Mercedes-Benz S560 Wheel Repair Review: Diamond Cut Restoration

Asan Mercedes-Benz Wheel Repair: Diamond Cut Restoration from Deep Scratches

Welcome to Today's Car. Today, we're showcasing the complete diamond cut wheel repair process for a Mercedes-Benz S560. The owner had previously used another shop for a year before experiencing paint peeling issues, leading them to seek a recoating at Today's Car Asan branch. This situation is quite common, as the longevity of wheel repairs heavily depends on the initial quality and finishing methods.

Pre-Service Inspection: Assessing Damage on All Four Wheels

Upon arrival, all four wheels were meticulously inspected. Visible scratches of various sizes were apparent, with the clear coat compromised, exposing the underlying aluminum. Deeper scratches were concentrated in areas frequently exposed during driving.

The objective was clear: to restore the wheels as close to their original state as possible. Diamond cut wheel repair differs from standard painted finishes; it involves precisely machining the damaged areas and reapplying a finish, making precision paramount.

Step 1: Surface Refinement with Sandblasting

First, the wheels were separated from the tires. The subsequent sandblasting is a critical step. This process uses high-pressure, ultra-fine sand particles to remove all contaminants and oxidation layers from the wheel surface, directly enhancing adhesion for subsequent coatings.

Following sandblasting, a dedicated cleaning agent is used to remove any oils. This double-cleaning process is essential for maximizing the adhesion of the underlying paint layers. Skipping this can lead to future paint peeling issues.

Step 2: CNC Diamond Cutting - The Core of Precision Machining

This is the heart of the diamond cutting process. Using specialized CNC equipment for wheels, the damaged sections are precisely machined away. A crucial judgment here is determining the machining depth; going too deep can compromise the wheel's structural integrity.

For deep scratches, aluminum welding is employed to create a new surface. This technique minimizes excessive machining, thereby preserving the wheel's strength. This stage truly highlights the technician's experience; incorrect judgment leading to over-machining can cause wheel deformation.

Aluminum chips and dust generated during diamond cutting must be meticulously removed. Any remaining fine particles can mar the surface finish in the next stage. A secondary cleaning with a soft sponge is performed, followed by a final degreasing treatment.

Step 3: Powder Coating Clear – The Key to Durability

A critical choice here is the type of clear coat. For diamond cut wheels, powder clear coating is recommended over standard liquid (fluid) clear coats due to superior adhesion and durability.

Powder coating involves applying a powdered paint electrostatically, followed by high-temperature curing (around 200°C or higher). This method offers significantly higher mechanical strength than liquid coatings, making it more resistant to impacts and friction experienced by wheels. We've seen cases where vehicles using only liquid clear coats experienced peeling within 1-2 years.

Liquid coatings can struggle with adhesion on diamond cut surfaces, but powder clear coats bond much better. This superior adhesion is achieved through a chemical bond formed during the high-temperature curing process, which is the decisive factor for long-term durability.

Finishing and Completion: Wheels Restored Like New

After the powder coating was fully cured, the wheels and tires were reassembled. All pre-existing scratches were eliminated, leaving the wheels looking as if they were brand new.