How Premium Handmade Stainless Steel Sinks Are Manufactured: A Complete Step-by-Step Production Guide

Publish Time: 2025-11-21     Origin: Site

Handmade stainless steel sinks differ significantly from mass-produced, deep-drawn sinks created through hydraulic stamping. Instead of using thin metal sheets stretched into shape, a handmade sink is crafted by folding and welding a single thick stainless steel plate, typically 1.2 mm or 1.5 mm thick. This engineering method produces a more robust, durable, and structurally stable sink, with sharper corners, higher precision, and superior longevity—features highly valued in both commercial kitchens and high-end residential installations.


To help professional buyers, contractors, architects, and importers understand how quality sinks are built, the following guide outlines every stage of the stainless steel handmade sink manufacturing process, including the advanced PVD Nano finishing technology used for premium surface performance.

1. Raw Material Selection (High-Grade Stainless Steel Sheets)

Manufacturing begins with selecting certified stainless steel sheets such as SUS304 or SUS316, recognized for their corrosion resistance and hygienic performance. Sheets are sourced in precise gauges—most commonly 16 gauge (1.5 mm) or 18 gauge (1.2 mm).

Each incoming sheet undergoes strict quality checks for:

  • Mechanical stability and tensile strength

  • Micro-surface flatness

  • Chemical composition, especially chromium–nickel ratios

  • Absence of oxidation, pitting, or surface defects

Only sheets that fully comply with quality standards move forward to the precision cutting stage.

2. Laser Cutting (High-Accuracy Material Shaping)

Using fiber-optic laser systems, the metal sheets are cut according to CAD-based sink designs. This stage ensures:

  • Micron-level dimensional accuracy

  • Clean, burr-free cutting edges

  • Precise alignment for downstream folding and welding

  • High repeatability for bulk OEM/ODM orders

Laser cutting establishes the foundation for a consistent and structurally precise sink body.

3. Press Waste Hole (Drain Hole Punching)

A hydraulic punch press creates the drain opening and any additional accessory holes. The precision die ensures:

  • Perfect circularity

  • Accurate positioning

  • Compatibility with universal drainage assemblies

  • Reduced stress concentration around the punched area

Correct punching is essential for proper drainage and long-term structural reliability.

4. Folding (Sink Body Forming)

Press brakes bend the cut sheet into the sink’s main body, shaping the sides and bottom. Folding defines:

  • The internal corner radius

  • The sink’s geometric accuracy

  • Rigidity and structural stability

High-precision folding minimizes deformation and reduces stress during welding.

5. Manual Welding (Expert TIG Joint Crafting)

Highly trained welders join the folded components using TIG welding (Tungsten Inert Gas welding). Manual welding is used for areas requiring exceptional control, ensuring:

  • Smooth, clean seams

  • Maximum strength at corner joints

  • Superior durability compared to deep-drawn sinks

This step is a hallmark of handmade craftsmanship and directly impacts overall product life.

6. Automatic Welding (Reinforced Structural Bonding)

Automated welding equipment reinforces specific seams, ensuring:

  • Uniform weld penetration

  • Consistent structural performance

  • Reduced human error

  • Repeatable quality across large production batches

Combining manual and automatic welding achieves the ideal balance of artisanal precision and industrial consistency.

7. Surface Polishing (Planar & Corner Refinement)

After welding, polishing machines and skilled technicians refine the sink surface. This stage includes:

  • Surface leveling

  • Corner and seam refinement

  • Removal of welding marks or scratches

  • Achieving a uniform satin or brushed grain finish

Proper polishing creates a flawless surface and prepares the sink for premium PVD finishing.


PVD Nano Surface Finishing (Advanced Protective Coating)

(Performed between Steps 7 and 8)

PVD Nano coating enhances both durability and appearance, making the sink resistant to scratches, corrosion, and fingerprints.


A. Sanding (Abrasive Surface Conditioning)

Uniform sanding increases surface adhesion for the upcoming PVD deposition.

B. Cleaning (Ultrasonic & Chemical Treatment)

The sink undergoes deep cleaning to remove oils, dust, and residues, ensuring perfect coating adhesion.

C. PVD Titanium Coating (Physical Vapor Deposition)

Inside a vacuum chamber, titanium is vaporized and deposited onto the sink surface at 280°C.
This produces high-end finishes such as:

  • Brushed Gold

  • Gunmetal Black

  • Rose Gold

  • Bronze

  • Space Gray

PVD coating offers strong bonding and long-lasting color stability.

D. Nano Spray Coating (Protective Layer Application)

A secondary nano-coating is applied at 210°C to enhance:

  • Anti-fingerprint performance

  • Scratch resistance

  • Anti-corrosion properties

  • Overall durability

E. Oven Baking (Thermal Curing)

The sink is baked in a kiln to permanently seal and harden the nano-layer.


Performance Comparison Table

Property Standard Stainless Steel PVD Nano Stainless Steel
Surface Hardness 4.5H 8H (passes 8H pencil test)
Color Retention Moderate Permanent bonding
Scratch Resistance Basic High resistance
Anti-Fingerprint Minimal Enhanced protective layer
Expected Finish Lifespan 1–2 years 3+ years

The PVD Nano system is widely recognized as the superior finishing method for luxury and commercial sink applications.


8. EVA Anti-Noise Pad Application (Acoustic Performance Enhancement)

An EVA (ethylene-vinyl acetate) dampening pad is adhered to the underside of the sink to reduce:

  • Metallic noise

  • Water impact resonance

  • Vibration from garbage disposals

High-quality EVA pads also resist moisture absorption and maintain long-term adhesion.

9. Spray Water Absorb Layer (Condensation Protection)

A water-resistant undercoating is sprayed on the exterior to:

  • Reduce condensation buildup

  • Prevent corrosion

  • Improve thermal stability

This layer is particularly important for deep or double-bowl sinks.


10. Cleaning (Surface Treatment and Final Finish)

Technicians remove fingerprint marks, dust, and other contaminants to ensure the sink is visually perfect and ready for final inspection.


11. Inspection (Strict Quality Assurance Protocols)

The QA process includes:

  • Dimensional measurement

  • Weld strength checks

  • Surface finish inspection

  • PVD adhesion testing

  • Flatness checking

  • Water-leak simulation testing

Only sinks meeting 100% of quality standards proceed to packing.

12. Packaging (Export-Ready Protection)

To ensure safe global delivery, sinks are packaged with:

  • PE foam or protective film

  • Reinforced corner protectors

  • Heavy-duty export cartons

  • Palletized loading for container shipping

Proper packaging eliminates transit damage and ensures customer satisfaction.

Why This Process Matters for B2B Buyers

Understanding the production workflow allows buyers to evaluate:

  • Long-term product durability

  • Welding and structural integrity

  • Surface stability (especially PVD colors)

  • Manufacturing capacity and consistency

  • Certification compliance (UPC, cUPC, CE, NSF where applicable)

Factories with advanced machinery—laser cutters, robotic welders, TIG stations, polishing lines, and vacuum PVD equipment—produce higher-precision, higher-value sinks.

Factory Capability (Soft Branding)

At Aquacubic, we manufacture stainless steel handmade sinks using all the processes described above. Our PVD Nano sinks pass:

  • 8H hardness testing

  • Salt-spray and corrosion resistance testing

  • Color stability testing

We support large-scale OEM/ODM orders and comply with North American and European market standards.


FAQs

1. What material thickness is recommended for commercial handmade sinks?

Most professional buyers choose 16 gauge (1.5 mm) for maximum durability, impact resistance, and noise reduction performance.

2. Are handmade sinks better than deep-drawn sinks?

Yes. Handmade sinks are crafted from thick steel plates and welded for structural stability, while deep-drawn sinks use thinner metal and may deform over time.

3. How long does PVD Nano coating last?

With proper care, coatings maintain their color and hardness for 3 years or more, significantly outperforming standard surface treatments.

4. Can handmade sinks be customized for OEM/ODM orders?

Absolutely. Dimensions, bowl configuration, radii, drain location, and PVD colors can all be customized for large-volume orders.

5. Are these sinks compliant with North American standards?

Yes. Premium manufacturers like offer models suitable for cUPC, CE, and NSF compliant markets.



CONTACT US

  928, 128 Ji Nian Road, Baoshan District, 
      Shanghai, China.
  0086-21-61172575
  0086-18930489806
   info@aquacubic.com.cn
Copyright © 2021 AQUACUBIC All Rights Reserved  sitemap