FR4 Epoxy Sheet Sizes

FR4 EPGC202 sheets can be supplied in standard panel sizes or cut according to the dimensions required by the customer.

Other sheet sizes, thicknesses and colors can be supplied subject to production and stock availability. Please send the required length, width, thickness, quantity and tolerance when requesting a quotation.

FR4 EPGC202 Technical Properties

The following values are typical test results for reference. Actual values may vary depending on thickness, batch, test conditions and customer specifications.

Physical and Mechanical Properties

Thermal, Flame-Retardant and Electrical Properties

The values above are typical laboratory results and should not be regarded as guaranteed specification limits. Final acceptance requirements should be confirmed in the purchase agreement, drawing or approved technical datasheet.

Main Features of FR4 EPGC202

Flame-Retardant Performance

FR4 EPGC202 is designed for applications where flame resistance is required. Its typical V-0 performance makes it suitable for electrical equipment, control cabinets and insulation components where fire safety is an important consideration.

Excellent Electrical Insulation

The material provides high dielectric strength and reliable insulation resistance. It can be used for electrical separation, high-voltage support components, terminal boards, switchgear insulation and transformer parts.

High Mechanical Strength

The woven glass fiber reinforcement gives the FR4 epoxy sheet good flexural and impact strength. It can serve as both an electrical insulation material and a structural support component.

Low Moisture Absorption

FR4 insulation board maintains stable electrical and mechanical performance in humid operating environments. Its low moisture absorption helps reduce dimensional changes and electrical performance loss.

Dimensional Stability

The laminated structure provides good dimensional stability during cutting, drilling and CNC milling. This makes EPGC202 suitable for precision parts with repeated holes, slots, pockets and contours.

Good CNC Machinability

FR4 EPGC202 can be machined into custom insulating parts using carbide or diamond-coated tools. Correct machining parameters and dust extraction are important for producing clean edges and accurate dimensions.

Chemical Resistance

The epoxy resin system provides resistance to many oils, lubricants and commonly used industrial chemicals. Chemical compatibility should still be tested when the material will be exposed to specific aggressive substances.

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FR4 CNC Machining Services

In addition to supplying full FR4 epoxy sheets, SJ TECH manufactures custom insulation components according to 2D drawings, 3D models or physical samples.

Available machining processes include:

• CNC milling
• CNC routing
• Precision cutting
• Drilling and counterboring
• Slot and pocket machining
• Thread tapping
• Chamfering
• Surface grinding
• Engraving and marking
• Turning of round insulation components
• Prototype and small-batch production
• Medium- and large-volume production

Machining tolerances depend on material thickness, part dimensions, hole diameter, geometry and drawing requirements. Critical tolerances should be clearly marked on the drawing before production.

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Design Recommendations for Machined FR4 Parts

For better machining quality and longer service life, the following points should be considered during part design:

• Avoid excessively thin walls where possible.
• Maintain sufficient distance between holes and sheet edges.
• Use suitable corner radii for internal pockets.
• Clearly identify critical dimensions and tolerance requirements.
• Specify whether burr removal, chamfering or polishing is required.
• Confirm the required material color and thickness.
• Indicate the direction of lamination when it affects performance.
• Provide a PDF drawing together with a STEP, DXF or DWG file when available.

Our engineering team can review drawings before production and recommend suitable machining methods based on the required application.

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Applications of FR4 Insulation Board

FR4 epoxy sheet EPGC202 is used in a wide range of electrical and industrial applications.

Transformers

FR4 can be machined into transformer spacers, terminal boards, support plates, insulation blocks, coil supports and structural insulation components.

Switchgear and Control Cabinets

The material is used for phase barriers, insulation partitions, mounting plates, busbar supports and high-voltage separation components.

Electric Motors and Generators

FR4 insulation board is suitable for slot components, terminal plates, support rings, structural insulation parts and motor assembly components.

PCB and Electronics Manufacturing

FR4 machined parts are commonly used for soldering fixtures, testing fixtures, drilling backing plates, positioning components and electronic assembly tooling.

EV Batteries and Energy Storage Systems

Applications include battery module insulation, cell separation components, electrical support plates, terminal insulation and structural insulating parts.

Industrial Automation

FR4 can be used for sensor brackets, equipment supports, electrical mounting components, inspection fixtures and precision non-metallic parts.

Railway and Transportation Equipment

Its electrical insulation, mechanical strength and flame-retardant properties make it suitable for selected components in railway equipment and industrial transportation systems.

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FR4 EPGC202 Compared with G10 EPGC201

Both FR4 and G10 are glass cloth reinforced epoxy laminates with good electrical insulation and mechanical properties. Their main difference is flame-retardant performance.

Property	FR4 EPGC202	G10 EPGC201
Reinforcement	Woven Glass Cloth	Woven Glass Cloth
Resin System	Epoxy Resin	Epoxy Resin
Flame Retardancy	V-0 Typical	Not Primarily Flame-Retardant
Electrical Insulation	Excellent	Excellent
Mechanical Strength	High	High
Moisture Resistance	Good	Good
CNC Machining	Available	Available
Typical Selection	Flame-Retardant Electrical Parts	General Electrical and Mechanical Parts

FR4 EPGC202 is normally selected when flame resistance is required. G10 EPGC201 may be suitable when high mechanical and electrical performance is required without a specific flame-retardant requirement.

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Quality Inspection

FR4 epoxy sheets and custom-machined parts can be inspected according to the agreed purchase specification and drawing requirements.

Typical inspection items include:

• Length, width and thickness
• Flatness and appearance
• Hole diameter and hole position
• Machining dimensions
• Edge quality
• Surface condition
• Color and material grade
• Quantity and packaging
• Critical dimensional tolerances
• Technical documentation when requested

Inspection reports, material datasheets or relevant test documents can be provided according to order requirements and availability.

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Packaging

FR4 epoxy sheets and machined parts are packed according to their dimensions, weight and transportation method.

Full-Sheet Packaging

• Protective film or paper between sheets
• Waterproof wrapping
• Edge and corner protection
• Reinforced wooden pallet
• Strapping for transportation stability
• Fumigation-free plywood packaging when required

CNC-Machined Parts Packaging

• Individual bags or layered packaging
• Foam or protective separators
• Carton packaging for small components
• Reinforced plywood cases for heavy or precision parts
• Part labels according to drawing number or purchase order
• Customized export packaging available

Proper packaging helps prevent moisture, scratches, edge damage and movement during international transportation.

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Logistics and Delivery

We support international shipping by express courier, air freight, sea freight and railway transportation.

Shipping Method	Suitable For
DHL, UPS or FedEx	Samples and small urgent orders
Air Freight	Medium-volume urgent shipments
Sea Freight	Full sheets, pallets and larger orders
Railway Transport	Selected destinations and consolidated cargo
Customer-Appointed Forwarder	Available

Estimated lead time depends on material availability, order quantity and machining complexity.

• Stock sheet orders: normally arranged after order confirmation
• Cut-to-size sheets: subject to cutting quantity and dimensions
• Simple CNC parts: lead time based on drawing review
• Complex or high-volume parts: confirmed after production evaluation

The final delivery time will be stated in the quotation or order confirmation.

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Why Choose SJ TECH?

• Full-sheet supply and custom machining from one supplier
• FR4, G10, G11, 3240, GPO-3, phenolic and mica materials
• CNC machining according to drawings and samples
• Support for prototypes and batch production
• Dimensional inspection before shipment
• Export packaging suitable for international transportation
• Technical assistance with material selection
• Factory-direct quotation
• Worldwide shipping support

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Information Required for a Quotation

To receive an accurate quotation, please provide:

1. Material grade, such as FR4 EPGC202
2. Sheet size or finished part dimensions
3. Required thickness
4. Order quantity
5. Color requirement
6. Dimensional tolerances
7. 2D or 3D drawings
8. Required test report or certification
9. Packaging requirements
10. Delivery address or destination port

For custom-machined parts, STEP, STP, DXF, DWG and PDF drawings are recommended.

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Frequently Asked Questions

What is FR4 EPGC202?

FR4 EPGC202 is a flame-retardant glass cloth reinforced epoxy laminate used for electrical insulation and structural support. It provides good mechanical strength, electrical insulation, moisture resistance and CNC machinability.

Is EPGC202 the same as FR4?

EPGC202 is commonly associated with FR4-type glass epoxy laminate under IEC grading. However, exact properties and certification requirements should be confirmed with the supplier before ordering.

What is the difference between EPGC201 and EPGC202?

EPGC201 is commonly associated with G10, while EPGC202 is commonly associated with FR4. The primary difference is that EPGC202 is designed to provide flame-retardant performance.

Can FR4 epoxy sheet be CNC machined?

Yes. FR4 can be cut, milled, drilled, tapped, chamfered and ground into custom insulation components. Suitable tools and dust extraction should be used during machining.

Can you manufacture parts according to drawings?

Yes. We can manufacture custom FR4 CNC parts according to PDF, DWG, DXF, STEP or STP drawings. Physical samples can also be evaluated.

Is FR4 suitable for transformer insulation?

FR4 is used for transformer spacers, support plates, terminal boards and structural insulation components. The final material selection should be based on operating temperature, voltage, mechanical load and applicable standards.

What sheet sizes are available?

Common sheet sizes include 1020 × 1220 mm and 1220 × 2440 mm. Other dimensions and cut-to-size panels may be available depending on thickness and production requirements.

Can you supply samples?

Samples can be evaluated according to the required thickness, dimensions and material availability. Machined prototype parts can also be produced based on customer drawings.

What information is needed before placing an order?

Please provide the material grade, thickness, dimensions, quantity, color, tolerance, drawings, packaging requirements and delivery destination.

Are the technical values guaranteed?

The values shown on this page are typical test results. Guaranteed values and acceptance criteria must be confirmed in the approved technical specification or sales contract.