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Surface Finishing

E-Coating
Services

Electrocoating (electrophoretic deposition) delivers pinhole-free, ultra-uniform primer coverage on every surface — including recesses, seams, and interior cavities — providing the industry benchmark in corrosion protection.

Cathodic Electrophoretic Deposition HXCNC
ISO 9001:2015ASTM B117Zero VOC
E-Coat
Cathodic Electrophoretic Deposition
15–35μm
Film Thickness
500+h
Salt Spray Resistance
100%
Surface Coverage
5–7 Days
Lead Time
Cathodic vs. Anodic E-Coat

We primarily operate cathodic ED (CED), the automotive and industrial standard offering superior corrosion resistance and throwing power.

Cathodic E-Coat (CED) — Recommended

The part acts as cathode. Resin deposits with superior corrosion resistance, excellent throwing power into cavities, low VOC. Industry standard for automotive, appliances, and industrial parts.

500+ hr NSSLow VOCFull Cavity CoverageAutomotive Grade

Anodic E-Coat (AED)

The part acts as anode. Suitable for aluminium, brass, and zinc substrates where anodic dissolution on steel is acceptable. Used for decorative and lower-corrosion applications.

Aluminium CompatibleDecorativeNon-ferrous

E-Coat + Topcoat System

E-coat primer combined with powder coat or liquid topcoat for applications requiring both complete cavity coverage and specific colour or texture finish requirements.

Best CorrosionColor AvailableFull System
E-Coating Process Steps

A fully automated, closed-loop process ensuring consistent film build, complete surface coverage, and minimal solvent emissions.

01

Phosphate Pre-Treatment

Multi-stage zinc or iron phosphating plus DI water rinse creates a conversion layer that maximises adhesion and corrosion resistance under the e-coat film.

02

Electrophoretic Immersion

Parts fully immersed in water-based paint tank. DC voltage drives ionic resin particles to deposit uniformly on every surface including cavities and welds.

03

UF Rinse & Curing

Ultrafiltration rinse recovers excess paint. Parts baked at 160–185°C for 20–30 minutes to crosslink the deposited film into a durable, smooth continuous coat.

04

Inspection & Testing

Film thickness (DFT), salt spray, cross-hatch adhesion, and visual inspection for pinholes, craters, and surface defects per ASTM B117.

Process Specifications

Coating Parameters
Film Thickness15 – 35 μm
Resin TypeEpoxy / Acrylic (water-based)
Cure Temperature160 – 185°C
Throwing PowerExcellent — full cavity coverage
Colour OptionsBlack / Grey / Custom
Performance Standards
StandardASTM B117 / ISO 9227
Salt Spray (unscribed)> 500 hours
AdhesionClass 0 (ISO 2409)
SubstratesSteel, Cast Iron, Al, Zinc
Max Part Size1500 × 800 × 600 mm
Industry Applications

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Automotive Body Parts

Car bodies, doors, chassis, and structural stampings — e-coat is the OEM primer of choice for complete cavity coverage.

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Motorcycle & Bicycle Frames

Tubular structures with internal passages requiring full interior and exterior corrosion protection in a single process step.

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Appliances

Washing machine drums, refrigerator cabinets, and HVAC components requiring pinhole-free consistent primer coverage.

⚙️

Agricultural Equipment

Frame weldments, brackets, and structural components for tractors and implements in harsh outdoor environments.

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Hardware & Fasteners

High-volume fasteners, hinges, and stampings requiring uniform thin-film primer at production speed and low cost.

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Industrial Fabrications

Welded assemblies and enclosures where weld seams and joints require complete primer penetration for maximum protection.

Key Advantages

100% Surface Coverage

E-coat penetrates seams, welds, blind holes, and internal cavities — impossible to achieve with spray painting or powder coating alone.

Zero VOC Waterborne Process

Water-based system with <1% VOC content. No solvent emissions — compliant with the strictest environmental and workplace safety regulations globally.

Self-Limiting Film Build

The deposition process self-limits at target thickness, preventing excess buildup and ensuring batch-to-batch consistency throughout the production run.

High-Volume Production Efficiency

Automated continuous line handles high volumes consistently. 95%+ paint utilisation through ultrafiltration rinse recovery system.

Frequently Asked Questions

Everything you need to know before ordering. Contact our team →

E-coating (electrophoretic deposition / CED) immerses parts in a water-based paint bath and uses DC voltage to drive paint particles onto every wetted surface. Unlike spray painting, it provides 100% coverage including internal cavities, welds, and recesses. The self-limiting nature of the process also gives extremely uniform film thickness (±2–3 μm) impossible with spray methods.
Yes — this is e-coat's primary advantage over all spray-based processes. As long as bath solution can enter and drain from a cavity, e-coat will deposit uniformly on all interior surfaces. This is why it is the standard primer for automotive body-in-white, bicycle frames, and agricultural equipment with complex welded box sections.
E-coat is predominantly available in black and grey. Colour e-coat systems exist but require separate dedicated tanks for each colour, making colour changes economically viable only at very high volumes. For colour requirements, we recommend e-coat as a primer followed by powder coat or liquid topcoat in your desired colour.
E-coat provides comparable or better corrosion resistance to powder coating on flat surfaces (500+ hours NSS), but significantly outperforms powder coating on complex assemblies with seams, welds, and cavities where spray-applied powder cannot reach. E-coat primer plus powder coat topcoat is the gold standard for maximum system corrosion protection.
Our e-coat tanks handle parts up to 1500 × 800 × 600 mm. For larger assemblies such as vehicle frames or major structural components, please contact us with your dimensions. Part weight is also a consideration for handling and racking design.
Yes. E-coat is one of the most environmentally friendly industrial coating processes available. It is water-based with <1% VOC content, produces minimal waste through the UF rinse system (95%+ paint utilisation), and generates no hazardous solvent emissions during application or curing.
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Send Your Drawing.
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Every enquiry includes a DFM review — tolerance feasibility, material confirmation, and process approach confirmed before production starts. MOQ 1 piece.

24hr
Quote Response
MOQ 1
Prototypes OK
ISO
9001:2015
📐
DFM Review on Every Enquiry
Tolerance feasibility, fixturing strategy, and material confirmation. Specific, actionable feedback — not generic pushback.
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First Article Inspection — Standard
FAI report on every new run. Material certs and surface treatment certs included with every shipment.
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Same Process: Prototype to Production
Process plan from your prototype applies to production batches. No re-qualification when you scale.
3 / 4 / 5-Axis CNC + Turning
Complex structural parts, shafts, housings, and transmission components. Metals and engineering plastics.
ISO 9001:2015 3/4/5-Axis Milling CNC Turning CMM Inspection Global Delivery