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Vacuum Infusion

Vac GRP is a method for producing GRP components developed by Henleycraft Ltd. The difference between the conventional method of GRP Moulding, hand lay up and Vac GRP is the use of a secondary mould that fits inside the primary mould. A cavity is allowed for in the production of the moulds to the material thickness of the finished moulding.

The advantages of this method are:

• Shorter cycle times, enabling more products to be produced from the same mould in a days production.

• A constant material thickness, allowing 'first fit' of the component without the need to sand varying thicknesses as in hand lay up.

• A smooth finish on both faces of the component, with the option to have a high gloss or textured finish on both faces.

• The ability to incorporate rib, baffles, fixture and fittings in the initial moulding process without the need to secondary bond these fixtures on afterwards.

• A more environmentally friendly process for the operator.

• Less material wastage.

Although the tooling costs are more expensive than conventional Hand Lay Up Moulds, the part price can be considerably less.

Vacuum Infusion Diagram 1
Vacuum Infusion Diagram 2
Vacuum Diagram 3
Vacuum Infusion Diagram 4
Vacuum Infusion Diagram 5
Vacuum Infusion Diagram 6
Vacuum Infusion Diagram 7
The first operation is to apply the Gelcoat.Once the Gelcoat has cured the Fibreglass is loaded into the mould.
The catalysed Resin is the loaded into the mould.
The secondary VacGRP Mould is then inserted into the primary mould.
The vacuum pump is then attached to the mould and air is then drawn out of the cavity between the moulds. The Resin infuses with the Fibreglass as the air is drawn out and left to cure under vacuum.

The VacGRP secondary mould is then released from the primary mould

The completed GRP Moulding is then removed from the primary mould.
The finished moulding with a smooth finish on both faces and a uniform wall thickness.