Epoxy Resin Mixing Instructions
Proper mixing of the components is one of the most important steps when working with epoxy resin. Even high-quality epoxy resin may fail to cure properly if the mixing ratio is incorrect or if the components are not mixed thoroughly.
Preparation for Mixing
Before starting, prepare the following:
- Digital scale
- Clean and dry plastic or paper mixing container
- Wooden mixing stick or spatula
- Spirit level for checking surface alignment
- Personal protective equipment
All components should be at room temperature between +20°C and +25°C before mixing.
Measuring the Components
Resin (Component A) and hardener (Component B) must be measured strictly by weight in grams.
Do not measure the components in milliliters unless specifically instructed by the manufacturer.
Before starting, make sure your digital scale is set to grams (g).
Always follow the mixing ratio specified on the product label or in the instructions for your specific epoxy resin system.
Different epoxy resin systems may require different mixing ratios, such as:
- 100:55
- 100:60
- 100:66
- 100:70
- 100:92
Incorrect proportions may result in incomplete curing, a sticky surface, reduced strength, or complete failure of the project.
Mixing the Components
After accurately measuring the components, combine the resin and hardener in a single mixing container.
Mix thoroughly for 5–7 minutes.
During mixing, make sure to:
- Stir the mixture slowly
- Scrape the material from the sides of the container
- Scrape the material from the bottom of the container
- Avoid mixing too quickly to prevent excessive air bubbles
Pay special attention to the sides and bottom of the cup, as these areas often contain unmixed material.
The components must be fully combined into a uniform mixture with no streaks, swirls, or unmixed residue.
Insufficient mixing is one of the most common reasons why epoxy resin remains sticky or fails to cure completely.
Adding Dyes and Pigments
Once Components A and B have been thoroughly mixed, you may add:
- Epoxy resin dyes
- Pigment pastes
- Pearl pigments
- Metallic powders
- Special decorative additives
For best results, use only dyes and pigments specifically designed for epoxy resin.
Do not use water-based colorants, as water may interfere with the curing process and cause cloudiness or other defects.
The total amount of dyes, pigments, and other additives should not exceed 3% of the total weight of the mixed resin.
Pouring the Resin
Once mixed, the epoxy resin can be poured into:
- Silicone molds
- Prepared formwork
- Art panels
- Molds and casting forms designed for epoxy resin
Before pouring, make sure the working surface is perfectly level.
A spirit level or bubble level is recommended for checking surface alignment.
Temperature and Humidity
For best results, work under the following conditions:
- Air temperature between +20°C and +27°C
- Relative humidity no higher than 50–60%
Optimal conditions are:
- Temperature: +22°C to +25°C
- Humidity: 50–55%
High humidity may cause surface cloudiness, defects, and reduced quality of the finished piece.
It is not recommended to work with epoxy resin during rain or immediately after rainfall if the humidity in the workspace exceeds the recommended levels.
Preventing Resin Overheating
During the curing process, epoxy resin generates heat through a chemical reaction.
It is not recommended to leave more than 150 grams of mixed resin in a single container for longer than 10–15 minutes.
A large volume of mixed resin in a small container may heat up rapidly and cause:
- Overheating
- Yellowing
- Smoke formation
- Cracking
- Resin boiling
If you have prepared a large quantity of resin, it is recommended to transfer it immediately into several wider containers or pour it into the mold as quickly as possible.
Helpful Recommendations
- Use only clean and dry tools and containers
- Always follow the manufacturer's mixing ratio
- Mix thoroughly for at least 5–7 minutes
- Monitor temperature and humidity levels
- Do not exceed the recommended amount of dyes and additives
- Do not leave large volumes of mixed resin in a single cup
- Perform a small test pour before starting a large project
Following these recommendations will help you achieve proper curing, high strength, excellent transparency, and professional-quality results.