You just made something gorgeous with resin. Like you’re already dreaming about showing it off. Or selling it in your Etsy store. Or maybe, this one is good enough to keep for yourself. Then, you check on it later and immediately start screaming. Your resin now looks like a windshield your ex hit with a baseball bat. What’s going on? Your resin is cracking.
Why does resin cracking happen?
Cracking happens when resin gets too hot and cools off quickly.
Why does resin get hot?
Two-part resins include a part A (resin) and part B (hardener). When you combine the liquids, the resin mixture heats up and hardens into a solid mass. While a little bit of heat is necessary, too much heat can cause resin cracking.
How do you fix resin cracking?
Step 1: Wait for the resin to cure and completely cool.
Step 2: Sand the resin down to the level of the crack.
You can also cut out the area of the damage and refill it with resin, but you will see a seam line.
What if you don’t fix the resin cracks?
If there is only a crack or two, and you don’t mind the look, you can leave the resin cracking as is. Most people won’t notice.
If there are many cracks, or if you’re worried the piece’s structural integrity is compromised, then scrap your resin project and start over. You don’t want anyone to use what you’ve made with resin, only to have the piece fail later.
How can you prevent resin cracking?
Controlling resin cracking means controlling the heat of the resin reaction. To do that, there are three things you need to pay attention to:
1. Don’t mix too much resin and hardener at once.
Resin kits have a maximum mixing amount. This is the maximum amount of resin and hardener you should mix together in one cup at a time. Mix more than this, and the resin will overheat and crack.
⭐️ BONUS: Get the maximum mixing amount for the resins sold in the Resin Obsession store in our resin buying guide.
2. Don’t pour too thick.
The thicker you pour resin layers, the more heat builds in the resin mass. If you need to pour in thick layers, use a resin designed for that purpose. The Resin Obsession deep pour epoxy resin cures slowly, allowing heat to build gradually. You can pour it up to two inches thick at once. That makes it ideal for epoxy river tables and memorial flower paperweights.
3. Cool the resin.
While it seems a little odd to say this, cooling resin may be necessary during the curing phase. You can do this by elevating the mold surface and allowing cool air to circulate underneath. You can also lower your room temperature.
⭐️ BONUS: Get more helpful hints in this article about making an epoxy table.
You should always prepare for epoxy resin cracking.
Worst case scenario–your resin may get hot enough to smoke or catch your container on fire.
I know because I’ve done it. You can see what happened when my epoxy resin overheated and cracked.
Hate making resin mistakes?
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Unpublished Blog Posts of Resin Obsession, LLC © 2023 Resin Obsession, LLC