Secondary Processes · Surface Finishing

Surface Finishing Support for CNC Machined and Sheet Metal Parts

OUJI helps overseas buyers coordinate machining, anodizing, plating,
passivation, bead blasting, polishing, powder coating, masking review,
coating thickness checks, and post-finish inspection in one practical
project workflow.

Machining + finishing review
Masking and critical dimension check
Inspection and packaging support

surface finishing services for custom CNC machined and sheet metal parts
Before production
We review material, coating thickness, masking areas, threads, cosmetic surfaces, and critical post-finish dimensions.

12h
Initial quote response for clear drawings
7d
Fast delivery option for simple CNC parts
30d
Typical planning target for multi-process projects
QC
Visual, dimensional, coating and packaging review

Why It Matters

Surface Finishing Is Not Only About Appearance

A surface finish can affect corrosion resistance, conductivity, wear
resistance, color appearance, thread fit, assembly clearance, and final
product quality. For overseas buyers, the risk is often not the finishing
process itself — the risk is poor review before the parts are sent out
for finishing.

OUJI reviews the drawing notes, base material, critical dimensions,
cosmetic surfaces, masking areas, and inspection requirements before
arranging finishing, so the machining and finishing route can be planned
together.

Coating thickness may affect fit and tolerance.
Threads, holes, and sealing faces may need masking.
Color and texture expectations should be confirmed early.
Finished parts need better packaging protection.

finished machined parts with drawing and inspection review

Finishing Options

Common Surface Finishing Options We Coordinate

We support practical finishing options for prototype, small-batch, and
custom production parts. Final availability depends on material, part
geometry, cosmetic requirements, tolerance needs, and drawing notes.

OUJI anodized aluminum sample parts with laser marked logo
Aluminum Finish

Anodizing

Common for aluminum housings, brackets, panels, covers, and CNC parts
requiring corrosion resistance, color, or improved surface hardness.

  • Clear, black, selected custom colors
  • Type II / selected hard anodizing review
  • Color, masking and thread-fit review
OUJI electroplated nickel silver gold sample parts
Conductive Finish

Electroplating

Used for steel, brass, copper, aluminum, RF, electronics, connector,
and functional components requiring protection or conductivity.

  • Nickel, zinc, copper, tin, silver, gold
  • Conductive and anti-corrosion applications
  • Thickness and contact surface review
OUJI passivated stainless steel machined parts
Stainless Steel

Passivation

Suitable for stainless steel parts requiring improved corrosion
resistance while maintaining a clean metal surface.

  • Stainless steel machined parts
  • Medical, industrial and clean hardware
  • Surface cleanliness and stain review
OUJI bead blasted matte aluminum machined parts
Matte Texture

Bead Blasting

Creates a matte, uniform texture and can be combined with anodizing
or other finishes for cosmetic aluminum parts.

  • Matte cosmetic appearance
  • Aluminum housings and covers
  • Texture direction and surface uniformity
OUJI polished stainless steel aluminum and brass parts
Smooth Surface

Polishing

Used for parts requiring smoother surfaces, decorative appearance,
reduced machining marks, or functional contact surfaces.

  • Stainless steel, aluminum, brass
  • Cosmetic and functional surfaces
  • Flatness and edge condition review
OUJI powder coated sheet metal enclosure and bracket parts
Color Coating

Powder Coating

Common for sheet metal enclosures, brackets, panels, and structural
parts requiring durable color coating.

  • Sheet metal and fabricated parts
  • Durable color finish
  • Coating build-up and masking review
OUJI black oxide steel machined components
Black Finish

Black Oxide

Suitable for selected steel components requiring black appearance,
light corrosion resistance, or reduced reflection.

  • Steel components
  • Black appearance
  • Oil protection and storage review
OUJI conversion coated aluminum machined parts
Conductive Base

Conversion Coating

Used for aluminum parts requiring corrosion resistance, electrical
conductivity, or a suitable base for later coating.

  • Aluminum parts
  • Conductive surface applications
  • Drawing specification review

surface finishing masking and critical dimension review for machined parts
Before Finishing

We Review the Details That Often Cause Finishing Problems

Many finishing issues happen because the part was machined correctly,
but the coating thickness, masking zones, cosmetic faces, or post-finish
dimensions were not reviewed early enough.

Base Material
Aluminum, stainless steel, steel, brass, copper, and selected plastics.
Finish Type
Anodizing, plating, passivation, coating, polishing, blasting, or black oxide.
Critical Dimensions
Holes, threads, slots, bearing areas, sealing faces, and assembly features.
Masking Areas
Grounding surfaces, datum faces, non-coated zones, threads, and contact areas.
Cosmetic Surfaces
Visible faces, color, texture, scratches, stains, gloss, and direction marks.
Inspection Needs
Coating thickness, visual check, dimensional check, and report support.

Inspection Support

Post-Finish Inspection and Documentation Support

For finished parts, OUJI can support visual inspection, coating coverage
review, selected coating thickness checks, critical dimension checks,
packaging protection, and documentation based on customer requirements.

Coating Thickness Check

Selected plated, anodized, or coated parts can be checked for coating
thickness when required by the drawing or customer specification.

Critical Dimension Review

Threads, holes, slots, sealing faces, bearing areas, and fit surfaces
can be reviewed after finishing to reduce assembly risk.

Cosmetic Surface Review

Visible surfaces, color consistency, scratches, stains, dents, and
texture direction can be checked before shipment.

Protective Packaging

Finished parts can be packed with surface protection to reduce
scratches, rubbing marks, and coating damage during transport.

Typical Projects

Surface Finishing for Functional and Cosmetic Custom Parts

We focus on finishing support for drawing-based custom parts where
appearance, corrosion resistance, conductivity, fit, and packaging all
matter to the final project result.

Aluminum Housings and Covers

Anodized, bead blasted, polished, or conversion-coated aluminum parts
for electronics, devices, automation equipment, and enclosures.

RF and Conductive Components

Plating review for copper, brass, aluminum, and selected conductive
components requiring controlled contact areas and coating thickness.

Stainless Steel Parts

Passivation, polishing, brushing, or cleaning support for corrosion
resistance, appearance, and functional surfaces.

Sheet Metal Enclosures

Powder coating, plating, brushing, and finishing support for brackets,
panels, covers, frames, and enclosure components.

Project Workflow

How We Coordinate Machining and Surface Finishing

We review the finishing requirement together with machining, not as an
afterthought. This helps reduce rework, cosmetic rejection, fit issues,
and shipment delays.

01

Drawing Review

We check material, finish notes, coating thickness, tolerances,
cosmetic requirements, masking areas, and inspection needs.

02

Machining Route

We review whether the part should be machined before or after certain
finishing steps and whether allowance is needed.

03

Finishing Coordination

We coordinate anodizing, plating, passivation, blasting, polishing,
coating, or other required secondary processes.

04

Final Check and Packing

We review visible surfaces, coating coverage, selected dimensions,
documentation needs, and protective packaging before shipment.

FAQ

Surface Finishing Questions from Overseas Buyers

Can OUJI provide machining and surface finishing together?

Yes. We can coordinate CNC machining, sheet metal fabrication, and
secondary processes such as anodizing, plating, passivation, bead
blasting, polishing, powder coating, and selected inspection support.

Can you check coating thickness?

For selected plated, anodized, or coated parts, coating thickness
checks can be arranged based on drawing notes, customer requirements,
and project feasibility.

Do finishing processes affect tolerances?

Yes. Anodizing, plating, coating, and other finishes may add material
thickness or affect surface conditions. We review threads, holes,
fits, datum surfaces, and critical dimensions before quoting.

Can you mask threads or contact surfaces?

Yes. Threads, contact surfaces, grounding areas, sealing faces, datum
surfaces, and other non-coated zones can be reviewed for masking when
the drawing or application requires it.

Can you support cosmetic parts?

Yes. For cosmetic parts, please provide color, texture, visible surface,
scratch tolerance, packaging, and acceptance requirements. We will
review these details before production.

What should I send for a surface finishing quote?

Please send 2D drawings, 3D files, material, quantity, finish type,
color or coating requirement, masking notes, critical dimensions, and
target lead time.

Ready to Review Your Project?

Send Your Drawings for Machining and Finishing Review

Send your drawings, material, quantity, finish type, color or coating
requirement, masking areas, and critical post-finish dimensions. OUJI
will review the machining and finishing route together before quoting.

  • STEP / IGES / PDF drawings
  • Material and finish requirement
  • Color, texture, or coating thickness notes
  • Masking areas and critical dimensions
  • Quantity and target lead time

Send Drawings for Quote