Knowing how long it takes for two part epoxy to dry is a question that many folks have. It’s a super important question, for if you don’t know how long the epoxy will take to cure, you won’t know when you can use the surface of whatever it is that you are gluing or coating.
Are you applying it to a floor? A countertop? Furniture? The answers will be different in each case. We’re here to help with this guide on all things related to epoxy and its curing time.
First, let’s just quickly talk about the difference between one part and two part epoxies. Two part epoxies have an activator or hardener that must be mixed with resin before use (certainly not after!). The mixing ratio is usually 1:1 by volume or 2:1 by weight.
One part epoxies do not need any activator or hardener added before they are used because they already have them mixed in! This makes one part variety pretty easy and convenient to use, but there are tradeoffs too – one being longer drying times than 2 parts varieties (more on this later).
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How long does 2 part resin take to harden?
You’ve been asking yourself this question for a while now—and you’re not alone. Many people who are new to the resin game have this same question. So, how long does it actually take?
Resin takes between 12-24 hours to harden, depending on how much was used and the conditions under which it was applied. The larger the puddle of resin, the longer it will take to dry.
If you want to save time and speed up your hardening process, using a heat source is a great option but be careful with this method as too much heat can cause your resin to bubble.
How do you know when epoxy is fully cured?
- You can scratch the surface of the cured epoxy, but if you do so, what’s underneath is still sticky.
- When you press on the epoxy, your finger leaves a dent in it.
- The epoxy has a cloudy or hazy appearance.
How do you speed up 2 part epoxy?
If you want to speed up the curing process, there are a few things you can do.
- Increase the temperature. This is one of the easiest ways to speed up 2 part epoxy drying time. Turn up your house’s heat, place the piece on top of a cold cup of coffee, or leave it outside in the sun. If you have a workshop and an electric heater, this could be your best bet—as long as it’s not close enough to melt or damage your project.
- Blow on it while fanning it with a small fan like this one. The blowing will help warm it and evaporate some of the moisture, while the fanning should reduce humidity around it and help separate particles that might otherwise stick together as they cure.
- Use UV light (if applicable). Some special formulas harden when exposed to ultraviolet rays so you can use a UV lamp like this one to speed up curing times (check if your formula is compatible before using).
How long does the second coat of epoxy take to dry?
The time it will take for the second coat to dry depends on the thickness of the first layer and whether you’re using epoxy resin or coating.
Here are some guidelines for each product:
- Epoxy resin: If possible, wait at least 24 hours before applying a new layer of resin to ensure that it’s completely cured. Applying another coat in less than 24 hours could cause bubbles, bubbles, or cracks to form. However, if your project must be completed quickly due to an upcoming event, you can apply a second layer of epoxy after 8-10 hours by using a heat gun or hair dryer on low until the surface is tacky. Just make sure not to overheat because this will cause yellowing as well as create more bubbles than normal.
- Epoxy coating: It’s best not to apply another coat until 72 hours have passed from when you originally applied your first one because this is when most coatings reach their final cure point (meaning all solvents have evaporated out).
Does epoxy take 30 days to cure?
Ten minutes is a very short time for epoxy to set, but it’s still possible for curing to happen that quickly. The curing process of epoxy can take anywhere from 10 minutes to 30 days. It depends on the pressure and temperature conditions you apply during the process.
Most types of epoxy take between 24 hours and 7 days to fully cure, but there are some factors that can affect this time frame:
- At a normal temperature, most types of epoxy will set in 2-6 hours, while they attain full strength within 24 hours. However, when the temperature is low (but above freezing), curing may take substantially longer than one day.
- Increasing pressure during the cure cycle will reduce its duration — it might only take an hour or two at room temperature under high pressure.
- Increasing heat during the cure cycle will also reduce its duration — again, it might only take an hour or two at room temperature with heat applied to both sides of the joint.
Can you dry epoxy with a hair dryer?
If you’ve ever wondered how long epoxy takes to dry, or if it’s possible to dry it with a hair dryer, you’re not alone. The short answer is this: the drying time for epoxy resin depends on how much and what kind of epoxy you’re using.
Many people have tried putting their hair driers on high heat and blasting their freshly applied epoxy resin in an attempt to get it to dry faster, but this doesn’t work as well as they’d hoped. Instead of speeding up the process, a hair dryer often causes ripples and wrinkles on the surface of the epoxy.
If you absolutely must try to speed up your drying process in this way, use a heat gun instead of a hair dryer.
You can also apply multiple coats of epoxy to make sure that it dries thoroughly each time if you aren’t getting the results that you want from one coat at a time.
If you do decide to try using multiple layers or an external heat source like a heating gun or paint stripper, keep in mind that different types of resins will react differently under certain conditions.
It’s always important to read through the manufacturer’s directions before applying any type of coating.
Will epoxy set in cold weather?
Many people wonder if epoxy will cure in cold weather, and the answer is yes. When you’re using a two-part epoxy resin or a two-part casting resin, you want to make sure that both parts of the product completely mix together before applying it over the surface.
You can use a UV lamp on your part after mixing to help speed up the curing process, or you can use a heat lamp. If you happen to be above 65 degrees Fahrenheit then your part can set in the sunlight as well.
If you are working with colder temperatures, then it might be best to place your part under an infrared light bulb until it has fully cured.
It will take longer for your part to cure in colder temperatures because the lower temperature slows down chemical reactions inside of epoxies and casting resins that cure by exothermic reaction (heat producing).
Instead of hoping for warm weather all of sudden, why not try changing over to an epoxy system that cures more quickly and at lower temperatures? For example, many slow curing epoxy options have been formulated specifically for cold conditions. In fact, some products can even cure at frigid -20 degrees F!
This ultra low viscosity system offers outstanding physical properties with good elongation and peel strength while being totally waterproof and extremely resistant to chemicals like gasoline and oil solvents
How long should epoxy dry before sanding?
Epoxies can vary greatly in their set times. Most epoxies have a short pot life of somewhere between 20 to 60 minutes, but they often take around 24 hours to fully cure.
Full cure is determined by having a tack-free surface and reaching 90% of the final hardness of the formulation. In most cases, this is not a problem for us because we usually allow it to sit for at least eight hours before even thinking about sanding it down.
If you need your epoxy to be very hard in order to sand it down quickly, consider using an epoxy that has a higher final hardness or uses aggregate in its formulation (such as countertop epoxy).
These two types of systems will typically dry harder and faster than standard casting resins and will also dry more uniformly than casting resins that use fillers or pigments.
To recap the important points:
- Make sure you have the right amount of epoxy and hardener. You should use equal amounts of each component or measure out precise ratios (as required by your manufacturer’s instructions).
- Use glue sticks to apply the epoxy to surfaces that need bonding. This will help you keep track of how much is left in your mixing cup, while also preventing waste.
- Ensure that both components are stirred thoroughly before applying them to surfaces for bonding. Carefully read through any instructions included with your epoxy kit before getting started!
- Wait until it has fully cured before doing anything else with your project. Epoxies can take anywhere from a few hours to several days depending on their formulation and application conditions. It’s best to leave it alone for at least 24 hours just in case.