Paints and finishes on furniture deteriorate as they age. This can make them look bad and, more importantly, ineffective at protecting the wood beneath from moisture. In the case of deteriorated finishes, it is best to remove them and replace them with new finishes. Paint, on the other hand, can often be cleaned and painted over. There are two ways to remove an old finish from furniture: sanding it off or stripping it off. However, heat guns should not be used on furniture as the heat can cause veneer to delaminate or scorch the wood.
Using a Stripper
The most effective way to remove an old finish or paint without sanding is with a paint-and-varnish remover, also known as a “stripper” or “paint stripper.” While messy, it is the best method. Paint strippers consist of solvents strong enough to penetrate a paint or finish film, which acts on the film in one of three ways, depending on what is being stripped.
- They dissolve the film into a gunk that can be wiped off.
- They swell the film so it blisters and can be scraped off.
- They break the bond of the film to the wood so the film can be lifted off in sheets with a putty knife.
Most old finishes such as shellac and lacquer dissolve, while paint and varnish swell and blister. High-performance finishes used on office furniture and kitchen cabinets during the last 40 years can also lift off in sheets when paint stripper is applied.
How Strippers Work
Paint strippers consist of a solvent or combination of solvents strong enough to penetrate a paint or finish film. These solvents act on the film in one of three ways depending on what is being stripped:
- They dissolve the film into a gunk that can be wiped off.
- They swell the film so it blisters and can be scraped off.
- They break the bond of the film to the wood so the film can be lifted off in sheets with a putty knife.
Most old finishes (shellac and lacquer) dissolve, while paint and varnish swell and blister. Many newer high-performance finishes hold together but lose their attachment to the wood. High-performance finishes, often used on office furniture and kitchen cabinets during the last 40 years, lift off in sheets when a paint stripper is applied.
Choosing a Paint Stripper
There are four categories of paint strippers, each with its own strengths and weaknesses.
- The strongest and fastest-acting stripping solvent is methylene chloride (MC). It is also non-flammable and noticeably heavier than other strippers.
- The next in order of strength and speed are strippers with some methylene chloride combined with a number of other solvents. These strippers are flammable.
- The third in line for strength and speed are strippers that contain a number of solvents similar to those in weak MC but no methylene chloride. These strippers are flammable and don’t have methylene chloride listed as an ingredient.
- The fourth category of paint stripper is n-methyl pyrrolidone (NMP). It evaporates very slowly and is the most expensive of all the solvents used.
Conclusion
Removing an old finish or paint from furniture can be a daunting task, but using the right tools and techniques can make the job easier and safer. Remember, stripping is usually the best method of removing an old finish, and using a paint-and-varnish remover is the best way to do it. Also, it’s important to choose the right type of paint stripper for the job and to follow safety precautions to avoid any hazards.
By taking the time to properly strip and refinish old furniture, you can restore it to its former glory and extend its life for many years to come. And with the right tools and techniques, you can do it yourself, without having to hire a professional. So go ahead and give it a try!
