Epoxy Flat Plate Sheet FR-4 Thick=1~8mm Green FR-4 Epoxy Plate Fiberglass Sheet

For light-duty insulation panels inside control cabinets or relay boards, 1–2 mm is typically sufficient. If the panel also needs to bear mechanical load or resist flexing under fastener torque, 3–5 mm provides a better safety margin. For structural mounting plates that also serve as insulators, 6–8 mm is appropriate.

FR-4 has a tensile strength typically in the range of 270–310 MPa and a flexural strength of approximately 415–550 MPa, making it suitable for light structural applications such as jig plates, fixture bases, and mounting brackets in electronics assembly environments. It is not a substitute for metal in high-load or impact-prone applications.

FR-4 has low moisture absorption (typically <0.10% by weight per IPC-4101 standards), which means its dielectric properties and dimensional stability are well-maintained in humid conditions. It is not waterproof for immersion use, but performs reliably in typical workshop, enclosure, and indoor industrial environments.

Yes. FR-4 can be cut with a carbide-tipped router bit, scored and snapped for straight cuts on thinner sheets (1–2 mm), or drilled with standard HSS or carbide drill bits. Use moderate feed rates and avoid overheating the material. A dust mask is recommended when machining, as fiberglass dust is an irritant.

Yes — FR-4 is the base substrate used in the vast majority of rigid PCBs. These flat plates are the same material without copper cladding, making them useful as bare insulating substrates, spacers, or prototype bases where you need the mechanical and electrical properties of PCB material without the copper layer.

Choose based on the footprint of your application. The 100×100 mm plates suit compact insulation inserts, small jig plates, and PCB-scale spacers. The 150×100 mm and 150×200 mm plates are better for larger relay panels, bus bar separators, or fixture bases that need more surface area. If you need a custom size, these plates can be trimmed down with standard tooling.

Standard FR-4 maintains its mechanical and electrical properties from approximately -50 °C to +130 °C (continuous). Short-term excursions up to the glass transition temperature (~130–140 °C) are tolerable, but sustained exposure above Tg will cause softening and dimensional change. For higher-temperature applications, consider high-Tg FR-4 or alternative laminates.