Tung oil is a popular choice to waterproof wood with as it’s both an eco-friendly and waterproof oil finish.
One of the other reasons why tung oil is great is due to the fact that it protects woodwork from weather elements.
Is Tung Oil Waterproof?
In short, tung oil is not only waterproof, but it’s also extremely safe to apply on any surface regardless of what it’s made from.
The way tung oil works is that it absorbs around 12% of the atmospheric oxygen in order to form a waterproof layer on top of the applied surface.
As the tung oil is left to react with the oxygenated air, its components will continue to crosslink and polymerize, making a thin, water-resistant film.
In other words, by applying tung oil, you’re preventing moisture or water from seeping into your woodwork and susceptible surfaces.
How To Apply Tung Oil
Using tung oil is pretty simple and here’s a quick list of how you can do that easily:
- Prepare the surface for coating with oil by cleaning off any debris, dirt, or grease.
- Remember that you can’t apply tung oil on top of other oil layers. You should strip previous oil films and then sand the surface.
- Use a lint-free, clean rag to apply the tung oil.
- Start by adding only a few drops of tung oil.
- Make sure that you’re rubbing the rag along the grains of the surface.
- Avoid forming puddles of tung oil on the surface.
- Let the surface completely dry for at least 24 hours or more.
How Many Coats Of Tung Oil Are Necessary?
Generally speaking, you need to apply around four to seven coats of tung oil onto the desired surface. You should let the oil finish hardening for about two or three days at most.
With that said, how many coats of tung oil you’ll feel necessary will mainly depend on the kind of oil you’re using.
For instance, pure tung oil takes longer to dry off and needs constant reapplication as the years go by. As a rule of thumb, you should once a week every month or at least one time per month.
Additionally, don’t rush the process of applying pure tung oil, otherwise, you’ll cause the surface to wrinkle. In which case, you’ll need to sand it down.
Oil blends or varnishing wipes, on the other hand, are subtle and rich in resin. Using them is fairly easy because you just wipe the cloth across the surface.
This is a great choice because the oil will wipe off smoothly and won’t wrinkle too easily. Typically, it only takes several minutes for the oil to dry completely before you sand it.
How Long Does Tung Oil Take To Dry?
Tung oil is a natural drying oil. Pure tung oil takes at least three days to dry while oil wipes will only need 30 minutes to completely dry.
With that in mind, there are many determining factors that affect how long tung oil will take to dry atop a surface. For starters, low temperatures and high humidity make it harder for tung oil to fully dry, meaning, it’ll take longer than expected.
You should leave the wood to dry out in a region where the circulation is good. That way the oil has enough air to properly harden.
How Long Does Tung Oil Waterproofing Last?
Since pure tung oil is composed of only natural elements, both its shelflife and how long it lasts pose a challenge.
The minimum amount of time a tung oil’s waterproofing will remain is around six months. Simply put, you’ll need to reapply additional films of tung oil at least twice every year.
Make sure that you keep the coating as even as possible so that you don’t end up ruining the surface with multiple layers of glue.
It’s also as important to let the tung oil cure for around 30 to 45 days.