Process
The resin and fibre reinforcements containing a temperature-activated catalyst are placed in matched metal moulds mounted in a hydraulic or mechanical moulding press. The mould halves are heated to temperatures ranging from 150 to 160 degrees Celsius and a pressure of approximately 1000 psi is applied. While the mould remains closed, the thermosetting material undergoes a chemical change (cure) that permanently hardens the shape in the mould cavity. Moulding closure times vary from about 30 seconds to several minutes, depending on part design and material formulation. When the mould opens, parts are ready for finishing operations such as de-flashing, painting, bonding, and installation of inserts for fasteners.
Materials Options
Resins: Thermosetting materials such as SMC (sheet moulding compound), BMC (bulk moulding compound)
Advantages
- The process yields two excellent finished surfaces and outstanding part to part repeatability
- Trimming and finishing costs and time are minimal
Limitations
- Unsuited to complex designs
- Low cost effectiveness for small runs
- Susceptible to breakage when the finished item is removed from the equipment
- Process duration
Applications
- Lightly loaded structural panels, e.g. caravan bodies, truck fairings, bathtubs, shower trays, some small dinghies.