The Process Of Cooling Down Epoxy Resin
As the epoxy resin curing process gets underway, there is a chemical reaction that takes place between a resin and a hardener, generating heat. There are a few things that can go wrong here. For example, if the cool, initial temperature of the container rapidly increases to a high heat, it will likely lead to the epoxy cracking and bubbling.
In this article, the Just Resin team will explore what can occur if your resin overheats or heats too quickly and some methods on how to cool down resin.
Possible Accidents from Uncontrolled Resin Heat
Curing epoxy resin too fast
Resin reactions heavily rely on mass. As such, the more you mix, the more heat is produced. When you mix larger portions, excessive heat builds upon itself, and your mixture can heat quicker than expected —making your resin harden before you can even pour it into your mould or coat.
The cured resin breaks
The mixture starts to cool as soon as the resin mixture has solidified, marking the end of the first stage of curing. When the mixture is heating too quickly, so, too, will the rate of the cooling. The quick cooling temperature won’t allow the resin to move yet, subsequently cracking to release tension.
The exothermic reaction
It’s possible, especially when the resin gets too hot. Also, mixing it in cups that are not heat-resistant can cause the container to melt, and if the material itself or anything in contact is flammable, it could ignite a fire.
It is best to always have safety equipment on hand as a safety precaution if your resin overheats or starts smoking.
How Can I Cool Down Resin?
Prevention is better than remedy, so temperature management is key to a successful finish. First, practice prevention by taking steps to avoid overheating:
● Don’t mix more than the maximum amount recommended by the manufacturer
● Try to keep your work area cooler than normal, with air conditioning if possible.
● Check if your resin components are warm (not hot) before mixing them.
● Split the epoxy mixture into smaller containers to allow the heat to dissipate, allowing more working time.
With more experience, you may be able to anticipate the risk of overheating, especially when working with larger volumes.
Some common resin projects that require these thick, deeper pours are resin river tables, dense sculptures, giant paperweights, and similar deep-pour artworks. We recommend using slow-curing, deep-pouring epoxy casting resin, which will allow gradual heating of the formula for days rather than mere hours.
If you have taken these precautions but still notice your resin project is generating too much heat, you can proceed to:
Raise the resin surface
This method allows air to circulate on all sides of the mould or surface. Heat can then escape much easier, reducing the risks of cracking.
Fan the surface
Once the surface is settled, push air away from your resin with a fan. Think of it as blowing your breath over food when it's too hot. As the air blows the heat away, the resin retains its cool.
Assign a cooling surface for your resin
If you feel like your resin is heating too fast, you might want to put the mixture container in a cooler environment, such as a water bath. However, be extra careful as the resin will not cure if excess liquid or moisture is added.
Learn More on Resin Art from Our In-House Experts
Curing Epoxy Resin FAQS
What should I do if the resin overheats?
Once you see bubbles or smoke, your resin is beginning to overheat. Pour the mixture into a metal mould, ideally with a thin layer, to stall the exotherm.
Never throw hot resin away, as the reaction can melt your rubbish bin, or worse, start a fire with some of the other items surrounding it. Instead, wait for it to cool before disposal.
How much time does resin take to cool?
Resin usually takes between 24-72 hours for the cooling process to finish. You mustn’t touch or move the piece during this period to avoid damaging the surface.
Is it possible for the resin to cure in hot weather?
Resin will actually cure best in warm temperatures, unless it is a humid climate. Like prolonged heat exposure, these moist conditions affect the curing process, and can contribute to a cloudy blush and lacklustre finish.
We recommend working with two-part epoxy resin in a warm, dry environment during the curing phase for optimal results.
What temperature does the curing process require?
The ideal temperature for curing is 22-25°C. We recommend 50% humidity, but anything below 80% works as well. Again, craft resin cures best under warm and dry conditions.
Why does resin melt?
The thermosetting polymer chain starts disintegrating when you apply heat to your resin. The resin softens as the breakdown occurs. You might see it as melting, but what’s really happening is chemical disintegration.
Can I over-torch my resin?
Yes, this is possible, which is why we don’t recommend holding your torch too close in one spot for too long or too close to the resin surface. Doing so can cause dimples or ripples in the surface, or even burn the resin itself.
Is it possible for the resin to catch fire?
Extreme temperatures might make some epoxy resins catch fire, which is one of the reasons why it requires special handling. We recommend operating in a dust-free, well-ventilated area.