There are plenty of times when adding a protective layer to wood is a good move, and two wood finishes that provide such protection are lacquer and polyurethane.
But how are these finishes different, what are the pros and cons associated with using them, and which is better overall? To know which is superior in the contest of lacquer vs. polyurethane, read on!
In This Article:
Differences Between Lacquer vs Polyurethane
In terms of durability, both lacquer and polyurethane are durable finishes. The strongest lacquer finish is post-catalyzed lacquer, while the strongest polyurethane finish is oil-based polyurethane.
Both finishes are about equal in terms of durability, and the strongest finish after these is acrylic lacquer.
Lacquer dries a lot quicker than polyurethane, which means you don’t have to wait as long to apply additional coats. In some cases you can apply several coats in just a couple hours.
Even if you’re using water-based polyurethane, it’ll still take several hours to apply the coats necessary to form an effective barrier.
In terms of versatility, polyurethane is more versatile because it can be used on many more wood surfaces. Lacquer is mainly used on high-end furniture and wood surfaces that aren’t going to be put in harms way often.
Polyurethane, on the other hand, can be used on everything from hardwood flooring to kitchen cabinets.
Both polyurethane and lacquer are replete with toxic chemicals, which means you need to be wearing proper safety gear when applying either; you should also be doing this in a well-ventilated room.
Water-based lacquer and water-based polyurethane don’t have a ton of chemicals, but even these finishes include a number of hazardous components.
Generally speaking, lacquer is slightly more expensive than polyurethane, mainly because of its components. That said, you could find a high-quality oil-based polyurethane that’s more expensive than average and low-quality lacquer.
Ease of Use and Application
Applying polyurethane takes longer, but this is a simpler process, especially once you get the hang of things. Applying lacquer—whether you’re using a natural bristle brush or a spray can—is more challenging because you have to apply quickly.
Plus, you can apply polyurethane in a variety of ways, whereas lacquer requires long, uninterrupted strokes to ensure a uniform coat.
Lacquer Basics: What Is It?
Lacquer is the result of dissolving shellac in alcohol, though it can be made of synthetic substances as well. When lacquer dries, it forms a hard, protective coat that’s smooth, glossy, thin, water-resistant, easy to maintain, long-lasting, and heat resistant. And unlike other finishes, lacquer doesn’t yellow as time goes by.
When in liquid form, lacquer will penetrate the wood’s surface before being absorbed by the pores.
Because of the qualities listed above, and because it dries quickly, lacquer is applied to high-end wood furniture.
Types of Lacquer
There are five kinds of lacquer: water-based lacquer, acrylic lacquer, catalyzed lacquer, nitrocellulose lacquer, and urushiol lacquer.
In many ways these lacquers are similar, but they differ in terms of application, use, and benefits. In other words, some lacquers are best for certain projects while others are best for different projects.
Water-based lacquer is different from the other lacquers discussed below, mainly because of its composition and application. Unlike other lacquers, water-based lacquer isn’t loaded with hazardous chemicals, meaning it’s more eco-friendly and safer to apply. It also dries quickly and is odor-free.
However, water-based lacquer is not as strong as acrylic or catalyzed lacquer, so it’s not as long-lasting as these lacquers. But it tends to be longer-lasting than nitrocellulose lacquer.
In addition to these benefits, water-based lacquer is also the cheapest option, mainly because it’s made of inexpensive components.
Developed in the 1950s, acrylic lacquers are often used on light wood, including balsa, birch, cedar, ash, and maple.
The main reason why acrylic lacquer is used is because it doesn’t yellow over time like other lacquers do. Plus, it’s more durable than other lacquers.
There are many kinds of acrylic lacquer, and one of the most popular kinds is CAB-acrylic lacquer. This lacquer is made with cellulose, acetate, and butyrate (hence the acronym). In addition to being more flexible than traditional acrylic lacquers, CAB-acrylic lacquers are also more crack resistant.
Because of its components, strength, and ability to dry “water-white,” acrylic lacquer tends to be more expensive than the other lacquers discussed here.
To prevent curing, lacquers are made with solvents. These solvents evaporate over time, and as they do the lacquer dries.
Catalyzed lacquers are different, however, because they go beyond simple solvent evaporation to form durable coatings. Specifically, catalyzed lacquers utilize acids that ensure a harder coat.
Some lacquers are manufactured to be catalyzed, but you can catalyze a regular lacquer by adding the right acid (or catalyzing chemical) to it.
Catalyzed lacquers became popular in the latter part of the 20th century, and today they’re used mainly to ensure a more durable finish.
Before catalyzed lacquers ascended to a place of prominence, both nitrocellulose and acrylic lacquers were essential to woodworkers. But because they’re more durable than these older lacquers—while costing about the same—catalyzed lacquers have become the new go-to for woodworking veterans and amateurs alike.
Nitrocellulose lacquer has been around since the 1920s, and while it’s used to finish a variety of wooden surfaces, it’s often associated with musical instruments, including, guitars, violins, pianos, and other wooden string instruments.
Up until the mid-20th century, this kind of lacquer was also used across the automotive industry, specifically as a durable coating for metal.
Once dry, nitrocellulose lacquer is smooth and glossy, and it’s more malleable than traditional lacquer.
And because this lacquer tends to become reddish-amber as it ages, it accentuate some woods and makes others look bad. For example, you won’t find this kind of lacquer on light woods because the colors don’t blend well.
If you’re going to use this lacquer, keep in mind that it doesn’t resist chemicals or liquids as well as other lacquers. Also, this lacquer is more prone to cracking, especially after a few years have gone by.
You’ll find wax and lacquer trees throughout Eastern Asia, and the resin that’s exuded by these trees contains the chemical component urushiol. If you’ve ever had poison ivy or poison oak, you’ve encountered urushiol before, as this is the chemical that causes skin irritation.
Originating in China, urushiol-based lacquer is approximately 4,000 years old. This kind of lacquer is used on furniture, instruments, and coffins, and it’s rare to find products made in America that utilize this lacquer.
Unlike other lacquers—which cure via chemical solvent evaporation—urushiol cures through oxidation and polymerization.
How to Use Lacquer
When it comes to applying lacquer, I like to use a brushing lacquer, specifically this one by Deft. It dries evenly, it’s easy to apply, and I like the look and feel once it’s dry. Here’s how I apply it:
Step 1: Apply a Sealer Coat
I pour a cup of lacquer into an empty container and then I mix this with a cup of lacquer thinner. Once there’s good blend, I grab a thick, soft-bristle brush and apply this mixture (the sealer coat) to the wood surface.
This coat is applied to lock any raised wood fibers in place; this makes sanding and adding subsequent coats easier.
Step 2: Lightly Sand
After the sealer coat has had ample time to dry, I grab some 320-grit sandpaper and I lightly sand to remove the raised wood fibers. You don’t have to apply a lot of pressure when sanding to remove the fibers.
You can feel the raised wood fibers when you go over the surface with your hand, so you’ll know you’re done sanding when you can no longer feel any fibers.
Step 3: Remove Leftover Dust
After you’re done sanding, grab a tack cloth and use it to remove any dust from the surface. It’s best to avoid using a wet cloth at this point to remove leftover dust, as making the surface damp before lacquer is applied can lead to an unsatisfactory result.
Step 4: Apply the Lacquer Directly
Now it’s time to apply the lacquer directly to the wooden surface. You should get enough lacquer on your brush so you can brush in long, uninterrupted strokes.
Avoid brushing in a back-and-forth motion, as doing so can dry out the lacquer quickly, which will lead to cracking, flaking and an overall mess.
Note: If the surface looks blotchy after you apply the sealer coat, don’t fill in spots that look under-lacquered; just let the lacquer dry and apply the next coat. Eventually, after enough coats have been applied, a uniform barrier will form—the lacquer coats just need time to bond.
Usually it takes three to five coats to form an effective lacquer barrier. That said, how many coats are required largely depends on the kind of lacquer you’re using as well as the surface it’s being applied to.
For example, if you’re lacquering a dining room table, you’ll need more coats, as this piece of furniture requires a solid, long-lasting barrier, which is what’s created when you properly apply multiple coats of high-quality lacquer to a wooden surface.
Here are a few tips and tricks to applying lacquer!
Polyurethane Basics: What Is It?
Polyurethane is essentially liquefied plastic that hardens once it’s been applied to a surface. Like lacquer, this finish is also water- and chemical-resistant, along with being scratch- and dent-resistant. And after it’s had ample time to dry, it becomes smooth and glossy.
Types of Polyurethane
Whereas there are many different kinds of lacquer, there are only two kinds of polyurethane: water-based and oil-based polyurethane.
Water-based polyurethane is an odor-free, easy-to-apply liquid that, when dry, forms a durable, smooth, and translucent barrier around the surface it’s been applied to.
A single coat of water-based polyurethane isn’t as strong as a single coat of oil-based polyurethane. That said, if you put down enough coats of water-based polyurethane, they can collectively form a barrier that’s just as durable and long-lasting as one formed by a few coats of oil-based polyurethane.
And when compared to oil-based polyurethane, water-based polyurethane is the more eco-friendly option, as it doesn’t have as many volatile organic compounds (VOC).
Also, water-based polyurethane dries quicker than oil-based, which is in part why it’s more expensive (by $3 to $5).
Oil-based polyurethane is much thicker than water-based polyurethane, and as it dries it develops a yellowish tint.
It’s longer-lasting and more durable than water-based polyurethane, mainly because of its thickness—this is why it’s used on surfaces that are frequently subjected to heavy foot traffic, such as hardwood floors and stairs.
It contains 450 to 500 VOCs, and because it emits a strong odor you should only apply it in a well-ventilated area.
Often, you can get a smooth, durable barrier with just a couple coats.
As far as drying time is concerned, oil-based polyurethane takes multiple days to dry, whereas water-based polyurethane takes just a few hours.
How to Use It
The process one must follow to apply polyurethane is similar to that which is used to apply lacquer, though there are some key differences.
Step 1: Sand the Surface
Before adding a polyurethane coating, you need to sand the wood’s surface. You should use 320-grit sandpaper to do this.
Sanding will remove imperfections and make the surface more receptive to the polyurethane.
Don’t bear down too much when sanding, for if you do you’ll remove too much material from the surface.
Starting at the corners, sand in an up-down motion.
You’ll know sanding is having the desired effect when the surface starts to get hazy. It may take 10 to 15 minutes to sand; how long it takes largely depends on how rough the surface is.
After you’re done sanding, vacuum the surface to remove leftover dust.
Step 2: Clean the Surface
Now it’s time to clean the surface with mineral spirits. Refrain from using water, as this can prevent the polyurethane from adhering and drying properly.
Dab some mineral spirits on a clean rag, a paper towel, or a paint brush to apply it. Make sure there’s proper ventilation when you use mineral spirits, as the fumes could make you lightheaded.
Step 3: Apply the Polyurethane
Now it’s time to apply the polyurethane. You should be generous when applying either water- or oil-based polyurethane.
When applying, brush in long, uninterrupted strokes. Also brush with the grain, and pay attention to spots that may need more polyurethane, like knots and crevices. It may take awhile to fill these spots, but doing so is necessary.
Once the surface looks cloudy overall, stop applying polyurethane.
Step 4: Let the Polyurethane Dry Before Repeating the Steps Above
Give the polyurethane plenty of time to dry. Then, once the polyurethane is completely dry, repeat the steps above. Use this step-by-step process to apply each coat until you reach the desired number of coats.
Step 5: Clean Up
Cleaning up polyurethane isn’t always the easiest job on the planet. Depending on the type of polyurethane you use, there are different methods to clean it.
If you’re using an oil based poly, you’ll need mineral spirits. For water based poly – some warm water and dish soap should do the trick.
Here’s how to apply polyurethane!
Lacquer vs Polyurethane: Advantages and Disadvantages
Using lacquer as a finish has advantages and disadvantages, and the same can be said for polyurethane. Check out the pros and cons associated with each finish before you decide on which to use.
Lacquer Pros and Cons
Pro: Quick Application
Whether you’re brushing lacquer or using lacquer spray, applying this finish is much quicker than applying polyurethane. It may take you just a few hours to put down several thin coats of lacquer, whereas it could take several hours to multiple days to form an effective polyurethane barrier.
Pro: Thin Yet Effective
Unlike polyurethane, the barrier created by lacquer finish is hard to notice, largely because the lacquer is absorbed by the wood’s pores. But despite being thin, lacquer finish can still be durable and long-lasting, especially if it’s applied properly and maintained well.
Con: Hard to Apply
Applying lacquer finish is harder than applying polyurethane. This is mainly because you need a large area (if you’re using spray lacquer) as well as the right protective gear.
And if you’re applying lacquer with a brush or a foam roller, you need to apply in long, uninterrupted strokes to ensure the lacquer doesn’t dry too quickly.
Con: Hard to Remove Dents and Scratches
Lacquer finish may be strong, but it’s not impervious to dents and scratches. And either blemish can be hard to address. Polyurethane, on the other hand, is easy to touch up.
Polyurethane Pros and Cons
Polyurethane finish is especially durable, in large part because of the way it hardens. Plus, you can apply numerous coats to ensure a thick, tough barrier.
When compared to lacquer finish, polyurethane is longer-lasting, in large part because it only breaks down gradually over time. Plus, it’s more dent- and scratch-resistant, which means you won’t have to repair it often.
It can also withstand wide temperature fluctuations as well as sustained exposure to the elements.
Con: Application Takes Awhile
One unavoidable downside associated with using polyurethane finish is the long application time. In other words, it takes awhile to dry and cure.
Because it takes a long time for an effective barrier to form, there’s more risk of something going wrong that affects the curing process.
Con: More Noticeable
Since the polyurethane barrier is formed above the wood’s surface, it’s thicker and therefore more noticeable (despite being translucent). So if you don’t want a thick barrier, it’s best to opt for lacquer. However, this could also be considered an advantage because you might like the sheen a polyurethane coating can result in.
When Should You Use Polyurethane?
Polyurethane is good for wooden floors, tabletops, cabinets, banisters, and certain kinds of furniture. Polyurethane can also be used on boats, and it’s often used to accentuate wood sculptures. Basically, polyurethane can be applied to almost any kind of wood surface that needs additional protection.
When Should You Use Lacquer?
Lacquer is often used on high-end wood furniture as well as fine wooden instruments. Like polyurethane, it can be used on virtually any wood surface.
That said, because it’s not as durable as polyurethane, it’s not used on floors and other surfaces that are put in harms way often.
What are the disadvantages of using lacquer?
Despite being durable, lacquer isn’t impervious to dents and scratches. Also, whether you’re spraying lacquer or using a brush, it takes awhile to apply this finish.
How can you tell the difference between lacquer and polyurethane?
Polyurethane is thicker, shinier, and used on a wider variety of surfaces. On the other hand, if you’re looking at finished furniture, there’s a good chance you’re looking at lacquer.
Which dries harder: lacquer or polyurethane?
Catalyzed lacquer dries harder than even oil-based polyurethane.
Can I use lacquer instead of polyurethane?
In most instances, yes. However, there are instances when polyurethane is better than lacquer and vice versa.
Is lacquer shinier than polyurethane?
Some lacquers are shinier than water-based polyurethane, but oil-based polyurethane is the shiniest of all the finishes discussed in this article.
What does lacquer do to wood?
Lacquer makes wood shiny, smooth, stronger, and more visually appealing. It also makes wood more resistant to the corrosive properties of water, chemicals, etc.
Is lacquer oil-based?
Most lacquers are oil-based, but not all of them. Water-based lacquer is the exception.
Final Thoughts on Lacquer vs. Polyurethane
Both lacquer and polyurethane are great finishes that you can use on a variety of different projects.
If you need maximum protection, go with a polyurethane finish. It creates a more durable barrier that sits on top of the woods surface which is perfect for floors and other high impact areas.
If you’re looking for a more high end finish, lacquer could be a better option. Both are pretty easy to apply, but polyurethane is more forgiving.
Ultimately, it’s hard to go wrong with either choice.