Tung oil protects wood from moisture and gives it a nice natural look. But it does take a long time to dry, which puts people off. While there are no shortcuts, there are some simple tricks you can speed things up. Read on to learn more about tung oil drying times and how to speed them up.
How Long Does Tung Oil Take to Dry to Touch?
There is a difference between drying and curing tung oil. Curing time is the amount of time that the oil needs for the reaction to completely finish. The wood is not able to withstand regular use and it won’t be water resistant until the oil has fully cured. However, you don’t need to wait for it to cure between coats, you just need it to be touch dry.
The time that it takes for tung oil to be dry to the touch varies depending on the product you are using. Pure tung oil without any additives takes between 24 and 72 hours before it is dry and ready to recoat. However, a lot of modern tung oil finishes have drying agents mixed in to speed the process up. These can be touched dry in as little as 30 minutes. Just make sure to check the guidelines on the packaging before you get started.
How Long Does Tung Oil Take to Cure?
It’s important that you allow tung oil to fully cure before you use the item. If you don’t, you can damage the finish. Pure tung oil takes a very long time to cure. In some cases, you have to wait 30 to 45 days. However, polymerized tung oil dries much faster.
The curing process describes polymerization. When you apply the oil, lots of separate molecules join together to form chains (called polymers) as the oil dries. These chains are what forms the protective finish on the wood. Ordinarily, this process takes a long time, but you can buy polymerized tung oil. This oil has been treated before packaging so the polymerization process has already started and it cures much faster once you apply it. Polymerized tung oil should cure in around a week.
What Affects Tung Oil Dry Time?
Moisture needs to evaporate for finishes to dry on wood. In humid conditions, where there is a lot more moisture in the air, this process is much slower. Check humidity levels before you start your project to minimize drying times.
Cold temperatures slow down drying times too. When it is warm, moisture evaporates much faster and the polymerization reaction happens quicker. Ideally, you should keep a close eye on the weather and choose a period that is warm but not too humid.
Polymerization requires oxygen, so air circulation is crucial. If you apply the tung oil indoors and you don’t have good circulation, drying and curing times will be significantly longer.
Thickness of the Coat
Thick coats of tung oil take much longer to dry. There is often a difference between products and many contain thinning agents. If you are using one of these diluted products it will dry faster than pure tung oil.
How to Make Tung Oil Dry Faster?
1. Apply and Let Dry in Low Humidity
One of the easiest ways to make tung oil dry faster is to apply and let it dry in low humidity. Ideally, you should apply the oil when humidity is 50% or lower. Anything higher than that and drying times will be affected. You can find humidity readings on the weather forecast, which helps you pick a suitable time. If you are working indoors, you can use a dehumidifier to manage humidity levels.
2. Apply and Dry in Warmer Temperatures
Checking the temperature is crucial too. You don’t need to pick the hottest day of the year, but if you apply the oil during a hot spell, it will dry much quicker. The ideal temperature is between 60 and 80 degrees Fahrenheit. Again, check the weather forecast and find a period where the temperature is consistently high enough.
Learn if tung oil is flammable here.
3. Place Wood Project in a Well-Ventilated Area
When you leave the piece to dry, make sure that it is in a well-ventilated area. At the very least, open some windows and doors to improve air flow. You can also put in a room with a good ventilation system like the garage, and put fans in to run air over it. The more you can do to improve ventilation, the faster it will dry.
If you are desperate to improve drying time, you could use a hairdryer. This pushes a lot of air over the surface and increases the temperature at the same time. But you will still have to stand there for a long time while it dries.
4. Dilute Your Tung Oil and Apply Thin Coats
Some tung oil finishes are already diluted but if you are using pure oil, you can dilute it yourself. This helps it absorb into the wood better and dry faster. Usually, you use mineral spirits to thin the oil. The mineral spirits evaporate very quickly, leaving behind the oil to dry.
Thinning it is very simple. Take a plastic bucket and mix 2 parts tung oil to 1 part mineral spirits. Stir it around until it is fully combined and then apply it as you normally would. Do not dilute it any more than this. Sometimes, people thin the first coat to help it penetrate better and then use non-diluted oil for the rest of the coats. However, you can thin all of the coats if you like.
If you want to avoid using a strong solvent, you can also thin tung oil with citrus solvent using the same method.
5. Wipe Excess Tung Oil After 20/40 Minutes
Tung oil soaks into the wood and saturates it and then the excess seeps out and sits on the surface. This will eventually dry and the wood will be able to absorb more oil. However, you can speed things along if you remove the excess and let the oil in the wood dry before applying more. Once you have applied the oil, leave it for 20-40 minutes and then wipe the surface with a cloth.
6. Avoid Applying on Wet/Damp Wood
Applying oil to wet or damp wood is always a mistake. You’re just adding more moisture to the oil, so the drying time is extended. People often make this error when they clean the wood first and don’t give it long enough to dry before oiling. It’s important that you clean the surface thoroughly, but give it a few days to dry properly afterwards.
7. Only Apply a New Coat When Current Coat is Completely Dry
If you try to rush the job and apply a new coat before the current coat is dry, it will actually end up taking you longer. The new coat of oil adds more moisture and saturates the wood. The excess oil will leach out and sit on the surface, stopping it from drying quickly. Make sure that you let the current coat dry properly before starting another.
How Do You Know When Tung Oil is Dry?
The most obvious way to tell is to touch it. If it feels completely dry and it’s not sticky at all, you should be ready to recoat. Appearance is a good indicator too. If it looks wet and shiny, give it some more time. But when it is dry, it will have a glossy look.
If you are still unsure, you can try sanding it gently. Tung oil doesn’t require sanding between coats, but it shows you whether it’s dry or not. If it is still slightly wet, you won’t be able to sand it because the paper will get clogged with oil. But if it sands normally, it’s dry and ready to recoat.
Can You Get Away With One Coat of Tung Oil?
No, there is no point putting a single coat of tung oil on because it won’t protect the wood or give you the aesthetic you want. Normal tung oil needs at least 5 coats to give you adequate protection. You need to make sure that each coat is properly dry before moving on to the next one too. If you are looking for a quick job, tung oil is not the finish for you. But if you take the time to do it well, it looks great.
What To Do if Your Tung Oil is Sticky?
Tung oil should not feel sticky or tacky when it is dry. If it does, it may just need longer to fully dry and cure. However, tung oil sometimes remains sticky, even when it has dried properly. This happens when the temperature or humidity is not right or the oil is applied to wet or damp wood. Applying too much oil and failing to wipe off the excess can create a sticky finish too because a thick layer sits on the surface.
You can solve this problem by dissolving the excess on the surface and wiping it away. Use mineral spirits or turpentine to sprinkle over the sticky areas while also soaking a rag. Leave it for half an hour and then use the rag to wipe the surface. You can then reapply a very thin coat of tung oil and let it dry.
If this doesn’t solve the problem, you may need to remove all of the oil and start again. Use a solvent-based paint stripper or simply sand the wood back and start again.
Tung oil is a great natural finish for wood but it does require some patience. You can use the tips on this list to speed up drying times, but you still need at least 5 coats with plenty of time to dry between them. If you rush it, you’ll end up with a sticky finish that requires more work to fix. So, if you aren’t willing to be patient, tung oil isn’t the right choice.
Jamie is the founder of The Backyard Pros. When he was 15 years old he started working at a garden centre helping people buy plants, gardening products, and lawn care products. He has real estate experience and he is a home owner. Jamie loves backyard projects, refinishing furniture, and enjoys sharing his knowledge online.