OJTECH

Surface finishing

The right finish completes the part.

Anodizing, plating, passivation and mechanical finishing coordinated with machining, inspection and your final dimensional requirements.

Send Drawings for ReviewExplore Finishes
Materials
Aluminum · Steel · Stainless · Brass
Control
Masking · Thickness · Appearance · Final inspection
Metal components with a consistent brushed surface finish

01 / Finishing options

Common finishes, clearly compared.

The best process depends on material, function, environment and the surfaces that must remain dimensionally or cosmetically controlled.

01

Aluminum

Anodizing

Corrosion protection, wear resistance and controlled color.Type II and hard anodize; coating thickness must be considered on fits.
02

Aluminum · Steel · Brass

Electroless Nickel

Uniform corrosion and wear protection on complex geometry.Even coating build is useful for recesses, but critical dimensions need allowance.
03

Carbon Steel

Zinc Plating

Cost-effective corrosion protection for steel components.Available with different passivates; appearance and salt-spray targets should be stated.
04

Stainless Steel

Passivation

Removes free iron and supports the alloy’s corrosion resistance.Minimal dimensional change; specify the applicable standard when required.
05

Aluminum · Steel

Powder Coating

Durable color and environmental protection for larger surfaces.A comparatively thick finish; threads, grounding points and close fits often need masking.
06

Carbon & Tool Steel

Black Oxide

Low-build dark appearance with light corrosion protection.Often paired with oil or wax; not a substitute for heavy-duty corrosion protection.
07

Most Machinable Metals

Bead Blasting

A uniform matte texture that softens machining marks.A mechanical appearance process, not corrosion protection by itself.
08

Stainless · Aluminum · Brass

Brushing & Polishing

Directional grain or smoother reflective cosmetic surfaces.Define visible faces, grain direction and the acceptable appearance sample.

02 / Selection logic

Choose by purpose before appearance.

A finish should solve a defined requirement. Start with the primary job, then confirm material compatibility, coating build, masking and cosmetic expectations.

01Corrosion resistance

Anodizing · Passivation · Zinc · Nickel

02Wear resistance

Hard anodize · Electroless nickel

03Color & appearance

Anodizing · Powder coat · Brushing · Bead blast

04Minimal dimensional change

Passivation · Black oxide · Mechanical finish

05Electrical contact

Selective masking · Conversion coating review

03 / Before quotation

Five notes that prevent finishing surprises.

Clear requirements let machining, finishing and inspection work from the same intent. Include these details on the controlled drawing or RFQ package.

  1. 01

    Finish specification

    Name the process, applicable standard, type or class, color and thickness where relevant.

  2. 02

    Finished dimensions

    State whether critical limits apply before or after the surface treatment.

  3. 03

    Masking areas

    Identify threads, bearing bores, sealing faces, grounding points and press fits.

  4. 04

    Cosmetic surfaces

    Mark visible faces and define grain direction, gloss, texture and acceptable variation.

  5. 05

    Verification

    List any required coating-thickness, adhesion, salt-spray or appearance records.

Finished metal parts arranged for appearance and surface review
Final condition

Dimensions, coating, appearance and protected packing reviewed together.

04 / Quality control

Finishing is part of the manufacturing route.

OUJI coordinates the handoff from machining to finishing and back to final inspection, so critical features do not disappear between separate suppliers.

  1. 01
    Pre-finish review

    Confirm surface condition, critical dimensions, plugs and masking instructions.

  2. 02
    Supplier control

    Release the approved finish specification, sample expectation and lot requirements.

  3. 03
    Post-finish inspection

    Recheck applicable dimensions, coverage, appearance and requested documentation.

  4. 04
    Protected delivery

    Separate and pack finished surfaces to reduce contact marks during transport.

05 / FAQ

Surface finishing questions.

Practical answers for specification, dimensional control and project coordination.

Which finish should I choose for my part?

Start with the required function: corrosion, wear, appearance, conductivity or cleanability. Material, operating environment, critical fits and cosmetic expectations then narrow the practical options. OUJI can review these factors with your drawing before quotation.

Will surface finishing change part dimensions?

Many coatings add measurable thickness, while passivation and some mechanical finishes create little or no coating build. Threads, bores, sealing faces and precision fits should be reviewed in the finished condition and masked or machined with allowance when necessary.

Can you match a specific anodized or powder-coated color?

Color can be controlled to an agreed range, but alloy, surface texture, batch size and viewing conditions can create variation. For appearance-critical parts, provide a physical reference or recognized color standard and identify the visible surfaces.

Can finished parts be inspected before shipment?

Yes. Dimensional reinspection, coating-thickness checks, appearance review and required supplier certificates can be coordinated according to the drawing and purchase requirements.

Can OUJI quote machining and finishing together?

Yes. We plan machining allowance, masking, finishing, final inspection and packing as one manufacturing route, giving you one project contact and one consolidated quotation.