Why does epoxy bend when hot? What is this "tempering" anyway? And what really helps to prevent resin from bending?
Hello dear DIY resin wizards and crafters! You've probably experienced this before: You're busily pouring and designing with epoxy resin, and suddenly - poof! - your masterpiece warps like a melted snowman. Don't worry, it's not witchcraft! In this blog post, we'll dive into the crazy world of epoxy deformations when exposed to heat and reveal a few magic tricks to prevent such melting mishaps.
Resin, hardener, action! Why epoxy bends with heat
Picture this: Your fresh work of epoxy art has just stepped into the spotlight, when suddenly the sun is beating down hot or the hair straightener in the next room is having a temperature party. What's actually happening? Well, dear DIY artists, it's because of the small molecules in the epoxy resin that really party when it's hot. They start dancing and wiggling, and there goes the stability of your creation.
Here comes the heat protection trick:
1. the right dance partner: resin choice is king!
Before you dive into the resin fun, see if your epoxy can withstand a hot flirtation with temperatures. There are heat-resistant types out there that will stay cool in the scorching sun. Resins with a 2:1 blend like COLOREBRRY's BERRY RESIN, which is heat resistant up to 95°C, are best. However, even here the resin can bend in the aftermath of heat - just not as bad as a resin with a 1:1 mix ratio.
2 Mix it, baby, mix it!
Remember, finding the right mix is like finding the perfect dance step - it makes all the difference! Use the recommended mix ratio of resin to hardener to give your artwork the sturdy hold it deserves. This is the only way for the molecules to bond in the right ratio and ensure the performance of the resin. So it's imperative that you stick to the mixing ratio given and don't experiment like one of my customers, for example, who thought, "More hardener in the mix means harder end result!" Unfortunately, that backfired. Also, take your time and make sure you have mixed the resin and hardener 100% correctly. There should be no streaks left in the resin mix - only then can you continue to use it for casting.
3. wait for hardening
Please allow the epoxy to cure completely. Even if you can remove the epoxy from the mold ahead of time because it appears the dance is over, each resin is still curing. Curing inside the resin cast is not yet complete. Only after 3-4 weeks your resin artwork is really hardened and only then you can further process it to an etagere. This also applies to artwork for the wall. Please do not ship any of your artwork immediately after completion. If you wrap it in bubble wrap for safe shipping, this very protective wrap can leave marks.... So again, wait 3-4 weeks.
4. hot cooling! Remember to cast your artwork in optimal conditions. Room temperature and / or humidity directly affect curing. Not a hot disco exit, but an elegant exit! By this I mean that the curing process should be done at the recommended temperature. Excessive temperatures/high humidity during cure can cause uneven cross-linking of the molecules and affect the structure of the resin. This also promotes the likelihood of faster bending / deformation downstream.
So what is actually tempering and how is it supposed to help resin bend less?
Epoxy tempering, also referred to as "post-curing", is a process in which the fully cured resin is subjected to a controlled heat treatment. This step is not always necessary, but there are certain reasons why epoxy post-curing may be useful in some cases.
So, by tempering, we mean a controlled and constant addition of heat for a specified time. This tempering can improve the mechanical properties of the cured resin, including its strength, hardness and toughness. The additional heat treatment can relieve any internal stresses that may be present in the material, resulting in a more homogeneous and stable structure. Thus, one also minimizes the probability of deformation. The uniformity of the heat treatment can minimize non-uniform stresses in the material.
For example, I bought a heat lamp that gives off about, 50°C of constant heat. I place my small coasters under this heat lamp for about 4-5 hours. So it is like a small wellness treatment.
PLEASE make sure that the heat does not exceed 50°C! Also the nice oven in your kitchen is NOT suitable for tempering! Better still would be a small incubator, which you then use only for resin artworks ;)
So to protect resin creations 100% from bending, my very personal tip is to install additional stability. This would be, for example, a layer of JESIN on top (when casting in a silicone mold), or then underneath (in the finished demolded artwork). JESIN has a unique stability in relation to heat and protects the RESIN from bending! If u wanna know how I am pouring RESIN & JESIN un can find here an amazing tutorial blog post: RESIN & JESIN TIERED TRAY
So put on your coolest resin masks and let's conquer the world of epoxy - without melting shocks and with lots of creative magic! Your artwork will look so hot, even the sun will be envious.
Now that you know the secrets behind epoxy deformations in heat, you'll be ready to master your DIY creations without any heat hassles. Keep your artwork cool and your imagination hot - you're the real DIY heroes at the party of creativity!
Your MRS. COLORBERRY