Why Is My Epoxy Resin Still Sticky?

January 5, 2017

You’ve heard us say how easy it is to use ArtResin epoxy resin.
And it IS easy … but it’s not foolproof :)

Every now and again, you might find soft, sticky areas in your resin application that don’t seem to be curing properly, or the entire thing still feels "tacky" after a few days .....

Why is my epoxy resin still sticky? And what can I do about it?

Well, the first thing to know is that epoxy resin comes in 2 parts:
a resin and a hardener.
When these two parts are mixed according to directions, a chemical reaction occurs which causes the liquid mixture to catalyze.
If this chemical reaction is somehow prevented or disrupted, a perfect cure is no longer possible, and the result is a sticky mess!

Read how to measure & mix epoxy resin!

The following are some of the common reasons epoxy resin might not cure properly:

1. Not Measuring Accurately

Some people think that adding more hardener will make the cure harder, or cause it to cure faster. Unfortunately, deviating from the 1:1 mixing ratio does the exact opposite!
ArtResin is a 1:1 mixing ratio and ensuring this delicate balance is imperative. If the parts are not equal, the resin will not catalyze properly and will remain uncured and sticky.

2. Under Mixing

Once you've ensured your mixing ratio is accurate and equal, it's important to mix
both parts together thoroughly. Again, if any material cannot catalyze properly by
any means, including not being blended well enough, it will not be able to cure
fully. Mixing vigorously for three to four solid minutes, scraping the sides and
bottom of the container, should ensure everything can thoroughly catalyze.

3. Dirty or Wet Utensils

Water and Resin are not friends :(
Even the tiniest drop of water or other contaminant can cause a host of problems, including cloudiness, bubbles and an improper cure. Ensure your measuring cups, mixing cups, stirring spatulas and spreaders are all completely clean and dry for best results!

Read how to clean resin tools & accessories!

4. Temperature & Cure Time Of Resin

Cure time is affected by temperature.
Warmer temps accelerate cure time and colder temperatures slow down cure time.
The ideal room temperature for mixing ArtResin epoxy resin is between 75 and 85 degrees F or 24 - 30 degrees C.
If it’s colder than that, the resin will be thicker and harder to mix, will have more bubbles and will take longer to cure until it’s dry to the touch.
We have a couple of space heaters at ArtResin HQ and we turn them
them on the day before we plan on resining to ensure the room, and the resin, is warm enough.

Read more details about the perfect temperature to cure resin.

5. Mixing Resin Brands

Don't replace the ArtResin resin or hardener with another brand of resin or hardener
thinking it will be the same. Every paired resin and hardener within a brand's kit
work together as a system and cannot be reliably interchanged.

Don’t learn the hard way :)
Follow our simple how-to instructions, measure and mix properly, and you’ll have no difficulty using and applying ArtResin to your project!

Okay, great.

But I already have soft, sticky areas that didn't cure properly. What should I do now?

Don't worry - all is not lost!

Resin that remains sticky days after being poured will stay sticky indefinitely unless the following measures are taken to fix the situation.

1. Scrape

You’ll have to scrape off the wet material as best you can and discard.
( Don’t worry - your artwork underneath will not be disturbed. )
Be sure all the liquidy resin is removed ( tacky is ok ) because if you pour fresh resin on top, the liquid could eventually leak out from under the new resin coat.

2. Fill

If after scraping, you're left with a deep divot or crater, patch in some new thoroughly mixed resin just in that spot.

3. Sand

Next, lightly sand the entire piece (including the cured patch, if you needed a patch)
Be sure to wipe the entire surface to remove any dust from sanding. The sanding provides some tooth to the first coat so the second layer will adhere properly.
Don’t be scared if it looks like a mess at this point - when you pour the second layer, it will look great!

Read how to sand between coats.

4. Pour A Second Coat of Epoxy Resin

Obviously you need to wait until the first layer and patch are 100% cured before adding more resin on top.

Read how to pour a second coat of epoxy resin.

Do you have any other tips on how to avoid improperly cured resin spots?

Comment below - we'd love to hear from you!

Watch Dave's video on applying a second coat of ArtResin!

Do you want to learn more about troubleshooting epoxy resin? Read our guides below:

About the author: Joanne Wright

I'm Joanne, the Marketing Content Writer at ArtResin. Originally from Canada, my home is now Indianapolis, Indiana. My love of all things creative and my entrepreneurial heart means I’ve worn many hats over the years including fashion producer & stylist, retail store owner, t-shirt designer, and even vegan baker! I...

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