Maintaining A Shellac Finish
The primary consideration for maintaining a shellac finish is that temperature control must be maintained. Aside from that, a shellac finish can be cleaned or retouched at will, without fear of compromising the finish or causing water stains. This article will offer some key pointers on how to maintain a shellac finish, and how to avoid the few possible problems that you are likely to encounter.
The Versatility of Shellac
As a wall primer, shellac is one of the most dependable coatings. It has unique properties that allow it to bond to all types of materials. Compared to other types of sealant, shellac is tolerant to all but the harshest chemicals, and is resistant to stains and scratches, making it excellent as a finish for furniture and other natural wood applications.
Shellac Is Waterproof
Shellac is waterproof. Over time, however, the resistance to moisture declines, perhaps due to accumulated moisture. To prevent this, it is advised that a furniture sealer such as Murphy's Oil is applied at least twice a year. Additional coats of shellac can be added periodically, but doing so reduces any antique value the item may have had. Unless new repairs make it a necessity, it is very rare for shellac to need to be removed and reapplied. Some causes for doing so include proximity to high heat, severe water damage, and exposure to harsh chemicals.
Shellac Has a Low Heat Threshold
Shellac does not stand up well to high heat. At temperatures as low as 120 degrees Fahrenheit, shellac may begin cracking, and by 130 degrees, the finish will begin flaking. This makes shellac less suitable for the extreme southern and southwestern United States, due to a reduced durability. In actuality, shellac is used all over the world, and in every temperate zone, but it lasts longer in some areas than others. Since continuous 120 degree heat is rare and equally harmful to living things, this heat threshold tends to be ignored by people who use shellac finishes.
Shellac Can Be Retouched
If you insist on touching up the shellac finish on a piece of furniture, use a piece of 220 grit sandpaper, and very lightly sand all exposed surfaces. This creates tiny grooves and pits that the shellac will be able to bind with. When the sanding is complete, wipe down the surface with a damp cloth.
Shellac Cleans Easily
Shellac is cleaned using a damp cloth and light cleaning agents, such as ordinary dish soap, or even anti-bacterial soaps. It takes furniture polish, but should not be directly exposed to standing water or the finish is likely to cloud or stain. For all practical purposes, shellac does not require any special care or maintenance. Part of its very beauty is the simple elegance and lack of upkeep.
Shellac Is Chemically Sensitive
Because of the sensitivity of shellac to harsh chemicals, it is important that you never try to clean a shellac finish with anything stronger than a mild dish detergent. Bleach, ammonia, and other household chemical will leave stains or water spots, and some chemicals will do far worse, actually destroying the finish you are trying to preserve.