In the woodworking world, there are various options you can choose from when it comes to wood finishing. The choice you make for your finish is important like other important things in your life. The finish you will use to make the wood will either make or break your project.
Among the various existing finishes in the market are lacquer and polyurethane which are famous and commonly used by so many people.
These two are popular because they are simple to apply and easy to clean as well. Most of the time, people confuse these two products given their close identities.
However, there is a significant difference between the two and this article is going to give detailed information on their differences and answer some of the frequently asked questions.
What is Lacquer?
Lacquer is the most recommended by woodworkers and this is because it is easy to apply and dries quickly. Moreover, this finish provides you with a glossy and smooth finish. The finish is also durable and resists damages because it goes beyond the wood surface.
When you want to apply this finish, you will require a well-ventilated room, high volume, and low pressure.
There are three different types of lacquer including acrylic, water-based, and nitrocellulose. Regardless of their slight differences, they all are durable and dry quickly.
What is Polyurethane?
Lacquer is thin and blends easily with other coats used earlier and therefore it is easy to repair.
Polyurethane is another popular finish that is common with people and when applied to the wood, it provides a thick and smooth finish. If chemically translated, this product is a plastic in the liquid form but when it dries, it blends to the wood well.
Unlike lacquer, this product is thick hence it is not easy to apply unless one uses a thinning agent combined with a spray. It comes in two types (water-based and oil-based) which are both durable.
Also, since this product is thick, it is rarely applied using a spray and most people use a brush. The brush that is ideal for this product is a natural bristle brush since it cannot leave behind brush marks.
Polyurethane does not also penetrate wood because it is thick. It only coats the surface of the wood and gives a glossy end look.
Differences Between Lacquer and Polyurethane
We are going to compare these two products using different characteristics including cost, application, permanence, dry time, and quality.
These two products come at different prices depending on their formula, the name of the brand, and the quality. This makes it difficult to discuss the cost of each product.
However, we will look into the application costs. Polyurethane has less application cost than lacquer. This is because, unlike lacquer, polyurethane is thick and therefore hard to apply especially when the person applying is doing it for the first time.
However, with the use of a brush, one can easily apply it. Also, because the product is thick, it only requires a few coats to achieve the desired coverage.
Lacquer is thin and gives outstanding results when it is applied with a sprayer. This means that you need to have a sprayer or make a purchase which will take a large amount of money.
Lacquer requires more coats than polyurethane to get the desired results and this means you will have to spend more on the product.
Lacquer is easy to apply compared to polyurethane for various reasons. First, lacquer has watery consistency which sometimes makes the process hard but it is easy to handle. All you need is a white spirit for a solvent to solve your problem.
Although polyurethane is a liquid, it is still plastic. It is usually thick and handling it is hard. However, most people prefer it because it uses few coats to produce the desired look.
Still, it is still hard to apply or get a flawless look. Also, since polyurethane uses a brush to apply, it might leave some marks on the surface, and therefore it is recommended to get a fine brush to get good results.
Lacquer makes use of a sprayer and applies evenly making it easier to apply compared to polyurethane.
The first thing to understand is that wood absorbs liquids and lacquer usually acts like water. When lacquer absorbs into the woods, it forms a strong bond with it so that it becomes hard to break.
Polyurethane, on the other hand, is a polymer and does not absorb into the wood but only forms a coat. This makes it prone to peeling and cracking when it is exposed to a lot of heat.
Nevertheless, if applied well and on woods that are not exposed to heat, it provides a durable and resilient end product compared to lacquer which is prone to peeling, discoloration and requires constant maintenance.
Polyurethane, as discussed above, comes in two variances and that is water-based and oil-based. The water-based type takes a short time to dry compared to oil-based polyurethane.
Generally, polyurethane takes longer to dry. Lacquer, on the other hand, dries fast and is recommended by most woodworkers.
It can take a maximum of ten minutes to dry while polyurethane takes hours to dry. Since lacquer dries fast, it makes it easy to apply many coats.
Polyurethane is durable compared to lacquer. This is because of the thickness that allows it to leave a strong and durable coating.
Lacquer is thin and when applied is absorbed into the wood surface. Although it is also durable, it is susceptible to discoloration and peeling after some time.
Frequently Asked Questions
What Does Lacquer Do to Wood?
Lacquer is a wood finish that is used on high-end furniture. It is applied to wood to provide a smooth and glossy look.
The product is thin and therefore requires to be applied several times to achieve the desired look. One needs a sprayer to apply it. It is also fast drying and therefore applying multiple coats is easy.
Does Lacquer Scratch Easily?
Although lacquer is durable, it is susceptible to scratches and peeling. However, it is not difficult to repair the scratches with the application of new lacquer but the problem comes in when you are supposed to match the new sheen to the rest of the parts.
It is normally recommended that if there is a scratch, you do the entire wood and spray it all over again.
Does Lacquer Make Wood Waterproof?
Lacquer, like varnish and polyurethane, is a sealant with good waterproofing properties. This product is sprayed on clean and sanded wood and given some time to dry.
The best lacquer to use is the mixture of dissolved tree resin and sometimes synthetic resin in alcohol.
Can I Put Lacquer Over Paint?
There are risks associated with spraying solvent lacquer on the existing paint. Application of wet lacquer can result in paints and finishes wrinkling.
However, it is possible to avoid this problem by spraying light coats before applying wet coats. Alternatively, you can apply shellac before spraying the lacquer.
What Happens If You Don’t Sand Between Coats of Polyurethane?
There is no significant impact if you forget to put sand between coats. However, it is always recommended that you put sand between the coats when you apply polyurethane because this helps in increasing adhesion between layers thus giving more level finish.
But if you happen to have a short time and sanding takes a lot of time, then you can ignore this step and apply the product. Ensure that the layers are thin and they dry well before applying another layer.
For water-based polyurethane, six hours are enough for it to dry well as you apply the next coat. However, if you are using an oil-based product, this may take at least 24 hours to dry well before applying the next coat.
Can You Put Too Many Coats of Polyurethane?
Knowing the number of coats to apply is essential if you want to achieve good results. Most people would ask whether one polyurethane is enough. It is recommended that you apply multiple coats to protect the underlying wood.
Oil-based finishes need fewer layers than water-based type. This is because the water-based polyurethane is thin. You can apply about five coats for better results.
Since the oil-based is thick, it is important to be consistent with the coating to offer results. Usually, about 3 to 4 coats will do. The number of coats you apply entirely depends on the level of protection you are looking for.
Is 2 Coats of Polyurethane Enough?
Oil-based finishes are strong, and resistant to influences. The finish is thick and therefore influences the number of coats you can add.
However, the question of whether two coats are enough is of great concern to many people. If you are looking for ideal results, it is best if you apply about three to four coats.
Also, since this product takes a lot of time to dry out, you will be sure of waiting for a long time before you complete the project.
How Do You Apply Polyurethane Without Brush Marks?
Polyurethane normally leaves brush marks if you are using a paintbrush and it is for the first time. However, if it is consistently used and proper procedures are followed, these marks resolve themselves and polyurethane can bring out a smooth finish.
If these brush marks do not resolve, you can apply the following corrective mechanisms:
- Step 1
Instead of using the normal paintbrush, use a foam brush or a lambswool applicator. These two tools cannot leave marks.
- Step 2
Instead of the normal paintbrush, use a natural bristle brush. The natural bristle brushes are ideal if it comes to oil-based paints and they leave only a few marks compared to the synthetic brush.
- Step 3
Before you start applying polyurethane, thin it with paint thinner, and mix it with a paint stir stick. When the polyurethane is thick, the brush marks hold their shape. When you are thinning, polyurethane gives a smooth finished surface.
You can use different paint thinners and figure out which works best for you. Most constructors and homeowners apply an equal amount of thinner and polyurethane in the mixture but less thinner is recommended.
- Step 4
When you are using an applicator, refrain from moving it back and forth quickly as you apply the polyurethane.
This is because if you do this, it creates bubbles in the applied product and causes the product to dry fast giving the brush marks less time to dry out and level out naturally.
- Step 5
Sand the dried surface and let it dry overnight. Sanding the next day with sandpaper is fine. After that, keep applying multiple coats of polyurethane ensuring that you sand between each coat.
After you are through applying the final coat, sand it with 600 grit sandpaper for a smooth and glossy look.
Can I Put Lacquer Over Polyurethane?
Lacquer cannot be applied over polyurethane because they are not compatible unless a sealant is used. The best sealers to apply are shellac sealers and this can be applied by brush, spray, or rag.
Lacquer is not good with polyurethane because in cases where polyurethane is completely dried, it can react with it and destroy the finish.
In summary, both lacquer and polyurethane are good finishes and this is seen from how most people have embraced them. Although these two types are commonly confused and used interchangeably, the truth is the two products are totally different.
Lacquer is thin and requires that you apply it several times before you achieve your desired results.
Polyurethane, on the other hand, is thicker which makes it hard to apply with a sprayer but a brush can make a great job. All in all, both products can provide ideal results for your woodwork.