For anyone in search of a clear finish over furniture, varnish and lacquer will surely be at the top of their list. But what’s the difference between these finishes?
The main difference between varnish and shellac is that varnish is a synthetic finish gotten by mixing resins, driers, and thinning compounds. Shellac on the other hand is a natural finish gotten from the secretion of lac bugs.
The synthetic formula of varnish makes it much harder than shellac. But shellac offers better moisture resistance as its particles are naturally bonded.
However, you should know that shellac only becomes fully water-resistant after it has cured. This is because dried shellac will still dissolve in alcohol (or solvent). Varnish on the other hand cures as it dries so it becomes moisture-resistant much quicker than shellac.
What is Varnish?
Varnish is a wood finish gotten from the combination of solvents, oil driers, and resinous compounds. Combining all these compounds in a paint thinner creates a strong and durable finish known as varnish.
You should know that there are different types of varnish. The list includes polyurethane varnish, acrylic varnish, exterior varnish, and so on. Each type of varnish has a unique set of features but all types of varnish are similar in several ways.
For starters, all types of varnish offer good wood protection. When varnish is applied, it dries and cures to create a thick shiny layer on the wood. This layer due to its compact structure becomes water-resistant and hard enough to withstand dents and scratches.
The hard finish of varnish can also be used on other wood stains to make the stain last longer. This is because varnish doesn’t penetrate wood deeply so an existing stain will not stop the varnish from sticking. You should know that light sanding is usually needed before applying varnish.
What is Varnish Used For?
- Varnish is used to protect wood stains and paints
- Varnish protects wood from dents, moisture, and pest damage
- A coat of varnish on wood makes the wood moisture-resistant
- Varnish is used to reveal the wood grain
- Exterior varnish protects outdoor wood from UV rays and heat
Now that we have covered varnish, let’s dig into shellac.
What is Shellac?
Shellac is one of a few natural clear coats used in finishing wood. Shellac is gotten from the secretion of an insect. The lac bug secretes a natural resin called lac. This resin is collected and processed to create a shellac wood finish.
One major feature of this finish is its moisture resistance. Shellac offers impressive moisture resistance. So much that shellac is used in making stain-blocking primers. However, shellac only becomes fully moisture-resistant after the coat has cured.
When shellac dries, it should not be wiped with a solvent or alcohol as the coat will dissolve readily when exposed to a solvent. You would need to wait for the shellac to cure before it becomes fully resistant to moisture.
You should know that though shellac can be safely recoated in about 6 hours, it takes about 3 days for the shellac to fully cure and become moisture resistant. When shellac has fully cured, it can withstand moisture over 4 hours.
What is Shellac Used For?
- Shellac is used to make wood moisture-resistant
- Shellac can be used over non-wood items
- Being a light finish, shellac is used to reveal the wood grain
- Shellac is used over finished wood especially before another finish is applied. Painters do this to prevent bleed through.
So is varnish better than lacquer? Let’s compare both finishes to see which is superior.
Varnish vs Shellac
To compare varnish and lacquer, we’ll use the features of their finishes.
Here is a table that identifies the major differences between shellac and varnish:
|Thickness||Shellac is thin||Varnish is thicker than shellac|
|Durability||Good (up to 5 years)||Great (Up to 10 years)|
|Coats Required||4-5 coats on wood||2 coats are usually enough on wood|
|Paint Application||Easy (beginner level)||Average (requires some experience)|
|Indoor or outdoor use?||Shellac is suited to indoor furniture||Varnish will thrive on outdoor wood.|
Now, let’s check out these differences in detail.
Varnish contains synthetic compounds in its formula. Resins, solvents, oils, driers, and additives are all included in the make-up of varnish. These compounds give varnish superior qualities but they also give the finish an artificial formula.
Shellac however doesn’t contain these solvents or additives. Shellac is gotten from a natural source (insect secretion). As such, shellac is a natural resin meaning that the finish has a natural formula.
Varnish protects wood better than shellac. The hard varnish coating that dries on wood helps to protect the wood from scratches, dents, and blemishes.
You should also know that varnish contains additives and resins that reinforce the finish. These additives make the varnish harder and more protective of the wood underneath. Since shellac contains few additives, the finish isn’t as strong.
There is hardly any type of finish in the woodworking world that offers superior moisture resistance to shellac. Shellac offers better moisture resistance to wood. But, you should know that shellac only becomes moisture-resistant after the paint has cured and this can take several hours.
Varnish however cures as it dries. So varnish will become water-resistant quicker than shellac but the moisture resistance of varnish is inferior to shellac’s. You should also know that varnish retains its moisture resistance longer than shellac.
Varnish lasts longer than shellac. One reason for this is the superior finish that varnish gives. Since varnish is hard, moisture-resistant, and weather-resistant, it outlasts shellac by a few years.
At best, shellac wood finish will last about 5-6 years but varnish can last up to 10 years if applied and maintained properly. You should know that both finishes last longer when used on indoor wood and furniture.
Purpose and Usage
Varnish is used for two main things. The first is to cover wood stains and paint on wood. The second function is to cover bare wood. Both of these functions fall under protection. So in a way, varnish is only used to protect wood or the finish underneath.
Shellac however is more universal. Shellac can be used to protect wood and wood stains. Shellac can also be used to block moisture and stains from bleeding through. The finish also serves as a good primer paint. So the uses of shellac are more than the uses of varnish.
Verdict: Shellac has an all-around use while varnish is suited to wood and stain protection.
Generally, pure and natural finishes like shellac cost more than synthetic finishes like varnish.
Level of Thickness
Varnish is heavier and thicker than shellac. This is because varnish has a high solid ratio due to the numerous compounds and resins in its formula.
These extra ingredients make varnish coats heavier and thicker. Shellac however is lighter than varnish since the finish has more natural than artificial compounds.
It’s more difficult to apply varnish than shellac. This is because varnish is thicker and heavier than shellac. As such, varnish will be difficult to control and apply. The thick nature of varnish also means that the finish will reveal brush marks and imperfections when the finish gets dry.
This is why you need some level of experience while applying varnish. You can make varnish application easier by thinning the paint with mineral spirits before applying it. This makes the varnish easier to control, lift, and apply.
Shellac is easier to apply since it’s not as thick as varnish. However, you’ll need more coats of shellac given its nature. 4 to 5 coats of shellac are usually needed for proper coverage on wood. For varnish, one coat can be enough depending on the type of wood.
Indoor or Outdoor Use?
Shellac is suited to indoor use. Shellac is commonly used on kitchen cabinets, drawers, antiques, and tabletops. These surfaces are lightly used and they don’t carry weight or get walked on frequently. So a few coats of varnish will offer great protection.
Since varnish offers better wood protection and weather resistance, it is more suited to exterior use. Exterior varnish for instance is known to offer UV resistance in addition to being moisture-resistant and hard. So it will thrive on outdoor wood.
Do You Need Shellac or Varnish?
Here are a few factors to consider while deciding between varnish and lacquer:
The Price Tag
Natural finishes like shellac cost more than varnish because natural finishes are harder to process and preserve. Also, since shellac has more uses than varnish, it is usually a bit costlier. So varnish will be a pocket-friendly option if you are on a tight budget.
Shellac offers better moisture resistance when the finish has fully cured. If you want a finish over wood to stop stains and moisture from bleeding through or affecting the wood, shellac is a good choice.
To protect the wood from scratches, dents, and other types of wood damage, varnish is a top choice. The strong finish of varnish means that it protects wood properly.
Varnish lasts longer than shellac so it’s ideal for surfaces that you want to protect long term.
If you want a finish for your kitchen equipment, the finish has to be food-safe. Shellac is considered food safe since it doesn’t contain any synthetic resin. Varnish shouldn’t be used near food items as it can be toxic.
Overall, shellac and varnish are great finishes. Ultimately, the choice you make depends on your taste and needs. Remember, varnish is harder and more suited to outdoor wood than shellac.
Also, since shellac is natural and pure, it is considered food safe and can be used on kitchen equipment. Varnish has a more synthetic and toxic makeup. So it’s not food safe.