Shellac is a resin derived from the secretion of a group of hemiptera insects from the coccidia family. If processed, it forms waxy particles which are then dissolved in industrial alcohol to brass the liquid shellac. Due to its characteristics of hardness, brilliance and solubility, it is used, as well as for the preparation of sealing wax, in the production of paints, as a primer and as an ingredient in mastics. This article explains how to remove shellac used primarily as a finish for wood or as a sealant.
Steps
Method 1 of 4: Check that the wood finish is shellac
Step 1. Find out how old the wood or furniture is
Shellac was a very common wood finish prior to 1920, and knowing that the wood is prior to that date may be enough to indicate the presence of a shellac finish. Shellac is also the main ingredient in French polish and has been used for this purpose on quality furniture over the last century.
Step 2. Check the finish
Whether they are old or new, here is the way to check the finish of the furniture or wood:
- Dab a section of the wood paneling with a cotton swab dipped in denatured alcohol. Try to do this in an inconspicuous spot.
- If it is shellac finish, it will liquefy and melt.
- If the finish feels soft but does not melt, it means that shellac is present in the coating but has been mixed with other types of lacquer.
- If you get any other type of reaction it is probably a different finish. If in doubt, consult a furniture restoration expert.
Method 2 of 4: Decide if the shellac really needs to be removed
Step 1. Always try to improve the situation and not make it worse, especially in furniture restoration and woodworking
If the shellac finish looks smudged or just plain dirty, try one of these methods:
- Clean the surface using an abrasive material such as pumice stone or sandpaper.
- Remove any stains or dirt.
- Rub with a cloth.
Step 2. Wipe with a clean cloth
If the surface looks smooth again, you've saved yourself the work of removing shellac.
Method 3 of 4: Apply denatured alcohol to shellac
For deeper, uneven stains or missing parts in the finish, removing shellac is probably the best choice. Here's how to do it:
Step 1. Use rubbing alcohol to remove shellac
You will also need a steel abrasive sponge.
Step 2. Coat the surface with a brush dipped in denatured alcohol
Step 3. Let the alcohol soak in for a few minutes, this way the shellac will begin to come off on its own
Method 4 of 4: Remove the shellac
Step 1. Put on a pair of rubber gloves to protect your hands
Step 2. Scrub the shellac with a steel sponge trying to completely remove the shellac
This operation requires some effort and intense rubbing. You may need to take breaks and then start over, also depending on the size of the job. Having outside help is always a good solution
Step 3. For curved, grooved or more difficult areas, use a utility knife
This will be able to reach the narrowest parts where the sponge cannot reach.
Step 4. Remove the rest of the shellac by wiping with a rag
Change the rag frequently to avoid reapplying shellac that has already been removed from the surface.
Step 5. Remove any residue and debris before proceeding with adding a new finish
It is important to sand the surface before applying new protection.
Advice
- Special products are available for removing shellac. Decide if you should buy a professional product by getting advice from the retailer or manufacturer.
- Shellac is available in a wide range of colors - in wick varnish the color is golden-brown and the best quality shellac is used; in the classic French polishing there is an orange undertone, while the lightened shellac is used for pale colored woods and the transparent one is obtained by removing the wax from the lightened shellac.
Warnings
- You may need to reapply the denatured alcohol several times as it will dry very quickly.
- Although it is a natural material, some finishes can be difficult to remove. This may be due to a combination of factors such as age, method of application, and other layers of different material. If after a couple of attempts you do not see results, seek professional advice.
- If you wish to reapply a new shellac finish, you need to be aware that it will be very easy to scratch and will be susceptible to water and alcohol damage. You also need to be very skilled in applying and polishing.
