Each epoxy resin has two parts - resin and hardener. Both are later mixed to make an appropriate solution for multiple purposes. Users should have a clear idea about the mixing procedure, as one cannot expect the best result without a perfect mix at the right ratio. Procedural errors, including imperfect ratio and mistiming, can sometimes create user safety risks or damage the object where you apply the solution. It is, therefore, essential to know how to mix epoxy resin accurately. In this writeup, we shall try to show you some techniques and a few basics of measurement and mixing.
Resin and Hardener - What’s the Chemistry?
Resin is a liquid compound that can be collected naturally (especially from plants) or made artificially. But here we are basically defining the later one. It is produced as synthetic inducing cross-linking (well-controlled by formula) between particular substances. Resins come up with a capacity to get hardened under certain environments or circumstances. But what causes the circumstances, turning the resin into hard from the liquid?
Hardener plays the role here unless it is a UV resin, where the resin is exposed to UV light for hardening. In the two-part system, hardener (when added to resin) creates a long chain of molecules by binding the resin molecules together. The synthetic resin starts to get hardened and build a form within a certain time. Now come to point - what is the hardener? It is a catalyst or reactant that occurs a chemical reaction in resin when mixed.
They play two different ways -
i. by increasing mixture resilience, or
ii. by working a curing component.
Resin and Hardener Mixing Ratio
It is mandatory to know the right mixing ratio of resin and hardener, as you can not achieve the desired result otherwise. Typically, the Two-Part system follows two mixing ratios - 1:1 or 2:1. But, this is not uncommon to go beyond these two, and you even sometimes may find some more complicated ratios, for instance, 100:47, based on the purpose of using epoxy resin. However, Whatever the purpose, the mixing ratio should be as specific as possible based on that particular objective. Otherwise, you will get a substandard output, which will either be very fragile or imperfect anyway.
How to Measure and Mix Resin and Hardener?
Just as it is vital to determine the ratio before mixing epoxy, it is essential to ensure the correct measurement. There are two ways you can do this - i.e. by weight, or ii. by volume. Both methods are different, but we have decided to explain the easiest way - by weight.
Based on Weight
Weight has always been a common method of measuring epoxy and hardener before mixing them. But how is it actually done? Simply by following the below-stated steps:
- Take a digital scale and select the unit of measurement - this could be ounces or grams, as most scales come with any of the two units. Make sure you can even measure 0.01 gram or ounce (most scales also do come with this lower unit measurement feature). If you do not follow the low-unit measurement, it will be tough to get an accurate mixture.
- Suppose, you need a total of 30 ounces mixture, mixed at a ratio of 2:1 (resin : hardener). Take a cup or bucket according to the approximate amount of mixture you will require in total (30 ounces here). Place the cup or bucket over the scale and reset it to zero. You will have to press either the Zero or Tare button on the scale to reset the scale.
- Take the bottle of epoxy and pour the resin into the cup. Check if it is a total of 20-ounce resin measured. And, then pour the measured epoxy into a container where you shall mix it a while later with hardener.
- Clean the cup completely, take the bottle of hardener and pour the hardener into it. Similarly, check if it is 10-ounce accurately, as it should be 1 unit compared to the 2-unit resin.
- If you did not fix the approximate amount of total mixture earlier, rather just wanted to do it randomly, you may then take any amount of resin measured (for instance, 13 ounces). According to the 2:1 formula, now you have to count how much it should be the amount of hardener, and half of a 13-ounce (2:1 ratio) should be 6.5 ounces.
- Now it’s time to mix. Pour the measured hardener entirely into the container where you have poured measured epoxy earlier. And use a long-hand spoon or stainless steel stick to thoroughly mix the poured resin and hardener for 2 or 3 minutes. Scrap all the sides, corners, and bottom of the container more than a couple of times. It will prevent imperfect curing, particularly bubbles. If the amount is quite large, you may require to mix for some minutes.
- When you are done with mixing, start pouring immediately for the purpose you are mixing them. The longer you delay, the more effect it will lose.
Some Essential Tips
Measuring or mixing is not the only task when you think of mixing epoxy resin. There are some other facts to observe, and they are essential. We have some about those.
- Always check the temperature - both the room and the mixture. The room temperature should be between 75-degree and 85-degree Fahrenheit, where 77-degree is the most ideal. No way, you should allow the heat of mixture going beyond 95-degree Fahrenheit, where 92/93 degrees is the accurate temperature that you should expect while mixing.
- Hardener should not be exposed often in an environment that has more than 65% air humidity. When you mix the epoxy with hardener, the room humidity should no way be more than 70%.
- Epoxy and water are not compatible. So, avoid water in any condition as a catalyst! When you add color to epoxy while mixing, you should consider that watercolor is not the right color agent for it.
Remember, epoxy resin and hardener both have different densities, where epoxy is a bit weighty compared to the hardener. So, measuring by weight is more accurate than measuring by volume. But if you pour slightly more or less than your weight, don’t worry! As long as you keep the margin or error by 5%, it is good to go.