No.4 Surface Finish

No.4 Finish Stainless Steel – The Most Popular Brushed Finish

No.4 finish, also known as brushed or satin finish, is the most popular decorative stainless steel finish worldwide. Its fine linear grain pattern offers a modern, professional look while effectively hiding fingerprints and minor scratches, commonly used with 300 series stainless steel.

What is No.4 Finish?

No.4 finish is created by polishing stainless steel with 150–180 grit abrasive belts, resulting in a unidirectional, fine satin texture.

Detailed Production Process

1. Start from 2B or BA base material.
2. Initial grinding with coarse abrasives (60–120 grit).
3. Progressive polishing with finer grits (up to 180 grit).
4. Final pass to create uniform linear pattern.
5. Cleaning and passivation.

Key Characteristics

• Directional linear brush pattern.
• Surface roughness (Ra): approximately 0.3–0.8 µm.
• Medium reflectivity (satin sheen).
• Excellent scratch and fingerprint resistance.

Advantages

1. Hides imperfections – effectively conceals fingerprints and scratches.
2. Modern appearance – widely accepted in contemporary design.
3. Cost-effective decoration – more affordable than mirror or HL finishes.
4. Good cleanability – smooth enough for easy cleaning.
5. Widely available – standard stock item in most sizes.

Limitations

• Directional pattern requires consistent orientation during installation.
• Not as hygienic as mirror or BA finishes.
• Can show deeper scratches if not maintained.

Typical Applications

• Kitchen countertops and splashbacks.
• Commercial kitchen equipment.
• Elevator interiors.
• Restaurant and bar fittings.
• Architectural cladding and trim using stainless steel sheets.
• Furniture and fixtures.
• Medical carts and cabinets.

Maintenance and Cleaning

• Clean in the direction of the grain.
• Use mild detergent and soft cloth.
• Stainless steel polish restores appearance.

No.4 finish remains the industry standard for decorative stainless steel applications due to its perfect balance of aesthetics, durability, and cost. Widely used with 400 series stainless steel for various applications.