Shellac is a durable wood finish which has been used extensively for hardwood flooring and furniture up before the 1920’s when it was replaced by nitrocellulose lacquer, which dries faster. Shellac is still used on specialty items plus a few hardwood flooring. Shellac is derived in the insect and chosen as dry flakes. The flakes are dissolved into denatured alcohol to form liquid shellac that is applied with a brush or spray gun. Shellac is easy to remove with chemical strippers.
Rubber gloves and safety glasses are recommended, as chemical strippers are very poisonous and can burn skin on contact. Apply a thick coat of stripper on the surface of the shellac with a brush, or put a little bit of the stripper right on the surface and then spread it out with a brush or stick. Allow the stripper remain on the surface of the shellac for 10 minutes.
The stripper responds to oxygen and will quickly break down and reactivate the original program of shellac. Scrape the gelled shellac into small gobs from the center to the border where they can drop off the side of this timber. It’s also sensible to have a drop cloth under the timber to catch the gobs. Scrape the gelled shellac to a dust pan and then empty it into a can. Add more stripper and wait patiently till the shellac is dissolved sufficient to scratch whether the shellac is not gelled satisfactorily.
Scrape the surface of the timber in all directions until the bulk of the shellac has been gone. Scrape over the timber one more time parallel with the grain to remove the final traces of gelled shellac, and if you happened to miss any tiny traces of shellac, parallel lines won’t be noticeable. Be extremely cautious when scratching off shellac. Utilizing a flexible scratching blade on an oscillating tool works nicely for this task, but use caution since scrapers can scratch or gouge timber if used improperly.
Resanding and Planning
Sand the wood lightly, moving parallel to the grain to prevent cross-grain scratching. Over time, wood will bleach or darken based on light exposure. Shellac makes timber turn a light-amber colour. Sanding it will return the timber to its original colour. In addition, sanding will remove any light scratches which may have happened when you scraped the shellac. Sand the wood once with a medium grit, then sand the wood with a light-grade. This will prepare the wood for a fresh top coat.