Surface Finishing for CNC Machined & Sheet Metal Parts
FIWOK coordinates drawing-based surface finishing for CNC machined and sheet metal parts, including anodizing, plating, powder coating, passivation, and mechanical surface preparation. We review finish callouts, masking, critical dimensions, documentation, and packaging requirements before production release.
Finish Planning Before Production
Surface finishing affects appearance, corrosion resistance, wear performance, electrical properties, coating thickness, and final dimensions. Key requirements are reviewed against your drawing before production release.
Material & Finish Compatibility
Finish selection is reviewed against the base material, intended environment, functional requirements, and specified standards.
Masking & Critical Features
Threads, sealing faces, grounding locations, bearing fits, and critical dimensions can be identified for masking or dimensional review.
Documentation Scope
Certificates of Conformance, thickness records, inspection reports, and agreed documentation are confirmed during quotation.
Surface Finish Samples Gallery
Review representative finish samples for machined and fabricated parts. Actual appearance can vary with base material, part geometry, surface preparation, finish specification, and lighting conditions.
As Machined
Visible tool marks retained for functional, internal, prototype, or cost-sensitive components.
Anodizing
Type II or hardcoat anodizing options for suitable aluminum parts requiring color, corrosion protection, or wear resistance.
Bead Blasting
A uniform matte surface preparation often used before anodizing or for glare-reduced cosmetic surfaces.
Plating
Zinc, electroless nickel, and other specified plating routes for suitable corrosion, wear, or functional requirements.
Black Oxide
A conversion finish for suitable steel parts where low buildup and oil retention are required.
Polishing & Brushing
Mechanical polishing, brushing, or line graining for selected cosmetic or functional surface requirements.
How to Choose a Surface Finish
The right finish depends on the base material, operating environment, cosmetic expectations, dimensional allowances, electrical requirements, and budget. The final process route should be confirmed during drawing and quotation review.
| Primary Requirement | Finish Options to Discuss | Review Focus |
|---|---|---|
| Aluminum color, appearance & corrosion resistance | Type II anodizing or powder coating | Color, gloss, masking, cosmetic surfaces |
| Aluminum wear resistance | Hardcoat anodizing | Dimensional buildup, sealing, mating surfaces |
| Steel corrosion protection | Zinc plating, powder coating, wet painting, or black oxide | Environment, thickness, threads, packaging |
| Uniform matte appearance | Bead blasting, often before anodizing | Base material, surface texture, cosmetic acceptance |
| Uniform nickel coverage | Electroless nickel or specified plating | Thickness, hardness, functional surfaces |
| Internal or prototype parts | As machined or mechanical deburring | Burr requirements, visible surfaces, handling safety |
Materials Suitable for Surface Finishing
The appropriate chemical or mechanical finish depends on the base alloy or polymer, intended function, finish specification, and the required inspection scope.
| Base Material | Commonly Reviewed Finish Options | Important Review Points |
|---|---|---|
| Aluminum | Anodizing, hardcoat anodizing, conversion coating, bead blasting, powder coating | Alloy grade, color, thickness buildup, masking, cosmetic surfaces |
| Stainless Steel | Passivation, brushing, bead blasting, electropolishing where specified | Material grade, corrosion environment, roughness, documentation |
| Carbon Steel | Zinc plating, powder coating, wet painting, black oxide | Exposure environment, thread protection, packaging |
| Brass & Copper | Polishing, plating, passivation where suitable | Tarnish resistance, conductivity, cosmetic finish |
| Titanium | Blasting, polishing, anodizing where specified | Grade, application, cosmetic requirements |
| Engineering Plastics | Deburring, sanding, polishing, laser marking where suitable | Polymer type, heat sensitivity, chemical compatibility |
Mechanical Preparation & Assembly
Selected mechanical preparation and assembly operations can be completed before or after finishing, depending on the drawing and selected process route.
Deburring & Surface Prep
Mechanical deburring, sanding, line graining, and bead blasting prepare surfaces before final processing.
Hardware Insertion
Specified PEM nuts, studs, threaded standoffs, and other hardware can be inserted per part drawings.
Marking & Identification
Laser marking, silk screening, part numbers, batch marks, and logo identification where required.
Protective Masking
Plugs, tapes, and custom masking protect threads, sealing faces, and grounding points.
Finishing Verification & Documentation
Each order follows an agreed review and inspection approach based on the finish type, part risk, critical features, and documentation scope.
Pre-Finishing Review
Critical dimensions, threads, surface condition, cleaning needs, and masking zones are reviewed.
Thickness Review
Coating or plating thickness is checked where specified using the agreed inspection method.
Cosmetic & Adhesion
Visual acceptance, color expectations, and agreed adhesion requirements are confirmed.
Documentation Package
Available records may include CoC, thickness records, inspection reports, and agreed batch documents.
Surface Finishing FAQ
Review common drawing, color, masking, documentation, packaging, and pre-production sample questions.
How do you control coating thickness on tight-tolerance features?
We review coating thickness, dimensional allowances, threads, sealing faces, and functional features before processing. Masking methods can be specified where required.
Can you match custom colors for powder coating and painting?
Yes, where a recognized RAL, Pantone, or approved sample is provided. Color, gloss, texture, and cosmetic criteria should be confirmed during quotation.
What documentation do you provide for chemical finishes?
Depending on the agreed scope, records may include subcontractor CoC, thickness records, finish batch information, and inspection records for critical features.
Are finishing operations handled entirely in-house?
FIWOK handles selected mechanical preparation and hardware insertion in-house. Chemical and coating processes are coordinated through qualified specialist partners.
How do you pack finished parts to prevent transit scratches?
Packaging is selected according to part geometry, finish sensitivity, quantity, and shipping method. Protective separators, trays, wrapping, foam, or custom packing can be specified.
Do you support pre-production finishing samples?
Yes. Where required, prototype parts, finish samples, or test coupons can be coordinated for color, thickness, appearance, or agreed adhesion testing before volume release.
Related Manufacturing Services
Surface finishing is planned alongside part geometry, material selection, critical dimensions, hardware requirements, and final packaging. Explore the manufacturing services that support your finished part program.
Ready to Review Your Finishing Requirements?
Send your drawing package and finish specification for a practical manufacturing and finishing review. We will confirm the applicable process route, masking needs, documentation scope, and packaging requirements before quotation.
Send RFQ to: sales@fiwokmetalworks.com
Recommended RFQ Checklist:
- Technical Drawings: 2D drawings and 3D files showing critical dimensions, threads, masking zones, cosmetic surfaces, and tolerance requirements.
- Finish Specification: Required finish type, coating or plating thickness, color, gloss, texture, and applicable standards.
- Order Quantities: Prototype quantity, release quantity, annual demand, and expected repeat schedule.
- Documentation Requirements: Required CoC, thickness records, inspection reports, or other quality records.
- Packaging & Delivery: Cosmetic protection, labels, packing configuration, destination, and target delivery date.