Knowing how long to wait before your epoxy resin has sufficiently dried—also known as the curing process—is essential to ensuring that your project doesn’t end up with sudden blemishes or other types of damage. Until resin has fully “dried” or cured, you’ll need to be wary when interacting with it.
Let’s go over the details on epoxy resin drying times, then at the bottom we’ll place a handy chart.
How long does it take for epoxy resin to dry?
Most people who ask this question are wondering about the curing time of otherwise finished epoxy. This means that they’ve applied every coat they need, cleared away any air bubbles, and are simply waiting to make use of their resin project. So we’ll start with that.
For large projects, such as an epoxy resin table top or bar top, the drying time for the final flood coat of epoxy is 72 hours, presuming you’ve maintained the recommended temperature range of 75°F to 80°F. This is the minimal amount of time suggested before interacting with your epoxy resin finish, as by then it will have cured 99% and be hard enough to withstand typical use without any issues.
However, epoxy resin has a unique trait. While 72 hours (i.e., 3 days) is the minimum time, epoxy will continue to dry/cure for a full two weeks.
This means that after about two weeks in an adequate temperature range, the epoxy will reach its full strength and durability.
There’s no need to wait the full two weeks for this to happen, though. Ordinary usage shouldn’t cause damage to the resin at this point, making this more of a technical note.
Are drying times different for each type of epoxy resin?
Some are, but not dramatically so.
The most common type of epoxy is table top epoxy. For this, the final dry/cure time in ideal conditions is 72 hours, as noted earlier.
There’s also deep pour epoxy, otherwise known as casting resin, which also takes about 72 hours to adequately dry/cure.
A third, less well known type of epoxy resin is marine epoxy. This type of resin tends to vary in its suggested drying time, due to the irregular climates it’s applied in. In ideal temperature settings, it can be as quick as 24 hours. In less than ideal settings, e.g., slightly colder, more humid locales, it can take as long as 4 days, provided some effort is made to maintain a reasonable temperature.
Marine epoxy resin’s drying times are determined by the type of hardener used as well. We’ll explain that next.
Marine epoxy dries/cures differently from other resins.
Unlike table top epoxy resin or deep pour epoxy, the marine epoxy has several types of hardener to choose from. Hardener is the component you mix with the pure resin to get two-part resins to harden and cure. For marine epoxy, each hardener is designed for specific situations.
A fast hardener will make the resin cure more quickly at a slightly lower temperature of 70°F. This is good for people who live in cooler areas and would have trouble getting resin to dry in a reasonable time due to temperature shifts. Fast hardener has a drying/cure time of 1-4 days at temperatures near 70°F.
A slow hardener will make the resin cure more slowly at higher temperatures of about 80°F. This is designed for people who live in hotter regions and need more time to actually apply the epoxy to their surfaces before it begins hardening too much. With slow hardener the drying time is still 1-4 days, but the maximum suggested temperature is much higher than fast hardener.
There’s also a form of marine epoxy resin that acts as a clear coat. This resin is typically added after using one of the other marine resins and letting them dry. Clear coat marine resin has the same average drying times of 1-4 days as fast and slow marine resin, but cures best at 75°F.
Drying times are also determined by the type of coat.
So far, we’ve explained the drying times of epoxy resin after you’ve applied the final coating needed for your project. However, drying times are relevant at other points in most epoxy projects, so now we’ll dig into the finer details.
What are the types of coatings and their drying/curing times?
There are generally three types of resin coatings:
- Seal coats
- Flood coats
- Deep pour coats (deep casting coats)
You can learn more about each individual coat type here.
What is the drying time of an epoxy resin seal coat?
For a seal coat, you’ll almost always be applying more resin later. You’ll neither want nor need it to fully dry.
Typically, the recommended drying time for a seal coat is 4 hours. Wait this long after applying your seal coat, then you can apply another coat of any type, e.g., a flood coat or deep pour coat.
For seal coat applications, we recommend using our UltraClear Table Top Epoxy. It has a higher viscosity than deep pour epoxy—ideal for manual applications using a paintbrush.
What is the drying time of an epoxy resin flood coat?
As explained earlier, if the flood coat of resin is your final coat, the drying time is about 72 hours.
However, sometimes a flood coat is not your final coat. This happens when you need multiple flood coats for your project.
When applying a flood coat that isn’t your final coat, the minimal drying time is 4 to 10 hours. In this range of time, you can safely apply an additional flood coat.
If more than 10 hours have passed, but you still need to add another coat, you’ll want to sand the epoxy very lightly with 220 to 320 grit sandpaper (any in this range will do). This will prepare the partially hardened surface for an additional coat.
What is the drying time of an epoxy resin deep pour coat?
If the deep pour coat is your final coat, the drying time is about 72 hours within a temperature range of 60°F to 85°F. The humidity should be at or below 60% during this time.
If your deep pour coat is not your final coat, and you intend to apply more resin on top of it, the recommended drying/curing time is 12 to 24 hours. In other words, you should apply your next coat after 12 hours have passed but before 24 hours have elapsed. Keep in mind that this assumes you’ve maintained the appropriate temperatures and kept the humidity at or below 60%.
For deep pour resin projects that will receive a lot of interaction, it’s common to apply a final flood coat of table top epoxy, which is the strongest available epoxy resin.
Our UltraClear Deep Pour Epoxy is excellent for traditional deep pour coatings as well as for use in molds, resin art, and resin jewelry projects as a casting resin.
Is there a handy chart for resin drying times?
Yes, there is! Take a look at the chart below for a list of resin drying/curing times for each epoxy type.
Have questions? Want advice? Contact us!
For any questions or concerns regarding epoxy resin drying times, as well as resin projects in general, you can always reach out to us at UltraClear Epoxy. Our epoxy experts are ready to assist you with your epoxy resin projects.
You can reach us via phone or email here, and you can also text chat online with an expert by clicking the help button at the bottom-right of your screen.