Mixing epoxy resin and hardener involves a chemical reaction called an exothermic reaction, which generates heat when they are mixed. Volume ratios are not a reliable method, and they should be avoided as they are inaccurate. To measure the amount of resin needed, you can use a syringe and plunger. Mixing small quantities of resin is not difficult, but it is difficult to get an accurate mix when you’re using volume ratios.
Exothermic reaction causes heat generation during mixing epoxy resin and hardener
The chemical reaction that takes place during the mixing of epoxyPolymercaptan Resin and hardener generates exothermic heat. The amount of heat generated depends on the thickness of the epoxy; the thicker the epoxy, the more it will retain heat. Also, the shape of the mixing vessel plays a role. If the mixing container is plastic, it can melt and burn you. Temperature is also a factor in epoxy curing.
To avoid this problem, use a thermometer to monitor the temperature of the mixture. An epoxy resin that is too hot can result in premature or inefficient hardening. To prevent the resin from becoming overheated, try to increase the temperature gradually. If you mix the epoxy resin and hardener at the same temperature, the temperature will increase too quickly. Alternatively, you can heat the mixture using a heat lamp or foil-backed insulation. The temperature should not be more than 30 degrees Celsius. Then, add more curing agent part-by-part to prevent it from overheating.
Volume ratios are the least reliable method
When mixing resin and hardener, it is best to use a volume ratio. This method is especially problematic when mixing small amounts of resin and hardener. It is possible to have different densities, and a difference of more than 10 parts by volume will result. This method is best used if the resin and hardener are mixed by hand. Make sure to use a large, wide container.
Another method of mixing resin and hardener is to measure each component by volume. The easiest way to do this is by using a volumetric measuring device. The volumetric mixing device will show you the proportion of resin and hardener in the ratio. Then, you will be able to pour the resin and hardener into the mold, according to the marked volume in the first column.
Avoiding resin bubbles
While you’re mixing the hardener and the silicone mold, it’s important to avoid bubbles while mixing the two components. The reason for this is that resin needs a room temperature of about 70 degrees to cure properly. A space heater can provide enough warmth to cure the resin, but if your home’s heating system is not powerful enough, a heat gun will do the trick.
When mixing resin and hardener, pour the resin slowly and carefully into the mixing cup. When pouring the resin, tilt the mixing cup slightly to ensure that no air bubbles form. The hardener should be added slowly and in a 1:1 ratio. Don’t whip the mixture, as this can cause air bubbles. Once the mixture is properly mixed, pour it into the mold. Be sure to follow the manufacturer’s instructions to avoid excessive foaming.
Accurate mixing
To ensure the correct ratio of hardener and resin, you can mix them by weight. There are two methods of measuring the proportions: weight and volume. Weight ratios are the most accurate and are expressed as parts-by-weight (paw) or parts-per-hundred (pph). For example, a three-gram batch of resin with a 100:15 weight ratio needs 45 grams of hardener. Volumetric ratios are used more commonly for dispensing equipment.
When mixing resin and hardener, you must ensure that both ingredients are measured the same way. For instance, the resin should be measured into a measuring cup, and the hardener should be measured in the same container. Make sure that the measuring cup and stir stick are both dry and clean. Moisture can affect the resin, so do not use a damp or dirty mixing vessel. The same goes for the mixing equipment and the container.
Range of acceptable error
A standardized ratio of resin and hardener must be achieved every time. To do this, follow the instructions for the pump. The ratio should be pumped for two to three minutes. For beginners, it is best to estimate the required amount, and then err on the side of too much product. As the ratio varies from the recommended range, physical properties of the resin system will decrease. The range of acceptable error is listed on the Technical Data Sheet.
Conclusion
The ratio of resin to hardener is typically 10:1 by volume or weight. This ratio may vary depending on the density of the components. For example, a ten-ounce bottle of Epoxy Curing Agent will require 14.7 ounces of hardener. To ensure a proper mix, dye the resin to make sure it is completely blended. The range of acceptable error in combining the two materials should be within 5%.
