Here’s the good news.
It’s completely normal for two-part resin to get hot when you mix it. A heat-producing reaction needs to happen when you combine the two liquids. This is what causes the resin to go from a liquid to a solid. But, there can be too much of a good thing, and resin that gets too hot will cure in unpredictable ways.
How will you know if your resin is too hot?
*Pot time is shorter than expected.
*The cured resin mixture cracks.
*The resin fills with bubbles and looks foamy.
*You see excessive resin shrinkage after curing. It’s pulled away from the sides of an open space (like an epoxy table) or a resin mold.
*Your resin smokes. This is really bad. If that’s happening to you RIGHT NOW, skip to this article on why resin is hot and smoking.
How does resin get too hot?
1. You mixed too much resin and hardener at once.
Resin kits have a minimum and maximum mixing amount. Too much resin and hardener mixed together produce too much heat.
2. You added something to the resin and hardener mixture to make it heat up quicker than it should.
3. Your resin and hardener components were too warm when you started crafting with them.
4. You applied too much heat with a heat gun, torch, etc., to remove bubbles.
That heat adds to the heat of the resin reaction.
How can you keep your resin from getting too hot?
Mix no more than the manufacturer’s recommended mixing maximum.
For the resins sold in the Resin Obsession store, we have that information for you in our resin buying guide.
Mix and pour several batches of resin if necessary.
If the amount of resin you need is more than the maximum mixing amount, mix and pour smaller volumes several times. But…
The heat from previous layers adds to new layers. That means if the layer you just poured is hot, that heat will transfer to the next resin layer. You may need to wait to allow the heat to escape from the first layer before pouring the next layer.
Use a slow-curing resin.
Some deep pour epoxy resins can take hours to days to cure. They generate heat more slowly and are less likely to give you problems.
Maintain a cooler-than-normal temperature in your work area.
While the low 70s F is the ideal temperature for casting resin, you may want to work in temperatures in the 60s F if you think your resin mix will get too hot.
Find something that you can use to absorb some of the resin heat.
Metal objects can be heat sinks which means they will absorb some of the resin reaction heat. Something like a metal trivet can not only hold your project but can help to absorb some of the heat.
Confused about why my resin is hot and other things when it comes to creating with epoxy?
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Unpublished Blog Posts of Resin Obsession, LLC © 2023 Resin Obsession, LLC