When we talk about different types of wood finish, two types get mentioned regularly, and they are Danish oil and polyurethane varnish. The first one is a natural extract mixed with some additives, both natural and artificial. Polyurethane varnish is a synthetic product but may contain some natural additives as well. Today, both these finishes play a significant role in the field of woodworking.
You will find that each one has its pros and cons. In this post, we go into each type’s details and how we can get the best out of them. Once you have read this post, you should be able to decide when and where to use each one.
Danish Oil vs. Polyurethane
What Is Danish Oil?
Oil finishes enjoy wide popularity because of the way they penetrate deep into the wood. The result is that they not only enhance the looks of the wood but provide protection as well. If you use a film finish like lacquer, polyurethane or varnish, you get excellent protection, but they don’t do much to enhance the surface of the wood looks. With Danish oil, you get both protection and good looks. Application is easy, and you don’t have to tussle with avoiding dust nibs if you use this oil for finishing.
Danish oil contains oil with some varnish, and thinner added. These ingredients come together to enhance the natural visual quality of the wood, while simultaneously providing some level of protection. The main elements of Danish oil are usually boiled linseed oil and Tung oil. These oils are drying oils, which darken and enrich the wood with a natural look as they dry.
The varnish component may be varnish or polyurethane (which is also a type of varnish). Then, we add thinner to make the liquid spread more efficiently and penetrate deeper into the wood. The thinner we add usually comes as either turpentine or mineral spirits (paint thinner).
Getting The Best From Danish Oil
Here are a few tips on how to use Danish oil in the best way possible:
Ensure that the wood that you apply Danish oil to is not sealed, or the oil will not be able to soak into the wood. Thus, avoid using Danish oil on surfaces that have been painted or have a polyurethane film, lacquer, or varnish.
For making your own Danish oil, you should ensure that it contains ingredients with drying agents such as Tung oil and boiled linseed oil. Avoid adding oils that do not dry, for example, mineral oil. If you are going to add turpentine, using the type that comes from pine trees will give off a better smell.
While mixing Danish oil, so in a glass jar with a metallic lid. Plastic can react with the oil and may up ruining your finish. If you use a glass jar with a tightly-fitting lid, you can store your Danish oil for a considerable time.
Advantages Of Danish Oil
- The finish penetrates the wood
- It is simple to apply and reapply
- Wood can become even hot-water resistant with an application of Danish oil
- It serves as a sealant or primer
- You can add pigments to create different colored tints
- Addition of other oils can give the surface of the wood a glossy appearance
- After drying, the surface will not be sticky
- Waxing a surface finished in Danish oil can impart high polish
- Danish oil doesn’t take much time to cure
- You can get clear matte and satin finishes
- The resulting finish is light
- No yellowing with age
Disadvantages Of Danish Oil
- Less durable wood finish
- Cannot use it on wooden cutting boards
- It does nothing to make the wood grain smooth
- To be applied only to bare wood
- Maintenance and re-application is needed
What Is Polyurethane Varnish?
Polyurethane varnish is a product of the modern age. When you need to maintain woodwork and need a quick and easy solution for touching up your work, polyurethane varnish comes to the rescue. Let’s try to understand when and how to use this versatile wood finishing option.
Polyurethane is a synthetic resin, and we use this varnish to finish all types of wooden and non-wooden surfaces. It is a transparent film, resistant to water, mildew, and fungus. On drying, the polyurethane varnish forms a tough coating that is resistant to abrasions. An added advantage of this varnish is that it dries much faster than other varnishes. You can get polyurethane varnish in flat or glossy sheens.
You get three types of polyurethane varnish, water-based, solvent-based, and oil-based. The water-based variety is the most environmentally-friendly and safe one to use as compared to the solvent-based varnish. But the water-based ones are less durable and not so resistant wear and tear. You can get polyurethane varnishes specifically meant for use on particular surfaces like decks, cabinets, tables, and chairs.
Getting The Best From Polyurethane Varnish
The method of applying polyurethane varnish is by foam or brush. After applying a thin coat, you have to let it dry overnight. You need to sand the varnished surface lightly and wipe with a dry cloth before applying the next layer. It usually takes up to three or four coats for a satisfactory finish.
A word of caution about using oil-based polyurethane varnish is that it is highly flammable, so handle with care. Also, keep yourself protected from the volatile liquid and fumes by wearing protective gear like a respirator mask and gloves.
The drying time of solvent-based polyurethane varnishes may increase in cold or humid conditions. You need to ensure that the previous coat is completely dry before you apply the next one. Be careful about dust as polyurethane has an affinity to dust. Make sure that you work in a relatively dust-free area. If you are conscious of the environment, then using water-based varnish is a more environmental-friendly option.
Advantages Of Polyurethane Varnish
- Polyurethane varnish is highly durable
- Easy to apply
- Resistant to heat and chemicals
- Withstands wear and tear such as scratches
- Lustrous finish that deepens the color of the wood
- Disadvantages Of Polyurethane Varnish (H3)
- Water-based polyurethane lacks penetration power and will not change the color of the wood
- Can impart a “plastic-like” look to wood surfaces
- Many types are not UV resistant
- May become yellow over time.
- Can be difficult for other types of finishes to adhere to polyurethane surfaces
- Preferably you should not spray it but apply it with a brush
- Relatively more expensive than Danish oil
Now that you are familiar with both these types of wood finishes, you will be able to use them efficiently. As you may have observed, both Danish oil and polyurethane have their advantages and disadvantages. The trick is knowing when to use each one. We hope that you have been able to understand these two types of wood finish better and that you will be able to use them effectively in your future woodworking projects.