How to Remove Rust from Old Coca-Cola Machines

When restoring a vintage Coca-Cola machine, rust is often one of the most significant challenges you’ll face. Over time, exposure to moisture and the elements can cause metal parts to rust, damaging both the machine’s structure and its appearance. Removing rust is essential to preserving the integrity of the machine and preparing it for repainting or further restoration. This guide will walk you through the various methods of rust removal, including sandblasting, chemical rust converters, and electronic rust removal, helping you restore your Coke machine to its former glory.

Why Removing Rust is Important

Rust, or iron oxide, forms when metal is exposed to water and oxygen for an extended period. If left untreated, rust can lead to more severe corrosion, weakening the machine’s structure, and affecting its appearance. Removing rust not only improves the look of your machine but also ensures a clean, smooth surface for repainting, which can extend the life of your Coca-Cola machine for years to come.

Materials Needed for Rust Removal

Before you begin, make sure you have the right tools and materials:

  • Wire brush or steel wool (for light rust)
  • Power sander or angle grinder (for heavy rust)
  • Rust remover solution (Evapo-Rust, Rust-Oleum Rust Dissolver, or homemade solutions)
  • Rust converter (for treating remaining rust)
  • Sandpaper (various grits, from coarse to fine)
  • Plastic sheeting or drop cloth
  • Rags or microfiber towels
  • Chemical gloves and safety glasses
  • Protective respirator (if using strong chemicals or sandblasting)
  • Heat gun (optional, for softening rust)
  • Plastic brush (for applying rust remover)
  • Angle grinder with wire brush attachment (for heavy rust)
  • Electronic rust removal tools (optional)
  • Rust-inhibiting primer and clear coat for finishing

Step-by-Step Guide to Removing Rust from Coca-Cola Machines

Step 1: Prepare the Work Area

Rust removal can be messy and sometimes requires the use of chemicals and power tools, so setting up a safe and clean workspace is essential:

  • Protect the Area: Use plastic sheeting or drop cloths to protect your work area from debris, rust particles, and chemicals.
  • Ventilate the Area: Ensure your workspace is well-ventilated, especially if you are using chemicals or power tools that generate dust.
  • Wear Protective Gear: Always wear chemical gloves, safety glasses, and a respirator (if using sandblasting or strong chemicals) to protect yourself from rust dust, sharp debris, and chemical fumes.

Step 2: Manual Rust Removal (For Light Rust)

If the rust is light, you can start by using basic hand tools to remove it:

  1. Wire Brush or Steel Wool: Use a wire brush or steel wool to scrub away light rust. Work in small sections and use circular motions to remove the rust.
  2. Sandpaper: After the initial scrubbing, use medium-grit sandpaper (around 80-grit) to smooth the surface, and finish with fine-grit sandpaper (220-grit) for a polished look.
  3. Clean the Area: Wipe the surface with a clean cloth to remove rust particles and dust.

Step 3: Using Power Tools for Heavy Rust

For more extensive rust or rust that has penetrated the surface, you may need to use power tools:

  1. Angle Grinder or Power Sander: For severe rust, use an angle grinder with a wire brush attachment or a power sander with coarse-grit sandpaper. Work in small sections, and be careful not to grind too deeply into the metal.
  2. Heat Gun: If rust is particularly stubborn, you can use a heat gun to soften the rust, making it easier to scrape off with a wire brush or power sander.

Step 4: Sandblasting (For Extensive Rust or Large Areas)

Sandblasting is a highly effective method for removing rust from larger areas, especially when the rust is severe or widespread.

  1. Prepare for Sandblasting: Sandblasting works by using abrasive material, such as sand, to physically remove rust. If you’re using a sandblaster, you’ll need a sandblasting cabinet or outdoor setup to contain the debris.
  2. Use Proper Abrasive Material: Aluminum oxide or glass beads are ideal for sandblasting, as they can remove rust without damaging the underlying metal.
  3. Start Sandblasting: Wear a respirator to avoid inhaling the fine dust, and set the machine to a moderate pressure. Move the nozzle in smooth, even strokes across the rusty area, keeping a consistent distance from the surface.
  4. Clean the Area: Once the rust is removed, wipe the area with a damp cloth to remove any remaining debris, and allow the surface to dry completely.

Step 5: Chemical Rust Removers (For Light to Medium Rust)

Chemical rust removers are a popular option when you want to dissolve rust without using abrasive tools.

  1. Choose a Rust Remover: There are several chemical rust removers available, such as Evapo-Rust or Rust-Oleum Rust Dissolver, that effectively break down rust.
  2. Apply the Solution: Use a plastic brush to apply the rust remover directly to the affected areas. Follow the product instructions, as some rust removers may require soaking the metal for 30-60 minutes.
  3. Wipe and Rinse: After the rust has dissolved, rinse the area thoroughly with water and wipe it down with a clean cloth. Repeat if necessary.

Step 6: Chemical Rust Converters (For Remaining Rust)

Even after removing most of the rust, small patches of stubborn corrosion may remain. A rust converter can be applied to neutralize and convert the remaining rust into a stable, non-reactive substance.

  1. Apply Rust Converter: Use a rust converter like Permatex Rust Treatment or Corroseal. Apply it to any remaining rust areas using a brush or rag. Rust converters are typically a liquid that chemically transforms rust into a protective coating.
  2. Let It Dry: Allow the rust converter to dry completely, which can take several hours or overnight, depending on the product.
  3. Check for Coverage: If necessary, apply a second coat for better protection.

Step 7: Electronic Rust Removal (For Delicate or Detailed Areas)

For delicate or intricate areas of the machine, electronic rust removal (also known as electrolysis) can be an excellent option.

  1. Prepare the Electrolysis Setup: You will need a plastic container, sodium carbonate (washing soda), a DC power supply, and a sacrificial anode (usually a piece of steel).
  2. Submerge the Part: Fill the container with water and sodium carbonate, then submerge the rusty part of the machine along with the sacrificial anode. Attach the positive lead from the power supply to the anode and the negative lead to the rusty part.
  3. Start the Process: The rust will slowly dissolve as the electric current passes through the water, turning the rust into a more easily removable form. This process may take several hours.
  4. Clean the Part: After the electrolysis process, remove the part and scrub it with a wire brush to remove any loose rust or residue. Rinse and dry thoroughly.

Step 8: Final Surface Treatment

Once all the rust is removed, it’s crucial to treat the metal surface to prevent future rusting.

  1. Apply a Rust-Inhibiting Primer: After the metal has been cleaned, apply a rust-inhibiting primer. This will help prevent rust from returning and provide a good base for painting.
  2. Light Sanding: Once the primer is dry, lightly sand the surface with fine-grit sandpaper to remove any imperfections.
  3. Painting: Now, you’re ready to apply a fresh coat of paint, and any decals or logos, to complete the restoration.

Conclusion

Removing rust from your Coca-Cola machine is an essential step in restoring it to its original beauty. Whether you choose manual methods, sandblasting, chemical rust removers, or electronic rust removal, the key to a successful restoration is patience and the right tools for the job. Once the rust is completely removed and the surface treated, you can confidently move on to repainting and adding decals, knowing that the machine will look great and last for years to come.

Good luck with your restoration, and enjoy the process of bringing a piece of Coca-Cola history back to life!