Removing old furniture finish primarily involves sanding and/or using chemical strippers, which are effective methods for revealing the natural wood underneath. The best approach often depends on the type of finish, the wood, and the age and value of the furniture piece, with older items requiring extra care to protect their integrity.
Understanding Your Furniture Piece
Before you begin, it's crucial to assess the furniture. This assessment helps you choose the most appropriate and least damaging removal method.
- Age and Material: If you're working on an old piece, it actually needs a greater amount of protection than a newer piece. Older furniture may have delicate veneers or historically significant finishes that require gentle handling. Identify if the wood is solid, veneered, soft (like pine), or hard (like oak). Veneers are very thin and can be easily damaged by aggressive sanding.
- Type of Finish: Is it varnish, shellac, lacquer, polyurethane, or paint? Different finishes react differently to strippers and sanding. For instance, shellac is alcohol-soluble, making it easier to remove with denatured alcohol than with harsh chemical strippers.
Method 1: Chemical Stripping
Chemical strippers dissolve or soften the finish, allowing it to be scraped away. They are particularly useful for intricate carvings, turned legs, or when you want to avoid altering the wood grain, which can happen with aggressive sanding.
Types of Chemical Strippers
- Methylene Chloride-based Strippers: These are highly effective and fast-acting but contain strong chemicals. They are excellent for tough finishes but require maximum ventilation and safety precautions.
- NMP (N-Methyl-2-pyrrolidone) based Strippers: A less volatile alternative to methylene chloride, these are still strong but generally work slower.
- Citrus or Soy-based Strippers: These are eco-friendlier and safer alternatives, made from natural ingredients. They are slower-acting but have a pleasant scent and are ideal for light finishes or when working indoors.
- Caustic (Lye-based) Strippers: Historically used, these are extremely harsh and can darken or damage certain woods, especially oak. Generally avoided for fine furniture.
Application Process
- Preparation: Place the furniture on a drop cloth in a well-ventilated area, preferably outdoors. Remove hardware like knobs and pulls.
- Application: Apply a thick, even layer of stripper with a natural-bristle brush (for solvent-based) or synthetic brush (for water-based), ensuring complete coverage.
- Dwell Time: Allow the stripper to work for the time recommended by the manufacturer. The finish will typically bubble or soften.
- Removal: Use a plastic or dull metal scraper to gently remove the softened finish. Work with the grain of the wood. For intricate areas, use an old toothbrush, stiff brush, or fine steel wool (grade #000).
- Neutralization/Cleaning: After scraping, clean the surface according to the stripper's instructions. This often involves wiping with mineral spirits, denatured alcohol, or water to remove residue. This step is crucial for proper adhesion of new finishes.
Safety First
Always wear chemical-resistant gloves, eye protection, and a respirator when using chemical strippers. Ensure adequate ventilation.
Method 2: Sanding
Sanding physically abrades the old finish off the wood. It's an effective method, especially for removing loose varnish.
When to Use Sanding
Sanding is ideal for flat, open surfaces and when you want to smooth out imperfections in the wood itself. It's often used in conjunction with chemical stripping, either before to remove loose layers or after to smooth the wood and remove any remaining finish residue.
Sanding Tools
- Hand Sanding: Essential for detailed areas, curves, and light touch-ups. Use sanding blocks to maintain flat surfaces.
- Orbital Sanders: Good for moderate-sized flat areas. They move in small circles, reducing swirl marks.
- Belt Sanders: To remove finishes quickly from larger areas, a belt sander can be very efficient. However, take care not to damage the piece by sanding too deeply, especially on veneers or softer woods, as they can quickly remove too much material.
- Detail Sanders: Excellent for corners and tight spaces that orbital or belt sanders can't reach.
Sandpaper Grit Progression
Start with a coarser grit to remove the finish and gradually move to finer grits to smooth the wood:
- 60-80 grit: For initial removal of heavy finishes or significant imperfections. Use with extreme caution.
- 100-120 grit: To remove remaining finish and scratch marks from coarser grits.
- 150-180 grit: For general smoothing before staining.
- 220 grit: For final smoothing before applying a new finish.
Important: Always sand with the grain of the wood to avoid unsightly scratch marks.
Preventing Damage
When sanding, especially on old or veneered pieces, be extremely careful not to sand through the veneer or create deep gouges. Sand lightly and check your progress frequently.
Method 3: Heat Guns (Alternative for Stubborn Finishes)
For very thick, stubborn finishes, particularly paint, a heat gun can soften the finish, making it easier to scrape off. Apply heat evenly in small sections, then scrape gently with a dull putty knife or scraper. Exercise extreme caution to avoid burning the wood or releasing toxic fumes from certain finishes (like lead paint). Always ventilate well and wear a respirator.
Essential Tools and Materials
Having the right equipment makes the job safer and more efficient.
| Tool/Material | Purpose |
|---|---|
| Chemical Strippers | Dissolving finishes |
| Sandpaper | Various grits (60-220) for removal and smoothing |
| Scrapers | Plastic or dull metal for removing softened finish |
| Safety Gear | Chemical-resistant gloves, eye protection, respirator |
| Brushes | For applying stripper, cleaning |
| Drop Cloths/Plastic | Protecting work area |
| Mineral Spirits/Denatured Alcohol | For cleaning stripper residue |
| Steel Wool | Fine grade (#0000) for intricate details with stripper |
| Sanding Blocks/Tools | Hand sanding, orbital sanders, belt sanders |
| Clean Rags | Wiping, cleaning |
Step-by-Step Guide to Finish Removal
- Prepare Your Workspace: Choose a well-ventilated area. Cover the floor and surrounding areas with plastic sheeting or drop cloths.
- Disassemble (if possible): Remove drawers, doors, and any hardware to make stripping easier and ensure thoroughness.
- Clean the Furniture: Wipe down the piece to remove dirt and grime.
- Choose Your Method: Decide whether to use chemical stripping, sanding, or a combination, based on your furniture assessment.
- Apply Stripper or Begin Sanding:
- Chemical Stripping: Follow manufacturer instructions carefully. Apply, let dwell, then scrape.
- Sanding: Start with a coarser grit (e.g., 100-120) and work your way up to finer grits (e.g., 220). Always sand with the wood grain.
- Clean Residue: After stripping, neutralize the surface as recommended by the stripper manufacturer. After sanding, vacuum or wipe down the piece to remove all dust.
- Inspect and Repeat: Check for any remaining finish. You may need to repeat stripping or sanding in certain areas.
- Final Sanding: Lightly hand-sand the entire piece with fine-grit sandpaper (220 grit) to achieve a smooth, uniform surface ready for a new finish.
Post-Stripping/Sanding Care
Once the old finish is completely removed, the wood is vulnerable. Apply a new finish (stain, oil, varnish, paint) promptly to protect it from moisture, dirt, and damage. Ensure the wood is completely dry and clean before applying any new coatings.
Safety Considerations
Safety should be your top priority. Always:
- Work in a well-ventilated area, preferably outdoors.
- Wear appropriate personal protective equipment (PPE), including chemical-resistant gloves, eye protection, and a respirator, especially when using chemical strippers or creating fine dust from sanding.
- Read and follow all product instructions and safety warnings.
- Dispose of chemicals and rags properly according to local regulations.
By carefully selecting the right method and taking proper precautions, you can successfully remove old furniture finish and prepare your piece for a beautiful new life.
