Machining HGW 2372.1

Fabric-based laminates (HGW) belong to the industrial laminates: fabric layers are impregnated with a thermosetting resin and pressed under heat and pressure into sheets, round bars or tubes. For HGW 2372.1, the reinforcing fabric is glass fabric and the binding resin is an epoxy resin – known worldwide primarily under the name "FR-4", the standard material of the PCB industry. Compared with cotton-fabric laminates such as HGW 2282.5, the combination of glass fabric and epoxy resin yields significantly higher strength, lower water absorption and better fire behaviour (UL 94 V-0); the colour is characteristically light green.

HGW 2372.1 machines well – 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. During machining we ensure adequate dust extraction. This allows us to reliably manufacture high-strength, flame-retardant insulating parts, from single items to series production.

HGW 2372.1 is worthwhile whenever high mechanical strength must be combined with good electrical insulation and flame retardancy – for example:

• PCB substrate and electronics manufacturing (FR-4)
• High-strength insulating and partition panels in medium-voltage switchgear technology
• Components requiring flame retardancy (UL 94 V-0), e.g. in aerospace and rail technology
• Mechanically highly loaded insulating parts in mechanical engineering
• Precision and test engineering requiring low water absorption

HGW 2372.1 is an engineering laminate; the price depends on the semi-finished shape (sheet, round bar, tube), dimension, material utilisation (offcut), machining effort and lot size. HGW 2372.1 is priced above cotton-fabric laminates such as HGW 2282.5, since glass fabric and epoxy resin require more material effort. We are happy to quote binding prices on request based on your drawing.

Equally important are the limits of the material:

• Direct food contact – HGW 2372.1 is not declared for this
• Pure cost optimisation without increased mechanical or electrical requirements – a cotton-fabric laminate such as HGW 2282.5 is sufficient here
• Continuous use above approx. 130 °C (thermal class B)
• Reshaping or welding – not possible as a thermoset (machining only)
• Skin-sensitive applications without protective measures during machining (glass fibre dust)

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

Disadvantages:

Practical tip: HGW 2372.1 is the right choice when high strength, low water absorption and flame retardancy are required – for example for PCB substrates or highly loaded insulating parts. If the strength of a cotton-fabric laminate is sufficient, HGW 2282.5 is the more economical choice.

• Very high mechanical strength
• Low water absorption
• Flame-retardant (UL 94 V-0)
• Very good electrical insulation properties
• World-standard material (FR-4)
• Not declared for direct food contact
• Higher tool wear during machining (glass fabric)
• Higher price than cotton-fabric laminates
• Continuous use limited to about 130 °C
• Tracking resistance (CTI 220) may be insufficient for very high medium-voltage requirements – check melamine-resin-bonded grades such as HGW 2282.5 in that case