Machining EP-GC-205

EP-GC-205 (Hgw 2370.4 acc. to DIN 7735, EP GC 205 acc. to EN 60893) is a glass-roving-fabric-reinforced epoxy-resin laminate. It combines very good mechanical and dielectric properties with a limiting temperature of 155 °C (thermal class F) that is significantly higher than standard grades. The coarser roving fabric differs from finer glass fabrics and contributes to the high mechanical and electrical values.

We machine precision parts from EP-GC-205 sheets, round bars and tubes. Sawing, milling, drilling and turning produce clean, dimensionally accurate results with sharp, carbide-tipped or diamond-coated tools, and we allow for the increased tool wear caused by the glass fabric while ensuring adequate dust extraction.

EP-GC-205 is worthwhile whenever elevated operating temperatures occur together with high mechanical and dielectric requirements, for example:

• Electrical insulating parts requiring an elevated continuous-use temperature
• High-strength insulating and partition panels in medium-voltage switchgear technology
• Power-transmission components subject to thermal loading
• Mechanically highly loaded insulating parts in mechanical engineering
• Precision and test engineering requiring low water absorption

The component price is determined mainly by sheet thickness, dimensions, material utilisation (offcuts), machining effort and batch size. EP-GC-205 is priced above standard glass-fabric laminates, since the coarse roving fabric and the resin formulation designed for higher thermal classes require more material effort. We are happy to provide binding prices on request based on your drawing.

EP-GC-205 is not declared for direct food contact. If only the standard limiting temperature of 130 °C is required, EP GC 201 (Hgw 2372) is the more economical choice. If flame retardancy per UL 94 V-0 is additionally required, EP GC 202 (Hgw 2372.1, FR-4) is more suitable. As a thermoset, EP-GC-205 also cannot be reshaped or welded.

An honest assessment, and how the disadvantages can be mitigated in practice:

• Advantage: Very good mechanical strength
• Advantage: Very good dielectric properties
• Advantage: Elevated limiting temperature (155 °C, thermal class F)
• Advantage: Good machinability
• Advantage: Well-proven, temperature-stable material family
• Disadvantage: Not declared for direct food contact
• Disadvantage: Higher price than standard glass-fabric laminates
• Disadvantage: Not flame-retardant treated – for UL 94 V-0, choose EP GC 202 (Hgw 2372.1)
• Disadvantage: Higher tool wear during machining (glass fabric)
• Practical tip: EP-GC-205 is the right choice when elevated operating temperatures occur together with high mechanical and dielectric requirements. If the limiting temperature of a standard grade (130 °C) is sufficient, EP GC 201 is the more economical choice; if flame retardancy per UL 94 V-0 is additionally required, EP GC 202 (Hgw 2372.1) is more suitable.