Should You Sand Between Coats of Shellac


sander on a workbench

Putting the finishing touches on a build can be exciting work, even if it is time-consuming. When it comes to many lacquers, this finishing process can involve a lot of sanding, which many can find to be miserable work. So, without short-selling yourself and your project, exactly how much sanding do you need to do?

You should always lightly sand in between coats of shellac with sandpaper in the range of 320 to 400. Doing this helps the next coat to stick on better, and it also removes any flaws that may have been created in the application process. This ensures that small flaws don’t compound over time.

Yes, that means more sanding. I promise that it’s all worth it, even if it is monotonous. That being said, there’s a lot that you can do to finish this project up absolutely perfectly, so let’s explore everything that shellac can offer as a finisher.

The huge variety of finishes for furniture is one of the subjects we will be diving deeply into during our live online workshops at Cucamonga Woodworking and you can check out our past workshop YouTube videos Here(Link to Cucamonga Woodworking)

Sanding Between Coats Of Shellac

First off, sanding in between coats of a product is not something that’s unique to shellac. All kinds of lacquer go on a lot better if you lightly sand it between each coat. When it comes to finishers like these, it is important to remember that the layers that you apply don’t need to be very thick at all, meaning that sanding a little bit of the top of each layer won’t be a problem.

Shellac is definitely like that. Shellac should be applied in several thin coats, all of which need to be sanded before the next coat is added.

The sanding part of the process makes everything look just so much nicer in the end. Sanding each layer as you go prevents little flaws from building up over a number of layers and prevents ugly blemishes. It also helps the wood become smooth, and prevents people from getting splinters when they come into contact with the wood.

It also helps the wood really absorb the finish, as Shellac really tends to seal the wood up when it is dry if it isn’t sanded at least a little bit.

It’s also important to remember, however, that you can definitely overdo it with the sanding. Sanding the shellac too heavily could accidentally remove it, or it could cause ugly burns on the surface of the wood. That’s why it’s important not to use sandpaper that’s too strong or to sand too heavily.

320 to 400 grit sandpaper is generally a great grit type to use for the middle layers of the shellac. For the first layer, you may want to sand even lighter to avoid hurting the wood underneath, so somewhere between a 180 to 220 grit will be optimal.

This is also true of the final layer of shellac that you add. A lot of places online will tell you not to sand that final layer at all, and honestly, if you choose not to it won’t ruin your project, but very lightly sanding that last layer of shellac with 180 to 220 grit sandpaper will make the end product quite a bit better, especially after it’s all been polished.

Rubbing out this final layer can also be beneficial, whether you sand it or not.

What Is Shellac?

Let’s take a quick detour and talk about where shellac actually comes from. You came to this article, so you definitely already know what shellac is for, but the question of how it is made might be relevant to how you decide to treat it.

Shellac is a natural finisher made from the resin secreted by female lac bugs in India. This resin is scraped off of the trees where the bugs live, and then it is then melted down to separated the bark and insects from the actual shellac itself.

This sheet of pure shellac is then dried in a sheet to make little chips, which can be dissolved in alcohol to make the liquid shellac solution which is usually used as a wood finisher. Shellac can come in a variety of colors, which makes it a versatile finisher.

Now, you may be wondering why there are so many different colors available if shellac is produced by a bug. The answer is simple. “The color is influenced by the sap of the tree the lac bug is living on and by the time of harvest. Historically, the most commonly sold shellac is called ‘orange shellac’.” source The “orange shellac” is the color most commonly found on wood appliances from the 19th century.

This kind of shellac tends to go bad after about a year, so make sure to check the mixing date on any shellac you buy (or any shellac you plan to use from your work cabinet) to make sure that it’s still good.

“Shellac functions as a tough natural primer, sanding sealant, tannin-blocker, odor-blocker, stain, and high-gloss varnish. Shellac was once used in electrical applications as it possesses good insulation qualities and it seals out moisture.” source

Dry shellac can also be melted and used to add a coating to things. Because liquid shellac is better at covering more area and doesn’t need to be melted before use, it generally beats straight shellac chips when it comes to using it as a wood finisher.

Shellac is technically edible, but the alcohol used in liquid shellac is definitely the kind that will make you go blind if you drink it so… that’s some information for you. I do not advise that you drink it, and make sure that you keep it out of reach of small children. They may think that it is a tasty drink because of the dark amber color, similar to many soft drinks. I advise you to keep it on a high shelf in your garage, so it does not accidentally get knocked over by children. If it’s left open for too long, the harsh smell could cause headaches and nausea that will affect you or your family. Avoid the fumes of strong products like this!

Shellac is often used in the place of wax when coating foods to make them more appetizing, so make sure to wash all produce that you purchase before consumption.

Shellac replaced oil and wax finishes in the 19th century, but was soon replaced as the most popular finish to use in the 1920’s and ’30’s by nitrocellulose lacquer. source

At our Cucamonga Woodworking live online workshops we discuss bend and steaming wood at about the 5 minute mark of this video. You can also check out our other past workshops on Youtube Here(Link to Cucamonga Woodworking)

Applying Shellac To Wood

There are two main ways of applying shellac to wood. The first is to brush it on using a soft brush with Chinese-style bristles. You can find these brushes at any hardware store or paint store for a relatively low price. This is the easier of the two methods, although you still have to be careful as shellac starts drying as soon as you start to apply it. This means that you can’t just brush over any lumps or drips that you produce.

You’ll want to use long, continuous brush strokes along the grain of the wood in order to make sure that the coating is thin enough. You may even want to go over the painted-on shellac with a muslin cloth to smooth it out a little bit and get rid of any excess product that may make the wood look uneven in color.

Padding is the other way that you can apply shellac, and of the two it is definitely the more involved. First, you load the liquid shellac into an old sock (with no holes in it. That’s a critical part.) The sock will act as a reservoir, allowing you to not have to worry about dipping your cloth every couple of seconds.

Wrap the part of the sock with the shellac inside in muslin, then slowly and gently ease it on and off of the surface that you are putting the finish on. Be careful not to rub the muslin onto the surface or to push too heavily on it, as these can cause flaws in the finish of the wood.

You’ll also want to make sure that you don’t just go with the grain, but that you make use of a gentle irregular pattern.

If things start sticking in a way that makes work difficult, you can always apply some mineral oil to the sock to lubricate it. However, do not put more than a few drops into the shellac, because the oil will dilute the product, and may separate if you put in too much. This will cause the wood you are finishing to have oil spots, which never looks good.

Don’t worry about getting thick layers on when applying shellac. Shellac works best when applied a tiny bit at a time.

Once you’ve finished the first coat, you’ll need to wait for it to dry. This should take at least two hours, so have a plan to be doing something else during that time. It isn’t quite long enough to watch The Fellowship of the Ring again, but The Empire Strikes Back is almost exactly two hours long, so if you put that on as soon as you’re done with the application, the credits should roll just in time for you to start work again. You can also work on other projects during that time, or just take the time to relax a little bit.

Once you’ve finished with your Star Wars movie of choice (they’re all about two hours long) it’s time to lightly sand down the coat of shellac that you left to dry. 320 grit will pretty much always be enough, and you should remember that your goal is to ensure the next coat goes on well and to weed out impurities.

When that’s finished, let it rest for another two hours before putting on the next coat. Come to think of it, this would be a great time for a Star Wars marathon.

You should repeat this cycle for four coats. When you get to the last coat it’s time to rube the shellac out.

Rubbing out is basically the process of lightly sanding the shellac and then drying it. For this, you’ll need that lighter sandpaper we talked about earlier. You’ll need to let it cure for two or three days before you can rub it out, which means that now is the time for that Lord of the Rings marathon.

Rubbing out is extremely important, as it deals with the very last coat of finish. This is the layer that will be the most easily visible when the project is done.

When the shellac has been fully rubbed out, you can start polishing it. There are a couple of different methods that you can use to polish shellac. French polishing is fairly involved but yields a very shiny finish, while if you want the shellac a bit more glossy you should just buff it out with some steel wool and wax.

How To Get Shellac

Shellac is very commonly used in woodworking, especially when it comes to furniture. Because of this, you can buy it at pretty much any hardware store. You can also buy it on Amazon or directly from any number of shellac producers in the United States.

When ordering shellac, it’s important to make sure that you’re buying shellac for use on wood, and not for use on nails or candy. It’s not like wood shellac is special or anything, it’s just that you might accidentally get dry shellac or order a quantity that’s too small if you get the wrong kind.

This is really only a problem when ordering online, as you can generally see what kind of shellac you’re getting before you buy it if you’re shopping in person. However, shellac is very easy to find in local hardware stores.

Cost and Color of Shellac

Shellac is a relatively low-cost finishing product for your wood project. Cans of shellac range in price from $10-$60, depending on the size of the can. However, unless you are completing a large wood project, like an outdoor deck, you will not need to purchase the large can.

Although most shellac that is purchased is a dark, amber color, there are many different colors available. The colors range “from a very light blonde to a very dark brown, with many varieties of brown, yellow, orange and red in between.” source

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