Spraying method
At spraying method a fiber-glass filament is delivered to the gun cutters, where it is cut in short fibers. Then in the air short fibers are mixed with a stream of resin and catalytic agent and applied on the mould. After chopped roving application it is to be rolled on to remove air pockets from laminate. Rolled-on material is left for cure at ordinary atmospheric conditions.
Materials applied:
- RESINS: polyether mainly.
- FIBERS: only fiber-glass filament in the form of roving.
- FILLING MATERIAL: any, styrol-proof (placed manually).
Main advantages:
- It is widely used for many years.
- Fast application of fibers and resins.
- Cheap moulds.
Main disadvantages:
- Laminate tends to be rich with resin and therefore it is too heavy.
- There are only short fibers which limited mechanical characteristics of laminate.
- Resins shall be of low viscosity to provide its spraying (it causes its mechanical characteristics and heat-resistance reduction).