Before Tung oil can achieve the hard and moisture-resistant finish that it is known for, the wood oil has to dry. So how long does it take Tung oil to dry?
It takes a few days for Tung oil to dry. On average, Tung oil will dry enough for recoat 24 hours after the first coat was applied but it will take about 3 days for all the coats of the wood oil to dry.
Tung oil will take longer to cure as the wood oil cures based on oxidization and polymerization. The number of Tung oil coats, humidity, and ambient temperature all determine how long it will take for the Tung oil to dry.
But there is more to know about the dry time of Tung oil. For instance, how long should Tung oil dry between coats? Let’s find out.
How Long Should Tung Oil Dry Between Coats?
You should let Tung oil dry for at least 24 hours between coats. This is to allow enough time for the Tung oil coat to dry and harden before a recoat.
You should know that pure Tung oil takes longer to dry than refined or processed Tung oil. On average, pure Tung oil needs to dry for 48 hours or 2 days before a recoat. While refined Tung oil like the Miniwax Tung oil will dry enough for recoat in about 24 hours.
This is because Tung oil in its pure state is thick and without any solvent or additive. While processed Tung oil contains additives and solvents that make it dry faster.
If you recoat Tung oil too soon, the Tung oil finish will take several days to dry. Also, the wood oil will continue to smell due to the high moisture content in the wet Tung oil undercoat. Recoating Tung oil too soon will also make the finish streaky and sticky.
The biggest factor that determines how long Tung oil has to dry between coats is the ambient temperature. The ideal temperature for Tung oil to dry is between 60- and 80-degrees Fahrenheit. But the temperature isn’t the only factor that determines Tung oil’s dry time. Let’s check out other factors below.
Factors That Influence Tung Oil Drying Time:
The following factors determine the dry time of Tung oil:
This refers to the moisture content in the atmosphere. Tung oil should be applied when the humidity is lower than 50%. If there is high moisture content in the atmosphere, the room will feel moist and wet and this will affect the drying time of the Tung oil. If the humidity is higher than 70%, the dry time of the Tung oil can be doubled.
You should know that room humidity tends to be higher during the cold winter months so it wouldn’t be a good idea to apply Tung oil during these months. You can reduce room humidity by using a dehumidifier.
2. Room Temperature
The room or ambient temperature influences the dry time of the Tung oil. Tung oil should be applied when the room temperature is at or above 60-degrees Fahrenheit.
At this temperature, the Tung oil will dry properly. If the temperature drops below 40 degrees Fahrenheit, you shouldn’t apply Tung oil because the Tung oil will turn sticky.
3. Paint Flow
This refers to how thick or thin the paint is. If the Tung oil is thick, it will take longer to dry because there will be more oils in each coat.
If the Tung oil is thin, then the Tung oil will dry and even cure quicker. Painters generally advise thinning Tung oil before applying it so the wood oil can dry faster. You can thin Tung oil with mineral spirits.
4. The Number of Coats
Ordinarily, you need 4-5 coats of Tung oil for proper coverage. The more coats you add, the longer it will take for the Tung oil to dry.
5. Air Circulation
The airflow around the Tung oil coating also influences the dry time of the wood oil. However, you should know that this influences the cure time of the Tung oil more than the dry time. Speaking of the cure time of Tung oil, let’s find out how long it takes for Tung oil to cure.
How Long Does It Take Tung Oil To Cure?
It takes at least 3 days for Tung oil to cure. Tung oil cure time refers to how long it takes before the wood oil becomes fully hard and moisture-resistant. Unlike the dry time of the Tung oil that is influenced by temperature, the cure time is influenced by dry air. This is because Tung oil dries through oxidization and polymerization.
Oxidization is the process where dry air gets into the Tung oil. When the Tung oil is dry, this means that moisture in the wood oil has been fully evaporated. But this is where the curing process begins.
After the wood oil is dry, air (or oxygen) in the atmosphere gets into the wood oil. This process is called oxidization. The air that gets in the wood oil causes a reaction in the wood oil.
This reaction causes the oils and molecules in the Tung oil to combine. This process is known as polymerization. So the air causes the wood oil to bind until it is fully compact and hard. The compactness of the wood oil particles is what makes it very difficult for moisture to penetrate through the Tung oil. This is why Tung oil only becomes water-resistant after a few days when the wood oil has cured.
Technically, this means that the cure time of the Tung oil is a combination of the dry time and the oxidization time. This is why it takes longer for Tung oil to cure. You should also know that it can take pure Tung oil a few weeks to fully cure.
Now, let’s check out how to speed up Tung oil dry time.
How To Speed Up Tung Oil Dry Time? (Made Easy)
Bad news – There is no specific way to speed up Tung oil dry time but there are a few secret methods that work and this guide will reveal them all. The first on the list is to:
Method #1: Thin The Tung Oil Before Applying It
You can make Tung oil dry faster if you thin the Tung oil before applying it. One major reason Tung oil takes days to dry is that the paint is thick and you need at least 4 coats of it on wood. That’s a lot of oils on the wood surface and painting 101 teaches that the thicker the coat, the longer its dry time.
So to speed up the dry time, you can make the Tung oil lighter by thinning it with mineral spirits. Ensure to measure the right amount of mineral spirits depending on the quantity of the Tung oil. A good rule of thumb is 2:1 (Tung oil to mineral spirits). Here is how to do thin Tung oil:
- Get a clean plastic bucket
- Pour the required amount of Tung oil into the bucket
- Measure the mineral spirit
- Add the mineral spirit to the Tung oil
- Stir the mixture using a paint mixer for a few minutes
- Apply the thinned Tung oil
Method #2: Improve Air Circulation
This is more of a tip than a method and it has more effect on the cure time than the dry time since Tung oil cures based on oxidization. Improving air circulation helps the Tung oil to harden quicker. You can improve air circulation by:
- Opening all windows and doors
- Open the air vents
- Turning on the fans
- Applying the Tung oil outside
- Setting the air conditioner on ‘blow’ or ‘fan’ mode.
Method #3: Use A Hairdryer
This method is known to increase the dry time of Tung oil by at least 50%. Hairdryers can generate heat over 100 degrees Fahrenheit. At this temperature, the moisture in the Tung oil will evaporate faster causing the Tung oil coating to dry in hours rather than days. Here is how to do this:
- Turn on the hairdryer
- Set to medium heat
- Move the hairdryer over the Tung oil coating for a few minutes
- Increase the heat of the hairdryer
- Move the hairdryer over the Tung oil for 60 seconds
- Turn off the hairdryer and let the Tung oil dry completely.
You should know that it’s not advised to dry the Tung oil completely with a hairdryer. While it’s tempting to do this, drying the Tung oil completely will cause the Tung oil to crack and peel off.
This is because the Tung oil would have dried too fast and oxidization did not occur. So the oil particles did not bond and with time, the wood oil will split and fall off.
Method #4: Use A Dehumidifier
This method works better when you apply Tung oil during the cold winter months. During winter or heavy rainfall, the room humidity is usually more than 50%.
If you apply Tung oil during this period, the oil will not dry but you can use a dehumidifier to reduce the moisture in the air so the Tung oil can dry properly. To do this, all you need to do is to turn on the dehumidifier.
Here are a few other tips to make Tung oil dry faster.
- Apply Tung oil early in the day to take advantage of sunlight
- Apply Tung oil outdoors where there is better airflow
- Apply light coats
Now, let’s figure out how to tell if Tung oil is dry enough.
How To Tell If Tung Oil Is Dry Enough?
The following signs will indicate when Tung oil is dry enough:
- When you can sand the Tung oil – If the Tung oil hasn’t dried, you wouldn’t be able to sand it. This is because the sandpaper will get clogged quickly with oils. But, when the Tung oil is dry enough, the sandpaper will move freely on the Tung oil without getting clogged.
- When the Tung oil stops smelling – When Tung oil is wet, it will smell because the oils have not been evaporated but when the wood oil is dry, it won’t smell as much.
- When the Tung oil is moisture-resistant- When the Tung oil has fully dried, it will become water-resistant and moisture will not get into the oil.
- When Tung oil gets glossy – When Tung oil is not dry, it will appear wet but when the oil is dry, it will be glossy.
Overall, Tung oil takes a few days to dry and this is because the wood oil is thick and as such, it takes several hours for the oils to become dry.
The cure time however has to do with oxidization and only when the Tung oil cures it becomes water-resistant. This also takes a few days but you can speed up the dry time of the Tung oil by using any of the methods discussed above.