Get in touch with Zhenling Company
Different starting conditions can create different labor and adhesion risk
Painting Services for CNC Parts
Zhenling’s standard painting service offers solvent-based, water-based and 2K epoxy options, including one-piece minimum-order requests. The written quotation identifies the proposed processing responsibility, coating family and product without asserting a named processor’s credentials or execution site. Send the substrate, service environment, Pantone, RAL or physical color master, gloss target and masking drawing; those inputs allow the proposed processor, coating specification, acceptance method and responsibility split to be reviewed in writing. Painting Services enquiries should include service environment, surface preparation, paint system, film thickness, masking, cure and inspection. Record the proposed route, measurement method, deliverables, exclusions, price basis and schedule in the quotation for the released part, together with every unresolved manufacturing or acceptance assumption.
- Quotation timing confirmed after RFQ review.
- Prototype schedule confirmed after approvals.
- Minimum quantity and single-piece availability confirmed per quotation.
- STEP, IGES, Parasolid, SolidWorks, DWG, DXF and PDF.
Drawings are handled as confidential project files, and a non-disclosure agreement is available on request before commercial review.
//Per quotation
Quote response after usable files and paint requirements arrive.
//Per quotation
Prototype schedule after drawing, color and masking approval.
//1 piece
Minimum quantity confirmed for the quoted painting route.
//3 paint families
Solvent-based, water-based and 2K epoxy options.
//Color approval
Pantone, RAL or an approved physical sample.
//First article
Sample scope, charge and acceptance criteria stated in the quote.
Liquid Painting Capabilities for Custom CNC Parts
Liquid painting runs from sample to production, and custom CNC metal parts can be painted in one-off sample runs or repeat production. The review moves from the drawing outward: substrate and initial surface, preparation, paint family, color, masking, film build, cure constraints, inspection and packaging.
MEASURED COATING THICKNESS
ISO 2808:2019
ASTM D7091-22
SURFACE FINISH REF.
01
Single-Color Finishes
Selected liquid paint is evaluated against the appearance objectives for a matte, flat, satin, semi-gloss and gloss finish, and the approved color reference for the same color target.
- Industrial enclosures and covers
- Visible machined panels
- Brackets, housings and fixtures
02
Multi-Color and Color Breaks
Multi-color work is reviewed when the drawing identifies each color zone, boundary and approval master. Metallic and visually sensitive colors are routed through a finish or first-article sample before repeat production.
- Defined color-break lines
- Revision-controlled artwork
- Visual approval hold point
03
Selective Masking
We review paint-free threads, bores, grounding points, mating faces, datum areas and assembly interfaces. The approved drawing controls the masked boundary and whether a critical dimension is accepted before or after coating.
- Thread and bore protection
- Fit and contact surfaces
- Cosmetic edge control
PROCESS INPUTS
Feasibility starts with usable specification inputs
A color code alone does not specify a production finish. Zhenling confirms each route against the substrate, service environment, paint product or performance requirement, gloss or texture, masked features, dry-film-thickness limits and acceptance plan.
Request Quotation
RESOURCES
Machining and project coordination base
Zhenling was established in 2006 and operates an 8,000 square meter site with a 6,000 square meter workshop. This describes Zhenling’s machining base; the quotation identifies the painting party and execution site. One written order coordinates drawing review, quotation, CNC manufacture, the approved coating route, inspection and delivery.
When liquid painting and powder coating are both under consideration, compare substrate, geometry, masking, heat exposure, color approval and acceptance requirements before the finish route is released. Review the separate powder coating services for metal parts.
Metal Substrates and Paint-System Fit
We review carbon and alloy steels, stainless steels and aluminum alloys for liquid painting. Paint-system fit is confirmed against the exact alloy or grade, initial surface condition, service environment, preparation route and the coating manufacturer’s current technical and safety data. Substrate-dependent adhesion planning also identifies whether ISO 2409:2020 is suitable for the coating thickness, texture and substrate.
Review before painting
Rust, scale, weld spatter, sharp edges, contamination and existing coatings
Specification decisions
Cleaning or abrasive route, edge preparation, primer compatibility, maximum interval to prime
Review before painting
Surface contamination, previous finishing, cosmetic direction and contact surfaces
Specification decisions
Preparation compatible with the grade, adhesion route, masked functional areas, visual master
Review before painting
Alloy, oxide condition, previous conversion or anodic layer, handling marks
Specification decisions
Alloy- and environment-specific pretreatment, primer, paint data sheet and cure constraints
Service-environment inputs
Required inputs include outdoor exposure, chemicals, moisture, temperature, ultraviolet radiation, abrasion and immersion conditions.
- Indoor or outdoor exposure.
- Moisture, immersion or burial.
- Chemical or cleaning-agent contact.
- Operating and cure temperature limits.
- Ultraviolet exposure.
- Abrasion or frequent handling.
- Electrical contact or grounding zones.
- Consumer-facing cosmetic surfaces.
Preparation is part of the coating specification
We define project-specific surface acceptance, cleaning, abrasion or blasting, primer and masking steps around the alloy, service environment and approved paint system. Paint selection is not a substitute for surface preparation. The order review records the actual execution site, applicable jurisdiction and the party responsible for confirming local spray painting, environmental, chemical and product-use requirements.
Specifications
Paint Specification and Masking Requirements
A drawing can identify color yet still omit the controls needed for a comparable quote, so use this Paint Specification & Masking Brief to make the prototype reviewable and production release measurable. Accepted review inputs include a drawing, physical sample, STEP, IGES, Parasolid, SolidWorks, DWG, DXF or PDF package. Written terms must identify who controls and verifies each coat and total dry-film-thickness limits in micrometres and mils.
Engineering release rule One drawing revision must connect the color master, layer build, masked features, measurement method, sampling locations and pass values.
/// Control Variables
- Substrate grade and starting surface condition.
- Service environment and special stresses.
- Paint product, supplier and layer sequence.
- Current technical and safety data sheets.
- Per-coat and total dry-film-thickness minimum/maximum.
- Pantone, RAL or physical color master.
- Gloss, texture and cosmetic class.
- Masking drawing for threads, bores, faces and edges.
- Test method, sampling locations and acceptance values.
- Packaging, assembly and required delivery date.
Control point
Written order requirement
Quote response
Timing confirmed after usable files and paint requirements are reviewed
Prototype schedule
Schedule confirmed after drawing, colour and masking approval
General dimensions & geometry
ISO 2768-1:1989 class m applies to linear and angular dimensions without individual tolerance indications; general geometrical specifications follow ISO 22081:2021 only when invoked by the drawing; coating allowance and masked critical features follow the approved drawing
Dry-film thickness
Approved minimum and maximum for each coat and total build, recorded in µm and mil; the order-selected method is ISO 2808:2019 or ASTM D7091-22
Cross-cut or tape adhesion
ISO 2409:2020 or ASTM D3359-23 only when the order defines method, substrate, location, sampling and pass value
Gloss
ISO 2813:2014 with an agreed 20°, 60° or 85° geometry and suitable surface condition
Instrumental color
ISO/CIE 11664-4:2019 calculations with agreed illuminant, observer, geometry, readings and tolerance
Coated features
Drawing identifies pre- or post-coating inspection, coating allowance and every masked thread, bore, datum, mating or contact surface
/// System Alert
One reading does not define the whole coating
A coating note can state total film thickness and still leave the acceptance procedure incomplete. Coating thickness can vary over a surface, and a single-point measurement does not always represent the coating system, as ASTM D7091-22 notes. State the instrument basis and verification, the number and location of readings, restrictions around edges or curvature, and whether individual coats can be measured or only the completed total.
Get a Paint Specification Review
Pricing Inputs and Lead-Time Commitments
Cost follows the drawing and specification. Quotations account for part size and geometry, quantity, starting surface, preparation route, layer build, paint procurement, color changes, masking load, inspection, cure route, packaging and any expedited scheduling. A low unit-price comparison costs you visibility when preparation, approval, inspection or packaging sits outside the quoted scope.
Quote Normalization and Hidden-Cost Map
01
Surface preparation
HIDDEN BOTTLENECK
HOW TO NORMALIZE
Compare the same cleanliness, roughening, primer and maximum hold interval
02
Paint and colors
HIDDEN BOTTLENECK
Product procurement, minimum pack size and color changes can sit outside a headline price
HOW TO NORMALIZE
Lock product basis, layer count, color references and number of changeovers
03
Masking
HIDDEN BOTTLENECK
Threads, bores, mating faces and color breaks add manual setup and inspection
HOW TO NORMALIZE
Issue the same revision-controlled masking drawing to every bidder
04
Approval hold point
HIDDEN BOTTLENECK
A finish sample or first article can pause production if the owner and response time are undefined
HOW TO NORMALIZE
Name the approver, sample charge, acceptance criteria and release deadline
05
Inspection records
HIDDEN BOTTLENECK
Film-thickness, adhesion, gloss and color checks carry different price and sampling scopes
HOW TO NORMALIZE
Align method, locations, quantity, pass value and required report
06
Packaging and handoff
HIDDEN BOTTLENECK
Cosmetic surfaces can be damaged after acceptance
HOW TO NORMALIZE
Compare protective packing, labeling, assembly interface and delivery term in writing
Quote turnaround
After usable files and paint requirements are reviewed, the written quotation confirms response timing.
Prototype schedule
After drawing, colour and masking approval, the written quotation confirms the painted-prototype schedule.
Order quantity
After quantity, layers, cure and masking load are reviewed, the written quotation confirms minimum quantity, single-piece availability and small-batch or repeat-production schedules.
Schedule boundaries fixed in the quotation
Expedited scheduling is available when the reviewed route can support it; tell us the required date and we confirm feasibility. Payment, delivery terms, the painting party, approvals and handoff points are defined in the written quotation rather than published as a fixed rule.
READY TO START?
Request an Engineer-Reviewed Quote
Quality Control and Coating Acceptance
Convert the approved paint specification into release checks for the quoted route. A method name alone is not an acceptance criterion: identify coating build, texture, substrate procedure, measurement location, test edition and pass value, then confirm the processing and inspection parties and required records in writing.
Specification lock
Drawing revision, substrate, preparation, paint, color, gloss, thickness and masking are finalized.
Sample or first article
The quoted approval piece is reviewed against the agreed visual and measured criteria before release.
Process checks
Defined hold points govern masking, layer build, the cure route and any recorded measurements.
Final release
Incoming and final review use the same written criteria, with agreed records attached when requested.
SYS_CFG // ACCEPTANCE_MATRIX
ISO 2808 / ASTM D7091
Dry-film thickness
Substrate, gage basis, verification, reading plan, locations and min/max values
ISO 2409 / ASTM D3359
Cross-cut or tape adhesion
Applicable coating thickness and texture, substrate procedure, location and pass classification
ISO 2813:2014
Gloss
20°, 60° or 85° geometry, surface suitability, reading plan and acceptance range
ISO/CIE 11664-4:2019
Instrumental color
Master, illuminant, observer, geometry, instrument, locations, formula and tolerance
Records scoped to the order When inspection records or material documents are required, the written quotation must identify their issuer, scope and delivery point. The application-specific acceptance plan sets any required colour difference, gloss range, adhesion classification, corrosion exposure or chemical-resistance result.
Define the Acceptance Plan
Project Workflow and Responsibility
Phase 1
Files received
Drawing, model, revision, quantity and finish requirements enter one review package.
01
Phase 2
Gap review
We return missing paint, color, masking, inspection or schedule questions before quotation.
02
Phase 3
Quote and ownership
The written offer assigns paint procurement, painting party, approvals, tests and handoff points.
03
Phase 4
First-article approval
The finish or part sample is released against the agreed color, appearance and measured checks. Film-thickness records use the order-selected method, such as ISO 2808:2019 or ASTM D7091-22.
04
Phase 5
Controlled production
Masking, application, cure and change control follow the approved route.
05
Phase 6
Incoming and final release
We coordinate review, records, protective packaging and delivery against the written order.
06
Coating Responsibility Handoff Ledger
Zhenling responsibility
Review completeness and route fit across the quotation.
Buyer release input
End-use environment, approved product or performance requirement.
Zhenling responsibility
Review the master, drawing boundary and acceptance hold point.
Buyer release input
Approved sample/code, critical features and authorized approver.
Zhenling responsibility
Retain responsibility for process control and incoming inspection across the quoted painting route.
Buyer release input
Required records, change authority and release deadline.
Zhenling responsibility
Record the site, applicable jurisdiction and verification owner in the order review.
Buyer release input
Product-use or market requirements that apply to the finished part.
Zhenling responsibility
Coordinate disposition against the same written acceptance criteria.
Buyer release input
Approve deviation, rework, remake or specification revision as assigned.
One accountable interface across the quoted route
Written order terms must identify who performs each painting operation, reviews the specification and masking, owns process control and inspection, approves changes and releases each handoff. This page does not assign those responsibilities before quotation.
Liquid Paint Trade-Offs and Alternatives
System Overview: Technical Capabilities & Validation
Liquid paint is useful when a project needs controlled color, a specified liquid coating, selective masking or an appearance route that the approved product can deliver. Liquid paint is not always the lowest-cost route, and 2K epoxy is not always the best system for the service environment. A cross-cut or tape result under ISO 2409:2020 or ASTM D3359-23 is an order-selected adhesion check, not a category-wide environmental performance guarantee.
| Decision Condition | Liquid Paint Review | Alternative or Next Action |
|---|---|---|
| Specified Pantone, RAL, physical master or complex color break | Review liquid paint, sample approval and masking boundary | Compare only after the same color and approval plan is quoted |
| Drawing explicitly requires a powder system | Do not substitute a liquid system by assumption | Quote powder coating or request written engineering approval for a change |
| Aluminum needs an integral oxide finish | Paint remains a separate applied layer | Review anodizing or a combined route against alloy and appearance requirements |
| High corrosion, immersion, chemical or temperature demand without a validated system | Do not promise a category-wide performance number | Select and validate a product/system against the actual environment before release |
| Part size or cure requirement falls outside the reviewed route | Feasibility stays open until the route and execution site are confirmed | Use a qualified finishing partner or redesign the finishing sequence |
| Critical fit leaves no allowance for coating build | Use coating allowance and selective masking where feasible | Move the acceptance condition, machine after coating, or choose another finish |
Engineering Tools & Calculators
01
Paint Specification Checker
02
Quote Scope Normalizer
03
DFT & Layer Build Calculator
CNC Part Painting FAQs
Which CNC metals can you review for liquid painting?
We review carbon and alloy steels, stainless steels and aluminum alloys. Approval depends on the exact grade or alloy, initial surface, preparation route, selected paint data and service environment.
Do you offer solvent-based, water-based and 2K epoxy paint?
Yes. We review all 3 options, then confirm the product, layer build, cure condition and acceptance plan in the quotation rather than ranking one family as universally best.
Can you match Pantone, RAL or a physical color sample?
Yes. Send the Pantone or RAL reference or an approved physical master, plus gloss or texture. Instrumental color acceptance also needs illuminant, observer, measurement geometry, reading plan and tolerance under the agreed method.
Can you mask threads, bores and mating surfaces?
Yes, when the approved drawing identifies every paint-free thread, bore, datum, mating face, grounding point and color-break boundary. It must also state whether the affected dimension is accepted before or after coating.
What paint specification should I send with my drawing?
Send substrate and surface state, environment, paint product or system, technical and safety data, each-coat and total DFT min/max, color master, gloss/texture, masking, test and sampling plan, packaging and required date.
How do you define dry-film thickness and coating allowance?
State minimum and maximum thickness for each coat and total build in µm and mil. Add the method, gage basis, locations, reading count, edge or curvature rule, and drawing allowance for every coated or masked critical feature.
Which coating inspection methods can be specified?
Orders can invoke ISO 2808:2019 or ASTM D7091-22 for thickness, ISO 2409:2020 or ASTM D3359-23 for cross-cut/tape adhesion, ISO 2813:2014 for gloss and ISO/CIE 11664-4:2019 for CIELAB calculations. The order still defines applicability, sampling and the pass value.
Do you accept one-off painted CNC parts?
Minimum quantity, single-piece availability, sample charges, approval criteria and any credit treatment are stated in the written quotation.
How quickly can I receive a quote and painted prototype?
After usable files, paint requirements, drawing, colour and masking are reviewed, the written quotation confirms response timing and the painted-prototype schedule.
Can I request a first article, finish sample or NDA?
Yes. First-article or color/finish approval samples are available, with charge and acceptance criteria defined in the quote. NDA terms may be reviewed before protected files are exchanged.
When should I choose liquid paint instead of powder coating?
Review liquid paint when the drawing specifies a liquid system, controlled color or appearance, selective masking or a product-specific coating route. Review powder or another finish when the drawing, cure constraints, coating build or service requirement points elsewhere; compare them on the same preparation, inspection and packaging scope.
RFQ Handoff: Send Your Paint Specification and Drawing
An incomplete RFQ creates a release gap between the quoted finish and the finish you intend to approve. Attach the current revision, quantity, material, service environment, paint system, color master, gloss or texture, DFT minimum/maximum, masking drawing, acceptance methods and required date; if the order invokes ISO 2409:2020, ASTM D7091-22 or another test method, include the sampling locations and pass values as well. Accepted file formats include drawings, physical samples, STEP, IGES, Parasolid, SolidWorks, DWG, DXF and PDF.
Request a Painting QuoteAfter the usable file package and paint requirements are reviewed, the written quotation confirms response timing. If a non-disclosure agreement is executed, it governs the information covered by that agreement.
Paint Specification Review
Receive a list of missing product, film-build, test or release inputs before the route is quoted.
Masking & Color Feasibility
Receive the drawing and master-sample questions needed to confirm boundaries and approval steps.
References & Sources
- ISO 2808:2019 — Paints and varnishes: determination of film thickness
- ASTM D7091-22 — Nondestructive measurement of dry film thickness on metal substrates
- ISO 2409:2020 — Paints and varnishes: cross-cut test
- ASTM D3359-23 — Rating adhesion by tape test
- ISO 2813:2014 — Gloss value at 20°, 60° and 85°
- ISO/CIE 11664-4:2019 — CIE 1976 L*a*b* colour space
- ISO 2768-1:1989 — General tolerances for linear and angular dimensions
- ISO 22081:2021 — General geometrical and dimensional specifications
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