How to mix two-component epoxy resin?
Not sure how to mix resin? Mixing resin is easy, although there are certain principles to follow. How do you work with resin?
Two-component epoxy resin, as the name suggests, has two components: the resin, or component “A”, and the hardener, or component “B”.
Where can I find the mixing ratio for the resin?
For each resin, you can find the mixing ratio of the two components easily from three sources:
- from the product description on the website;
- from the label on the resin itself;
- from the attached technical data sheet.
The mixing ratio will always be clear and accessible. This mixing ratio is always by weight, not by volume. Therefore, we will always measure in grams, not in milliliters.
What does a ratio like 100 : 60 mean?
It’s very simple – in this ratio, you weigh 100 grams of resin (component A) and 60 grams of hardener (component B), so you end up with a total of 160 grams of mixed resin for your castings. Need more or less resin? We’ve done the calculations for you and you can find them in a clear table here, or use the printed table provided on the back of the technical data sheet included with each resin.
How do I determine how much resin I need for my mold?
To calculate resin consumption, we have prepared this resin consumption calculator.
What do I need for mixing?
For mixing resin, you will need plastic, silicone, or paper cups, spatulas, and a digital scale.
Preparing the scale
As a first step, prepare your scale. The scale must be digital and weigh with precision to the gram, as accurate weighing is the foundation of successful resin work. To protect the scale from irreversible contamination, we recommend placing it in a plastic bag that you can easily dispose of if it gets dirty. Also, make sure the scale has working batteries. Batteries always seem to run out exactly when you least expect it, and hitting the precise ratio is nearly impossible without a scale.
Mixing resin procedure
• Place the mixing cup on the prepared scale and zero the scale.
• Weigh the required amount of component A and B and start mixing.
• Always mix resin slowly and thoroughly, scraping the sides, wiping the spatula, and mixing from the bottom. Alternate the mixing direction clockwise and counterclockwise to ensure complete blending of both components. Mix both components in the mixing cup for about 3 minutes.
• Pour the mixed material into a new cup and mix again thoroughly. Why mix again? There is almost always a spot on the walls or bottom of the cup that is not well mixed, and any poorly mixed resin will never cure properly.
What should I watch out for when mixing?
• Mixing containers must always be dry and clean; do not forget this. Never allow water to be present in the cup during mixing.
• Mix slowly with smooth movements and do not lift the spatula too high to avoid incorporating air bubbles.
What is the minimum amount of mixed resin?
Mix at least 50 grams of material. If you mix, for example, only 10 grams of resin and 3 grams of hardener, you might weigh a few tenths of a gram less, and such a small amount of material has a high percentage of inaccuracy. While such small inaccuracies are critical for small amounts, for around 50 grams of material, it is a negligible deviation that does not affect the curing process.
When can I color the resin?
Add colorants or pigments only after thoroughly mixing both components. Never add them to the resin before mixing the components, and the same goes for glitters and other decorations.
How quickly must I process the resin?
Never leave resin in the cup for too long; after mixing, a chemical reaction begins, causing the resin to start curing. If the resin is in the column it is intended for, the reaction proceeds in a controlled manner. If it is in a higher column than intended, the reaction speeds up, which can lead to rapid curing of the resin, as discussed in the article on exothermic reactions.
When can I pour the resin into the mold?
Pour the resin into molds immediately after mixing and coloring. It is important not only because the resin is usually in a higher column than intended, but also because of the working time specific to each resin. To achieve a perfect result without mishaps, pour the resin into the mold immediately.
What if I mix too much resin?
For each casting, we recommend having not only the mold you are working with but also another smaller mold for the leftover resin. If you mix a bit too much resin, it would be a shame for the excess to harden in the cup. Instead, you can create many beautiful items from the leftovers. Choose a silicone mold directly from our range.
Video guide on mixing resin