Removing Powercoat From Pan: Easy And Effective Methods

Powder coating is a popular method of adding a protective layer to metal surfaces. It is well-known for its durability and strong adhesion to the underlying material. While it is an excellent way to protect metal from damage, corrosion, and abrasion, there may be times when you need to remove it, such as for repairs, restoration, or a change in design. Removing powder coating can be challenging due to its strong adhesion, but several methods can effectively strip it off without damaging the underlying material. This includes chemical stripping, thermal stripping, abrasive blasting (sandblasting or media blasting), and laser removal. Each method has its advantages and disadvantages, and some are more suitable for industrial applications due to specialized equipment requirements.

Chemical stripping

Advantages of Chemical Stripping

Disadvantages of Chemical Stripping

Chemical strippers are toxic and hazardous. They can burn your skin if you do not wear a respirator, goggles, and long gloves. The strippers are also difficult to clean up and dispose of. The chemical stripper, the water used to clean the surface, and any contaminated items must be taken to a waste disposal centre.

How to Use a Chemical Stripper

When using a chemical stripper, work in a well-ventilated area and wear protective gear, including gloves, safety goggles, and a respirator mask. Lay a tarp or plastic sheet over your workspace to protect it from the chemical stripper. Simply spray the chemical stripper on top of the powder coating and wait 5 to 10 minutes. Then, scrape away the coating with a plastic scrub brush or toothbrush. Reapply the stripper as needed, then rinse off the surface in a bucket of water.

Thermal stripping

The process involves heating the powder coat to a minimum of 650°F, which causes it to lose adhesion or even combust. This requires the use of an industrial oven, and the burn-off of the powder coat emits dangerous volatile organic compounds (VOCs) that need to be properly ventilated. There are various methods that range in temperature from 650°F to 1,200°F. The lowest temperature option would take several hours, while the most aggressive high-temperature method can burn off the powder coat in a matter of minutes.

There are also hybrid methods that combine heat with abrasives or chemicals to remove powder coating more efficiently. However, thermal stripping is not suitable for temperature-sensitive materials. Even aluminium would lose a significant portion of its strength at the minimum operating temperature of 650°F.

Before applying heat, it is important to use a wire brush to remove any loose or flaking coating to ensure optimal results and prevent issues. Additionally, it is crucial to prioritise safety when working with high temperatures. Wear gloves, goggles, and a face mask, and ensure proper ventilation to avoid accidents or environmental damage caused by waste disposal.

Abrasive blasting

• Prepare your work area: Select a well-ventilated space to work in and cover the surrounding surfaces with drop cloths or plastic sheets to avoid potential damage.
• Put on the appropriate safety gear: Wear protective clothing, gloves, goggles, and a face mask. Ensure you have proper ventilation while handling the materials.
• Choose the right abrasive media: Select an appropriate abrasive media for the type of metal you are working on. Some common options include glass or glass beads, aluminum oxide, garnet, steel grit, and coal slag.
• Set up your equipment: Fill the blasting pot or pressure vessel with the chosen abrasive media. Ensure your air compressor can deliver compressed air that is dry, cool, and free of oil and contaminants. Connect the blasting pot to the compressed air supply using piping that matches the size specified by the manufacturer.
• Adjust the blast pot: With the help of an assistant, adjust the media feed at the bottom of the pot while triggering the nozzle. The media should be barely visible coming out of the nozzle to prevent clogging and achieve optimal results.
• Aim the nozzle: Hold the nozzle about 6 inches (15 cm) away from the coated surface and move it back and forth to strip the powder coating.
• Clean the surface: After removing the powder coating, thoroughly clean the metal surface with a degreaser or cleaning solution to eliminate any remaining residue.

Sandblasting

Step 1: Prepare your work area and gather essential tools

Prioritise safety when removing powder coating from metal. Working with sandblasting equipment and high-velocity particles can be dangerous. Ensure you have adequate ventilation and wear protective clothing, including gloves, goggles, and a face mask. Cover the surrounding area with drop cloths or plastic sheets to avoid damage.

Step 2: Choose the appropriate abrasive material

Several abrasive materials can be used for sandblasting, including sand, glass beads, aluminum oxide, steel grit, garnet, and more. Consider the desired surface finish, compatibility with the coating's chemistry, and the type of equipment available.

Step 3: Set up your sandblaster

Fill the sandblaster with the chosen abrasive material. Attach the air compressor hose to the sandblaster. Ensure the compressor has sufficient power for sandblasting, typically requiring at least a 2-horsepower motor.

Step 4: Perform the sandblasting

Aim the nozzle of the sandblaster about 6 inches (15 cm) away from the coated surface. Move the nozzle back and forth in a steady motion to strip the powder coating. The size of your project will determine how long the sandblasting takes. For example, a wheel rim might take 1 to 2 hours, while a whole car can take several days.

Step 5: Clean and prepare the surface for refinishing (if desired)

After removing the powder coating, you may need to clean and prepare the surface for refinishing. Use a degreaser or cleaning solution to eliminate any stubborn residue. If you plan to apply a new layer of powder coating, follow the manufacturer's guidelines for surface preparation, application, and curing.

Laser removal

Pros

• Lasers cause very little damage. They are less likely to damage softer metals compared to other methods like abrasive blasting or burn-off ovens.
• Lasers are more environmentally friendly than some other methods as they don't use hazardous materials and require less cleanup.
• Lasers are very precise and can strip powder from a small area, but they can also be used for large surfaces.
• They can be used on almost any material since they don't alter the substrate underneath the powder coating.

Cons

• Lasers are very expensive. The devices themselves can cost upwards of $10,000 and they typically cost about $3-$4 per square foot of material cleaned.
• Lasers usually smooth out the surface after removing the powder coating, so the surface may need to be scuffed up again before applying a new coat of paint or powder coating.

Overall, laser removal is a highly effective method for removing powder coating, especially for temperature-sensitive materials. However, it is a costly option and may not be suitable for those on a budget.

Frequently asked questions