How to Measure And Mix Epoxy & Hardener

Ready to make your arts, crafts, and handmade goods shine with a resin topcoat? Epoxy resin and hardener add a crystal-clear and high-gloss shine that protects, enhances, and completes your artistry. Clear coatings are popular, but they are far from your only option. Mix in a color or use a mold to create the illusion of stone, metal, and more. You can also use resin to create castings for your signature works of art.

Step 1 Determine How Much Epoxy Is Required

Epoxy resin is created by mixing a 1:1 ratio of epoxy and hardener. Once evenly mixed, a chemical reaction is created that transforms the compounds from a liquid to a thick and sticky gel. The gel remains flexible for approximately 45 minutes after being mixed. Then it begins to cure. Once complete, it is a high-gloss solid.

Before you begin mixing, you must determine how much resin you require. You don’t want to mix too much and be wasteful, but you don’t want to mix too little and be left scrambling to mix more before it begins to cure. This Resin Calculator will help you estimate how much resin you will need for your project. Unlike most resin calculators, this calculator:

• Calculates both square and cylindrical projects.
• Factors in how thick you want your resin to be.
• Provides tips for calculating irregular shapes.

We always suggest mixing a bit more just in case you make an error in application or if inspiration takes hold and you need more.

Step 2 Prep Your Workspace

An important aspect of learning how to mix your resin is prepping your workspace. The tips below ensure your workspace is safe, organized, and conducive for mixing and pouring.

• Ensure your workspace is well ventilated. Ideally, close to an open window that won’t disrupt your work if the wind blows.
• Resin mixes best if the temperature in your home or art studio is between 75 to 85 Fahrenheit or 24 to 30 Celsius, with humidity of less than 50%, but never more than 80%.
• If your workspace temperature or resin and hardener bottle temperatures are below 75 to 85 Fahrenheit or 24 to 30 Celsius, it will be too thick to work with. It will also have too many bubbles to smooth or torch out.
• If your workspace temperature or resin and hardener bottle temperatures are above 75 to 85 Fahrenheit or 24 to 30 Celsius, they will begin to cure rapidly giving you significantly less than 45 minutes to work with.
• To warm up cold bottles, place them in warm (not hot) water for 15 minutes. Wipe off all water on the exterior of each bottle before measuring. Even a tinydrop of water will leave your resin cloudy when it cures. *Warming in water will shorten your working time from 45 minutes to 35 minutes.
• To cool off your workspace or bottles, turn on the air conditioning, or wait for a cooler time of day to measure and mix.
• Resin is sticky, but it won’t stick to plastic, so line your workspace with plastic trash bags, a vinyl shower curtain, or a plastic drop sheet, and secure it in place with painter’s tape.
• Use a level to confirm your table or workspace is flat to ensure even curing.
• Lay out or prop up your art. Again, use plastic items to prop things up, such as a plastic easel or plastic blocks.
• Wear disposable gloves to protect your hands. To minimize irritation, wash your hands or arms immediatelywith soap and water if the mixture comes in contact with your skin.
• Gather your supplies including: plastic measuring cups, plastic mixing stick and spreader, disposable brush, toothpicks to remove dust or hair, timer (your smartphone works), craft torch, cardboard or plastic boxes to cover your work while it cures, plastic molds, plastic tweezers, and anything you need to complete your project.

Step 3: Measure and Mix

Now that your workspace is prepared, it’s time to measure your resin and hardener to an equal 1:1 ratio. To answer one of the most common questions, no—you cannot speed up the curing process by adding more hardener.  

Ensure you have ample time to measure and mix without disruption, as time is of the essence. Keep your pets out of the room so that no fur floats into your mixture.

1. Put on your gloves.
2. Carefully pour equal parts of resin and hardener into your plastic measuring cup or into a larger plastic container. A measuring cup is ideal as it makes pouring easier. *Be sure to place the correct cap on each of your bottles, or they may begin to cure in their bottles.
3. Set your timer for 3 minutes.
4. Mix thoroughly, scraping the sides and bottom of your plastic cup or container as you mix, in a manner similar to mixing cake batter. Without thorough mixing, you will have soft spots that won’t cure evenly or properly.
5. Set your timer for 45 minutes, or 35 minutes if you warmed your bottles in water or if your bottles or workspace is warmer than advised. *Or set your timer for 5 or 10 minutes less so that you are aware of when time is running out.
6. Pour and spread to your desired thickness, then torch to remove bubbles.
7. Place your cardboard box or plastic container over your art to protect it while it cures.
8. After 24 hours your resin will be cured to touch, but not fully cured. Full cure time is typically 72 hours. Resin that is more than 1/2 an inch thick can take up to 7 days to cure.