For any questions about our services you can call us at: +86-188-7042-1176
High-Precision Polishing & Buffing Services
Polishing is the art of removing surface imperfections to achieve a specific level of smoothness and reflectivity. It is often the final and most critical step in manufacturing cosmetic or functional parts. Whether you require a Mirror Finish (SPI A-2) for a mold insert to release plastic parts cleanly, or Optical Clarity for a transparent acrylic prototype, the quality of the polish defines the quality of the part.
At JUCHENG, we combine automated tumbling technology with the skilled hands of master craftsmen. We remove CNC tool marks, EDM craters, and 3D printing layer lines to lower the Surface Roughness (Ra) to sub-micron levels. Our facility handles everything from soft aluminum and plastics to hardened tool steels, delivering finishes that are both functional (low friction/sanitary) and beautiful.
Polishing

JUCHENG’s Surface Finishing Spectrum

We offer a gradient of finishes tailored to your specification:
  • Manual Buffing: Skilled technicians use abrasive belts, sanding pads, and cloth wheels with polishing compounds to progressively smooth the surface from a rough machine cut to a high gloss.
  • Vapor Polishing: Specifically for Polycarbonate (PC) and Polysulfone. We use chemical vapor to melt the surface layer at a microscopic level, instantly turning a translucent machined part into a water-clear window.
  • Mold Polishing: We follow SPI (Society of the Plastics Industry) standards, polishing hardened steel molds with diamond paste to achieve A-grade mirror finishes required for lens molding.
  • Brushing / Satin: Instead of a mirror shine, we can apply a directional grit pattern (hairline) that hides fingerprints and scratches, popular in appliance design.
  • Ra Control: We can target specific roughness values, such as Ra 0.4µm for sanitary seals or Ra 0.05µm for optical reflectors.
Mirror Finish

Product Gallery Categories

Optical Clear Plastics
Optical Plastic Polishing
Mirror Polished Stainless Steel
SPI Mold PolishingSPI Mold Polishing
Mold Cavity Finishing
Brushed Satin Finish
Brushed/Satin Metal
Brass Copper Buffing
Functional Low-Friction Parts
Ra Roughness Inspection

Materials Available

Materials We Polish
Different materials require different abrasives and compounds to achieve a shine:
Material Class Polishing Method Expected Result
Stainless Steel (304/316) Mechanical Buffing Bright, chrome-like mirror finish. Highly durable.
Aluminum (6061) Buffing & Bright Dip Shiny silver finish. Must be anodized or clear-coated immediately to prevent oxidation.
Tool Steel (D2/H13) Diamond Paste Hard, defect-free mirror surface for molding.
Plastics (PMMA/Acrylic) Wet Sanding + Buffing Exceptional clarity. Used for light guides.
Plastics (PC) Vapor Polishing Restores transparency to internal features and complex geometries.
Brass Buffing Deep, golden luster. Requires lacquer to prevent tarnishing.

Comparison

Comparison: Mechanical Polishing vs. Electropolishing vs. Vapor Polishing
How to choose the right smoothing method?
Feature Mechanical Polishing (Hand/Buffing) Electropolishing (Chemical) Vapor Polishing (Chemical Gas)
Target Material All Metals & Rigid Plastics Stainless Steel Only PC, PSU, PEI (Plastics)
Finish Quality Mirror / High Gloss Bright / Clean Optical Clear
Geometry Exterior surfaces (Line of sight) Complex shapes & internals Complex internal channels
Material Removal Varies (Can affect tolerance) Minimal (Surface leveling) Minimal (Surface melting)
Main Benefit Aesthetics & smoothness Hygiene & corrosion resistance Transparency

Why Choose Us

  • Preserving Geometry: Over-polishing can round off sharp corners or ruin press-fit tolerances. Our technicians are trained to polish surfaces while maintaining critical edge definition and dimensions.
  • Consistency: For batch production, we use automated tumbling or robotic polishing arms where possible to ensure every part looks identical.
  • Measurement: We don't guess. We verify surface finish requirements using calibrated Ra Profilometers to provide data-backed quality reports.
  • Protection: Polished surfaces are delicate. We apply protective tapes or vacuum packing immediately after finishing to ensure parts arrive scratch-free.

Advantages

  •  Hygiene: A smooth surface has nowhere for bacteria or dirt to hide, making it essential for medical and food-grade parts.
  • Friction Reduction: Lower Ra values mean less friction and wear for moving parts like shafts and pistons.
  • Optical Performance: Essential for light transmission in lenses and reflectors.
  • Aesthetics: Increases the perceived value of a product by giving it a premium, jewelry-like appearance. 

Industries Served

  • Medical: Surgical instruments, implants, and sanitary fluid manifolds (Electropolished/Buffed).
  • Automotive: Interior chrome trim, reflectors, engine valve components.
  • Mold Making: Injection molds requiring SPI A-1 to A-3 finishes for clear parts.
  • Optics: Lenses, prisms, light pipes, and mirrors.
  • Consumer Goods: High-end audio equipment, jewelry, watches.
Jucheng Precision Factory
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    Factory Address :
    Shenzhen: Fourth Industrial Zone, Xisha Road, Shajing Street, Baoan District, Shenzhen.
    Dongguan: Building 5 and 4, No. 198, Chang'an Section, Guanchang Road, Chang'an Town, Dongguan.
     
    Sales Office: 
    unit 1, Enterprise City,Durham DL16 6JF, united Kindom
     
     
    +86 - 186 - 8005 - 3076
    project@juchengjm.com
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    Capabilities

    CNC Machining
     
     
    Jucheng Precision ISO 9001, ISO 14001, ISO 13485, IATF 16949

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