Surface Finishing Services for CNC Prototypes
JIERCHEN applies 11 finishing processes to CNC-machined and vacuum-cast prototypes — from spray painting and anodizing to laser engraving and electroplating — so appearance samples match production intent before you commit to tooling.
Discuss Your Finish RequirementsWhy Finishing Matters at Prototype Stage
A raw CNC part rarely tells the full story. Color, gloss, grain direction, and metallic character all change how a prototype reads to a customer, a buyer, or an internal design review. JIERCHEN’s finishing line runs on the same NSV106A CNC platform and Formlabs Form 4 SLA equipment used for machining, so parts move from cutting to finishing without a change of vendor or a gap in dimensional control. Critical surfaces are still verified on a Keyence CMM to ±0.01mm after finishing, so plating thickness or masking never pushes a mating feature out of tolerance.
The processes below can be combined — for example hairline texture under spray paint, or laser engraving followed by anodizing — to match a specific production finish. Tell us the target look (a reference part, a Pantone number, or a competitor product) and we will recommend the combination.
Finishing is the last step before a prototype leaves our shop, whether the base part came from SLA 3D printing or rapid prototyping or from a full plastic and metal CNC prototype run. The same finishing line and CMM inspection apply no matter which upstream process produced the part.
11 Finishing Processes
1. Spray Painting
Material fit: Engineering plastics without coarse fiber content (ABS, PC, ABS+PC, PMMA, POM) and metals. Not recommended directly on PP, PE, PTFE, or nylon without a primer step.
Effect: Full color range, pearlescent finishes, gloss or matte topcoats, and leather-like textures on request.
When to choose it: When a prototype needs to match a specific brand color or show a painted production surface. Often paired with hairline texture or silk-screen printing for logos.
2. Polishing
Material fit: Non-fibrous engineering plastics and metals.
Effect: High-gloss or mirror-like surfaces achieved by reducing light diffraction across the part face.
When to choose it: Optical windows, chrome-like accents, or any surface that needs to read as a finished, reflective production part — usually followed by spray painting or electroplating.
3. Matte / Frosted
Material fit: Non-fibrous engineering plastics and metals.
Effect: A controlled, non-reflective finish available in varying degrees of coarseness, from a soft satin to a heavy frosted look.
When to choose it: Housings and grips where glare or fingerprint visibility is a concern. Commonly layered under spray paint, hairline texture, or silk-screen printing.
4. Hairline Texture
Material fit: Engineering plastics and metals.
Effect: Directional brushed lines produced by controlling abrasion depth and direction, giving a metal-like linear grain in varying fineness.
When to choose it: Brushed-metal aesthetics on aluminum enclosures, or a premium tactile grain on plastic housings. Frequently combined with spray painting, matte, or polishing.
5. Sandblasting
Material fit: Engineering plastics (primarily for deburring) and metals.
Effect: High-velocity compressed-air media removes burrs and produces a matte finish that varies with grit size.
When to choose it: As a deburring or pre-treatment step before painting or anodizing, or on its own for a uniform satin metal surface.
6. Electroplating
Material fit: Water plating — ABS and ABS+PC plastics, plus copper, zinc, iron, stainless steel, and aluminum. Vacuum plating — a broader range of engineering plastics, metals, and even wood substrates.
Effect: Gives the surface true metallic character with a range of metallic colors, including two-tone plating.
When to choose it: Faucet, hardware, and consumer-electronics prototypes that must show chrome, gold, or gunmetal plating. Often finished with hairline texture, laser engraving, matte, or polishing.
7. Texture / Etching
Material fit: Engineering plastics and metals.
Effect: Fine surface patterns — leather grain, geometric texture, or logo-depth etching — cut mechanically or by laser to a controlled, repeatable depth.
When to choose it: Grip zones that need texture for feel as well as appearance, or brand patterns that must appear etched rather than printed.
8. Silk-Screen Printing
Material fit: Most engineering plastics; fiber-rich materials such as PP, PE, POM, PTFE, nylon, and rubber require a rubber-specific ink. Metal-compatible inks are available for metal substrates.
Effect: Prints logos, text, or graphics in a wide color range directly onto the finished surface.
When to choose it: Branding, part numbers, or control-panel graphics. Typically applied over spray paint, polishing, matte, or hairline texture.
9. Laser Engraving
Material fit: Metals.
Effect: Laser depth control produces different metallic colors depending on the base material, with no risk of the manual inconsistency that comes with hand engraving.
When to choose it: Precision markings, serial numbers, or decorative patterns on metal parts, frequently paired with anodizing, electroplating, or electro-deposition coating.
10. Electro-Deposition Coating
Material fit: Engineering plastics and metals, including aluminum and zinc alloys.
Effect: A uniform coating that adds corrosion and flame resistance while offering a range of metallic-look colors.
When to choose it: Parts that must survive functional testing or outdoor exposure without losing their metallic appearance.
11. Anodizing
Material fit: Aluminum and aluminum alloys only.
Effect: Builds an aluminum-oxide layer that carries paint-like color options while adding oxidation resistance, corrosion resistance, and wear resistance.
When to choose it: Aluminum enclosures and structural parts that need production-grade durability as well as color, often combined with heat treatment.
Process × Material Fit
| Process | Plastics | Metals | Typical Combination |
|---|---|---|---|
| Spray Painting | Yes (non-fibrous) | Yes | Hairline, silk-screen printing |
| Polishing | Yes (non-fibrous) | Yes | Spray painting, electroplating |
| Matte / Frosted | Yes (non-fibrous) | Yes | Spray painting, hairline, silk-screen |
| Hairline Texture | Yes | Yes | Spray painting, matte, polishing |
| Sandblasting | Yes (deburring) | Yes | Pre-treatment for paint/anodizing |
| Electroplating | ABS, ABS+PC (water); broader range (vacuum) | Copper, zinc, iron, stainless, aluminum | Hairline, laser engraving, matte, polishing |
| Texture / Etching | Yes | Yes | Laser engraving |
| Silk-Screen Printing | Yes (rubber ink for fibrous types) | Yes (metal ink) | Spray painting, polishing, matte, hairline |
| Laser Engraving | — | Yes | Anodizing, electroplating, electro-deposition |
| Electro-Deposition | Yes | Aluminum, zinc alloys | Standalone protective finish |
| Anodizing | — | Aluminum only | Heat treatment |
Not sure which combination fits your part? See our full CNC material guide or the equipment behind these processes on our equipment page.
Why Buyers Trust JIERCHEN’s Finishing Line
ISO 9001
Cert No. 10319/0, issued by AFNOR
D-U-N-S 65-774-7101
Verified business identity
Since 1985
41 years of precision manufacturing
1,000+ Clients
Across 10+ countries
Frequently Asked Questions
Can you match an exact Pantone or RAL color for spray painting?
Yes. Send a Pantone/RAL reference or a physical sample and we will match spray-painted color and gloss level accordingly. Send your reference through contact us.
Which finishes work on ABS versus aluminum parts?
ABS accepts spray painting, polishing, matte, hairline texture, silk-screen printing, water or vacuum electroplating, and electro-deposition coating. Aluminum additionally accepts anodizing and laser engraving, which are not available on plastics. See the process × material table above for the full breakdown.
Can two finishes be combined on one part?
Yes — combinations such as hairline texture under spray paint, or laser engraving followed by anodizing, are common and are noted under “Typical Combination” for each process above.
Does finishing affect dimensional tolerance?
Coating and plating add a controlled thickness, so critical mating dimensions are re-verified on our Keyence CMM to ±0.01mm after finishing, not just after machining.
How long does finishing add to my lead time?
Finishing is scheduled alongside our standard CNC lead time of 3–7 days; complex multi-step finishes (for example plating plus laser engraving) may extend delivery. Confirm the exact schedule for your parts with our team.
Send Us Your Finish Reference
Share a drawing, a Pantone/RAL number, or a sample part and we’ll recommend the finishing process — or combination — that matches it.
Contact JIERCHENJIERCHEN Enterprise Co., Ltd. · ISO 9001 Cert No. 10319/0 · D-U-N-S 65-774-7101 · No. 5, Alley 19, Lane 49, Guoqing Rd., Banqiao Dist., New Taipei City 220, Taiwan · sales@jierchen.com.tw · +886-2-7728-5122
