Sanding aluminum wheels is a key step in restoring or refinishing them, often done to remove imperfections or prepare the surface for polishing or painting.
Sanding aluminum wheels involves using a series of progressively finer sandpaper grits to smooth the surface, remove scratches, oxidation, or curb rash, and prepare the metal for subsequent steps like polishing or painting.
The Purpose of Sanding Aluminum Wheels
Aluminum wheels can suffer from various forms of damage and wear, including:
- Oxidation: A chalky, dull appearance caused by exposure to the elements.
- Curb Rash: Scratches and gouges from hitting curbs.
- Scratches and Swirl Marks: From washing, road debris, or previous refinishing attempts.
- Clear Coat Peeling or Damage: On coated wheels, the clear layer can fail.
Sanding helps to level the surface, remove these imperfections, and create a uniform texture that is ideal for achieving a high-quality finish, whether you're aiming for a mirror-like shine through polishing or a smooth base for paint or powder coating.
Sanding Process and Grit Progression
The process typically involves starting with a coarser grit sandpaper to tackle the worst imperfections and gradually moving to finer grits to smooth out the sanding marks left by the previous grit. The choice of starting grit depends on the severity of the damage.
Here's a general outline:
- Clean the Wheels: Thoroughly wash the wheels to remove all dirt, brake dust, and grease. Any contaminants left on the surface can scratch the aluminum during sanding.
- Assess Damage: Determine the extent of the imperfections. This helps you choose your starting grit.
- Start with Coarser Grit: For significant damage like deep scratches or curb rash, you might start with grits around 180 or 220. Use the sandpaper with a sanding block or a hook pad on a sander. Sand the damaged areas until the imperfections are significantly reduced or removed.
- Progress to Finer Grits: Once the initial imperfections are addressed, move to the next finer grit. As shown in some methods, after using a grit like 220, it's time for the 400 grit sandpaper. You will just place it on our hook a pad then sand everywhere we sand with a 220 grit sandpaper. This step removes the deeper scratches left by the 220 grit.
- Continue Refining: Keep moving to progressively finer grits (e.g., 600, 800, 1000, 1500, 2000, or even higher). The goal is to remove the sanding marks from the previous grit. Sanding until you reach grits like 1000 or 1500 is often sufficient if you plan to paint the wheels. If you aim for a polished mirror finish, you'll need to sand to much finer grits (2000 and beyond) before moving on to polishing compounds.
- Clean Between Grits: It's crucial to clean the wheel surface between grit changes to remove sanding dust and ensure you're seeing the true surface and the marks left by the current grit. This also prevents coarser particles from contaminating your finer sandpaper.
- Final Inspection: After completing the sanding steps, inspect the wheel surface under good light to ensure all previous grit marks are gone and the surface has a uniform appearance according to your final finish goal.
Common Sandpaper Grit Progression Example
| Grit Level | Purpose | Typical Use Case |
|---|---|---|
| 180-220 | Removing heavy scratches, curb rash, thick oxidation | Initial removal of significant damage |
| 400 | Refining marks from coarser grits | Following 220 grit, preparing for next steps |
| 600 | Further smoothing, preparing for higher grits | Reducing 400 grit marks |
| 800-1000 | Preparing for paint or fine polishing | Creating a smooth base for coatings or light polish |
| 1500+ | Preparing for mirror polishing | Removing fine scratches before buffing and polishing |
Note: The specific grits used and the steps may vary slightly depending on the condition of the wheel and the desired outcome.
Tools and Materials
- Various grits of wet/dry sandpaper (as mentioned, starting with coarser grits like 220 and moving up to 400 and beyond is typical).
- Sanding blocks or pads (including hook pads for sanders).
- Orbital sander (optional, speeds up the process on flatter areas).
- Cleaning supplies (wheel cleaner, brushes, microfiber towels).
- Water source (for wet sanding).
- Safety gear (gloves, dust mask or respirator, eye protection).
Sanding is a labor-intensive process, especially if done by hand, but it's essential for achieving a smooth, restored finish on aluminum wheels.
