Tung oil and varnish both have unique advantages. Tung oil provides a natural finish that penetrates the wood, making it ideal for surfaces where breathability and easy maintenance are desired. Varnish, on the other hand, creates a thicker, more durable protective layer, better suited for high-traffic areas.
Tung oil is one of the most water resistant of cuing oils and has a centuries-long history of use as a final finish. Still, it's no match for modern varnish in terms of durability.
Generally oil is better . varnish only gives a surface protection and in most cases subject to uv deteriation . Oil if applied in several coats soaks into the wood and prevents the ingress of moisture and in certain timbers found naturally like cedar which lasts well open to the environment .
It really shines as a kitchen finish, as 8 coats of pure tung oil last at least 8 years with heavy use.
No additional sealer is needed as the tung oil naturally seals and offers waterproof protection.
Tung oil is often recommended as a sealing oil for furniture because it protects the wood from moisture and stains.
Oiling Out—Today's Preferred Method
The simple process of oiling out is often touted as a safe alternative to applying retouch varnish in areas of dried oil paint films that have sunken in. And the process is safe and straightforward.
Overall, varnish is an excellent choice for those who want to protect their wood surfaces and maintain a natural appearance. Polyurethane is an excellent way to protect your wood surfaces from water damage and wear and tear. It is also ideal for enhancing the natural appearance of wood, as it offers a warm, amber tone.
Most surfaces will require 2-3 applications; however, very porous, old, or dried up surface may require 6 or more coats. Pure Tung Oil should not be used over any existing stain or finish. Strip completely to bare wood and follow the 'NEW WOOD APPLICATION' procedures.
Wipe-on poly or spar varnish will work on top of tung oil. This should protect the top from water damage, but it will show wear, so you will need to reapply every year or so.
With enough coats to fill the pores and scratches left in the wood, liquid water doesn't get through. Tung does this so well it was used for centuries in China to waterproof the hulls of boats. Nowadays, you can still use tung oil on a boat, but it's particularly useful on woodenware and outdoor furniture too.
The MinWax product is a mixture of tung oil and varnish and will seal the wood. The whole idea of tung oil is that it penetrates the wood and the microscopic tubes and holes that contain air in dry wood but really soak up water.
Teak oil is generally considered the best oil to treat wooden garden furniture. It provides year-round weather protection whilst emphasising the wood's natural colour. It does this by replacing the natural oils that are lost through weathering, and preventing the wood from splitting and warping.
When the wood no longer absorbs the oil, use another clean, dry rag to wipe all the oil away. Wipe away any pooled oil that oozes out of the wood grain over the next few weeks. Wait at least a month before using the butcher block for heavy-duty tasks, as Pure Tung Oil typically takes about 30 days to properly cure.
Oils protect by permeating the wood deeply, while varnishes work by forming a layer on the wood. Oil can be ideal for wood that gets wet frequently. Products like Biofa Ireland's non-toxic Weather Protection Oil or oil-based Exterior Wood Glaze/Varnish prevent water ingress and keep the wood protected.
After oiling out, wait until the surface is thoroughly dry before varnishing, which usually takes several days to a week or more.
The shine obtained with a wood oil is much softer and more natural than that of a varnish, and the touch is silky and very pleasant. So the best way to polish unvarnished furniture is to use wood oil.
Unlike oil finishes, varnishes provide a protective film over the wood. This allows them to offer a very high level of protection and durability.
Minwax® Fast-Drying Polyurethane
It's one of the most durable coatings for wood protection against scratches, spills and more, and is a clear coat. It can be used on both finished and unfinished wood projects, and is available in a variety of sheens. The fast-drying formula allows for quick recoats in 3-4 hours.
Minwax Clear Interior Tung Oil (1-pint) 47500000 at Lowes.com.
So if you're looking for a wood oil with either a matt finish, or being 100% natural and environmentally friendly is key, then Tung Oil is the best bet. Otherwise, for most surfaces we would actually recommend Danish Oil as it dries quicker and provides a harder wearing finish to wood.
Google seems to indicate that pure tung oil, not polymerized, with no dryers added, will keep in sealed can for several years... Of course much of what is called "tung oil finish" has little or no true tung oil and plenty of other oils and varnishes and driers. So be sure of what you've got...