What is a hairline finish?
A hairline finish consists of fine, continuous parallel lines running in a single direction across the stainless steel surface. The name comes from the hair-thin scratches created by abrasive belts — visible to the eye but nearly flat to the touch.
In industry standards, hairline is classified as No.4 finish (#4) or HL finish per ASTM A480 and JIS G4305. It is the most widely used stainless steel finish in architecture, high-end interiors, and commercial equipment — from elevator doors and building facades to industrial kitchen counters.
Why hairline over mirror (#8)?
- Hides fingerprints — the brushed texture diffuses light, making smudges nearly invisible
- Conceals minor scratches — everyday wear blends into the existing grain pattern
- Easy maintenance — wipe with a damp cloth, no special chemicals needed
- Lower cost than mirror — fewer polishing steps, simpler process
Comparing stainless steel surface finishes
| Designation | Common name | Description | Ra (um) | Fingerprints | Cost | Primary use |
|---|---|---|---|---|---|---|
| 2B | Mill finish | Factory default, slightly dull | 0.1–0.5 | Visible | Lowest | Hidden structures, internal frames |
| #4 / HL | Hairline / Brushed | Fine parallel lines | 0.2–1.5 | Nearly invisible | Medium | Elevators, facades, interiors |
| #6 | Satin | Softer than #4, slight sheen | 0.1–0.5 | Low | Medium–high | Medical, food equipment |
| BA | Bright Annealed | Soft mirror (annealed) | 0.05–0.1 | Visible | High | Reflective panels, decorative |
| #8 | Mirror | Perfect mirror finish | ≤ 0.05 | Very visible | Highest | High-end decorative, mirrors |
Key takeaway: Hairline (#4/HL) offers the best balance of aesthetics, surface durability, and cost. That is why roughly 80% of architectural stainless steel projects specify hairline.
The hairline process — 4 steps
Step 1: Surface preparation
The stainless steel sheet is degreased and cleaned to remove oil, dust, oxide layers, and weld marks (if applicable). For welded assemblies, weld beads are ground flush with flap discs or sanding belts before entering the hairline process. The surface must be completely clean — any remaining particle will cause an off-direction scratch.
Step 2: Abrasive belt grinding
The sheet passes through a brushing machine with abrasive belts running continuously in one direction:
- Standard hairline: 80–120 grit belts — produces pronounced lines, common for architectural exteriors, elevators, column cladding
- Fine hairline: 150–240 grit belts — finer lines, softer appearance, used for high-end interiors, signage, appliances
Belt speed, contact pressure, and number of passes determine the depth and uniformity of the hairline pattern.
Step 3: Direction control
The entire sheet must have lines running in a single, consistent direction with even pressure throughout. Uneven pressure creates light/dark zones visible under ambient lighting — the most common defect in low-quality hairline work.
For multi-panel assemblies (column cladding, elevator cabins), grain direction must be uniform across all panels to prevent a patchwork appearance after installation.
Step 4: Protective film application
Immediately after finishing, the surface is covered with PE protective film. This film remains in place until final installation at the job site. Any scratch on a finished hairline surface cannot be spot-repaired — the entire panel must be re-finished.
Materials we hairline finish
| Grade | Characteristics | Thickness | Notes |
|---|---|---|---|
| 304 (SUS304) | Most common, good corrosion resistance | 0.5–6mm | 90% of hairline orders |
| 316 (SUS316) | Superior chemical/marine resistance | 0.5–6mm | Pools, coastal, chemical plants |
| 430 (SUS430) | Magnetic, lower cost than 304 | 0.5–4mm | Appliances, budget interior cladding |
We apply hairline AFTER fabrication — this is a critical distinction. Instead of buying pre-finished hairline sheets and then cutting them (which damages the surface at cut edges and bend lines), our process is:
Laser cut → CNC bend → Weld → Grind welds → Hairline finish → Protective film
The result: a hairline surface that is continuous across weld seams, with no grain interruption or direction shifts at bend lines.
Applications for hairline stainless steel
Architecture and construction
- Elevator doors and panels — the most common application, requiring uniform hairline across matched panels
- Building facades — exterior hairline stainless cladding, weather resistant
- Staircase handrails — round or square tube, hairline finished
- Column cladding — curved sheets wrapping concrete columns, vertical grain
- Door frames and corner trims — long profile pieces, hairline along the length
Interiors and decorative
- Countertops and bar tops — commercial kitchens, reception desks, restaurant counters
- Signage and nameplates — raised stainless letters, company logos
- Table legs and chair frames — office and restaurant furniture
- Display shelving — showrooms, retail stores
Industrial equipment
- Electrical enclosures — hairline exterior panels, fingerprint resistant during operation
- Cable trays and machine housings — clean appearance for clean rooms, food plants
- Kick plates — scratch-resistant panels at door bases
One-stop hairline fabrication — our advantage
Many laser cutting shops deliver raw parts, leaving the customer to find a separate polishing vendor. This split workflow causes:
- Inconsistent grain direction between parts (different shops use different machines)
- Transport scratches — unprotected parts get damaged in transit
- Visible weld lines — polishing shops often do not grind welds flush enough before hairline
- Extended lead time — 3–5 extra days waiting for the external finishing step
At Tuan Thinh, the entire workflow from laser cutting to hairline finishing happens under one roof:
- CNC laser cutting from DXF/DWG files
- CNC bending to specification
- TIG/MIG welding (if required)
- Weld bead grinding flush
- Hairline finishing
- Protective film, packing, and delivery
One point of contact, one delivery, and a hairline surface that is uniform across the entire product.
Grain direction — a small detail that matters
The direction of hairline grain directly affects the aesthetics of the finished installation:
| Application | Recommended grain | Reason |
|---|---|---|
| Elevator panels | Vertical | Creates a sense of height, hides fingerprints at hand level |
| Kick plates | Horizontal | Blends with shoe scuff marks |
| Column cladding | Vertical | Makes columns appear taller and more slender |
| Countertops | Horizontal (along length) | Natural appearance, conceals usage scratches |
| Exterior facades | Vertical | Architectural standard, rainwater follows the grain |
| Signage | Per design | Must be specified in drawings |
Important rule: When ordering multiple panels that will be assembled together (column wraps, elevator cabins), specify grain direction on your drawings and number the panels in installation order. We finish all panels in a single batch to guarantee consistency.
Reference pricing — hairline finishing on stainless steel
Hairline finishing is priced per surface area (m2), excluding laser cutting, bending, or raw material costs:
| Grade | Thickness | Reference price (VND/m2) |
|---|---|---|
| 304 | 0.5–1.0mm | 80,000 – 120,000 |
| 304 | 1.2–2.0mm | 100,000 – 150,000 |
| 304 | 2.5–4.0mm | 130,000 – 180,000 |
| 304 | 5.0–6.0mm | 160,000 – 220,000 |
| 316 | 0.5–1.0mm | 90,000 – 130,000 |
| 316 | 1.2–2.0mm | 110,000 – 160,000 |
| 316 | 2.5–4.0mm | 140,000 – 200,000 |
| 316 | 5.0–6.0mm | 180,000 – 250,000 |
| 430 | 0.5–1.0mm | 60,000 – 90,000 |
| 430 | 1.2–2.0mm | 80,000 – 120,000 |
| 430 | 2.5–4.0mm | 100,000 – 150,000 |
Notes:
- Minimum order: 0.5 m2 (minimum charge equivalent to 0.5 m2)
- 10% discount for orders of 20 m2 and above
- 15% discount for orders of 50 m2 and above
- Weld bead grinding before hairline: add 50,000–100,000 VND per meter of weld
- Prices above are for standard hairline (80–120 grit). Fine hairline (150–240 grit) adds 20%
Pricing depends on geometry, quantity, and specific requirements. Send your drawings for an exact quote.
Order hairline finishing from Tuan Thinh
We provide hairline finishing on stainless steel 304, 316, and 430 from 0.5mm to 6mm — as a complete fabrication package from laser cutting to hairline, or as a standalone finishing service for your existing parts.
- Send DXF/DWG files with grain direction noted via Zalo or email
- Receive a detailed quote within hours
- Free delivery within Binh Duong province
View our full fabrication capabilities on the services page or request a quote now.