

Understanding the unique characteristics of Doming Resin and Casting Resin is crucial because it allows artists to select the most suitable type for their specific needs:

  • For coating surfaces where a smooth finish is desired, Doming Resin's thickness and self-levelling nature make it an ideal choice.
  • When working on moulds or replicas that require precise detailing, Casting Resin's higher viscosity ensures accurate replication.

3. The Role of Temperature in Resin Thickness

Resin thickness is influenced not only by its chemical composition but also by the temperature at which it is stored and used. It's important to understand how temperature affects resin viscosity to ensure that your epoxy projects turn out just right.

Cold Temperatures and Increased Viscosity

When resin gets cold, it becomes thicker and harder to work with. This happens because the molecules in the resin slow down when it's cold, causing it to become more viscous. Pouring, spreading, and levelling the resin can become quite tricky in these conditions. To prevent resin from thickening too much in cold temperatures, here are a couple of things you can do:

  • Before you start using the resin, try warming it up a bit. You can place the resin container in a bowl of warm water or use a heat gun on a low level to gently heat it. This will help reduce the viscosity of the resin and make it easier to mix and work with.
  • Make sure that the area where you're working is warm enough while the resin is curing. Cold temperatures can prolong the curing time and may result in an uneven or incomplete cure, which can ruin your project.

Effects of Heat on Resin Consistency

While cold temperatures make resin thicker, excessive heat can have the opposite effect and make it thinner. This can cause its own set of problems when working with epoxy. Here are a couple of things to keep in mind regarding heat and resin thickness:

  1. When it's warm, resin tends to have a lower viscosity, which means it's more runny. This can lead to faster curing times and less time for you to work with the resin before it starts to harden. It's important to be efficient in your work when in a warm environment to avoid any issues.
  2. Applying too much heat while the resin is curing can cause it to thicken or even form clumps. This is because excessive heat can make solvents or moisture within the resin evaporate too quickly. It's best to let the resin cure at room temperature or follow the manufacturer's instructions regarding heat application.

By understanding how temperature affects resin viscosity, you can take the necessary steps to control the thickness of your epoxy projects. Whether it's pre-warming the resin in cold conditions or being cautious with heat during curing, temperature monitoring plays a huge role in achieving optimal results.


Following the best practices and implementing proper techniques, you can prevent and fix thick epoxy resin issues, ensuring successful outcomes for your projects. Remember to adjust your working methods based on the specific type of resin you are using and the temperature conditions in your workspace. Understanding the causes of thick epoxy resin is crucial for achieving desired outcomes in your projects.

By being aware of resin viscosity and its impact on consistency, you can control the flow and curing process of epoxy more effectively. With proper knowledge and techniques, you can overcome thick resin issues and create stunning epoxy projects with ease. If you're interested in learning more about resin arts and crafts, Contact Us on Arts Shala for workshops and resources that will further enhance your skills.
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