Why is my resin cracking?

If you are new to working with epoxy, it is no surprise that you could be confused about the whole process. One of the most confusing things for many people is resin cracking.

This article will explain what causes cracks in epoxy and how you can prevent them from happening.

How do you keep epoxy from cracking?

You can keep epoxy from cracking by using a release agent and the right hardener. Here are some options:

  • Use a fast hardener and slow resin. This will give you a quick cure time and little chance of delamination.
  • Use a fast hardener with medium resin, or use medium resin with a slow hardener. This increases the bond strength by allowing the two components to form at different rates within the same pot life period, resulting in a strong bond that is less prone to cracking when cured under pressure or stress.

What causes cracks in epoxy?

Cracks in resin can be caused by a number of things. The most common cause is improper mixing of resin and hardeners.

Make sure you follow the instructions on the package exactly and make sure that you are using the correct amount of hardener for your project.

If you don’t use enough hardener, it may not cure properly, allowing moisture to get into your finished piece (and thereby causing cracking).

If you’ve gotten as far as applying your epoxy but haven’t cured it yet, then another possibility could be that there is too much temperature fluctuation happening inside the curing area which causes some parts of your piece to cure faster than others—and this uneven curing will cause cracks like these ones here in this photo from our gallery!

It’s also possible that there was an error during application itself: maybe some dust or dirt got into the mix before dropping onto surface? Maybe some water droplets fell during application process? Maybe something else happened during application process?

Does resin crack easily?

Resin can be a difficult material to work with, but it’s not impossible. If you’re new to working with resin and you want to start small, try making contact lenses or pendants.

If you want to make something big like jewelry, consider using castable wax such as Fimo Soft (which is not hard enough for crystals).

When starting out with Fimo Soft, keep your projects small until you get a hang of working with this material. No matter how careful we are when making our pieces, sometimes defects happen because of time constraints or lack of experience.

This is why many artists prefer crafting their creations from scratch instead of using pre-made kits like Fimo Fun Factory by Premo!

Does resin crack over time?

  • Resin will crack over time if it is exposed to the elements. Rain, snow, and ice can all cause resin to crack.
  • Resin will crack if it is exposed to UV rays. Sunlight will cause your resin pieces to break down and then turn into dust.
  • Resin will crack if it is exposed to heat around the 80°F mark (25°C). The higher the temperature, the faster that this happens! This goes for direct sun exposure as well as indirect heating sources such as radiators or ovens with pilot lights on them that are close enough together so they radiate heat from their glass tops onto each other which then bounces back onto whatever’s sitting on top of them–ahem…this includes chairs…and tables…and stools…etc etc etc 🙂 Do you get where I’m going with this?

How do you fix broken resin?

You can fix broken resin using a few different methods. The easiest way is to use a putty knife or wire brush to scrape off the excess resin.

If you’ve got a lot of cracks and they’re deep, this may not be enough—you’ll need to heat the area with heat guns, heat lamps, or even blow dryers so that it’s pliable again.

How do you fix resin mistakes?

So you’ve made a resin mistake. Don’t worry, it happens to the best of us! Here’s what you need to do:

  • Remove the top layer of resin from your project using an X-Acto or razor blade. Be careful not to damage the wood underneath as you remove excess resin.
  • Clean off any residue with water and let dry completely before applying another coat of resin. It’s important that there be zero dust or dirt particles on your surface before applying more resin—this will help prevent cracking later on in the process. If there are any traces left behind after cleaning, wipe them away with rubbing alcohol before continuing onto step #4 below (see Image 1).

Does epoxy crack in the cold?

Epoxy resin is a thermosetting plastic, which means that it cures at room temperature instead of needing to be heated.

How hot does epoxy resin get when curing?

So, what is the temperature of epoxy resin when curing? The answer depends on a few things, including the type of resin you’re using and how many catalysts were added.

Epoxy resins typically cure in a temperature range between 150°F to 200°F. Some brands can reach 250°F or higher depending on how many catalysts were added during the mixing process.

The length of time it takes for epoxy resin to fully cure also varies depending on the particular brand being used. In general, however, one coat will take 24 hours while two coats may take 48 hours or more.

If you don’t allow your epoxy to fully cure before applying additional coats then there’s a chance that these additional layers won’t bond properly with previous ones—causing cracking later down line (as well as making your project look less than perfect).

On top of that most products are designed to be mixed at room temperature so if they’re mixed outside this range then they typically won’t harden correctly either; ultimately leading back again into no bonding issues during future stages like sanding etcetera.”


Don’t let this discourage you from resin work! I think it’s a great material and it can be used for a variety of applications.

Just be sure not to overdo it when using epoxy resin, and remember that the best way to prevent cracking is to use less material than necessary on your project.

Photo of author

Martin Flood

Martin Flood has been working in the construction industry for over 20 years as a general contractor with expertise in remodeling projects that are large or small. He has furthered his career by specializing in epoxy resin flooring, providing excellent service to both commercial and residential clients. Martin’s experience enables him to offer professional advice on how to choose the right type of project based on your needs and budget.

Leave a Comment