Hand Layup


Detail Hand Lay-up

Some parts require fine detail work or insertion of components where the glass & resin matrix is applied by hand. This is usually employed on smaller parts, short run or moulds that are used infrequently. Higher volume parts with more complex laminates benefit from RTM infusion technology. Hand lay-up usually incorporates template cut or machine cut glass stack. The use of pre prepared and known glass weight mat produces a part of predictable thickness, weight and properties. This consistency is the strength of hand lay-up and why it is often chosen for specialist parts and short to medium run where weight is a critical factor.

Summary

In brief the glass fibre reinforcement is placed wet out with catalysed resin and manually placed into the mould and shaped to fit using brushes and rollers. In this process visual inspection and experience deliver precise resin to glass ratio providing excellent control of mechanical properties, predictable and uniform laminate thickness and good back surface finish which can be improved by use of finer woven cloth or tissue.

Hand-laup permits the use of many different resin systems including polyester, vinyl-ester, epoxy, terepthalate and more. Additional advantages include ability to be flexible with part inclusions. The interior surface can be of superior finish and if required, can be flow-coated, a process where a catalysed and waxed gelcoat is painted or sprayed on the back of the laminate producing a smooth colour (not moulded) finish. The process produces products of uniform, predictable physical properties and very accurate laminate thickness.

Quality

As stated above the laminate resulting from hand layup allows good control over glass placement and the resin:glass ratio providing parts of optimum strength and strength or inserts in specific areas. From an engineering perspective the resin matrix is primarily used to hold the glass reinforcement in place. While the resin is relatively flexible the glass is rigid with high tensile properties. The more accurate the use of resin and the better located and tightly packed the glass matrix, the more mechanically efficient the reinforcement.

Features

Depending on the complexity of the part more than one item per shift can be obtained from the one mould. Excellent quality finish can be achieved the exterior mould surface and the interior face can be finished in various stages from raw laminate to tissue and flowcoat or resin rich for potable water or other sensitive applications.

Inclusion of other components such as timber, metal, plastic or foam core etc can be done during the production cycle.

Benefits

For the client, the primary benefits are part uniformity and consistent production. Known structural laminate components and detail can be included in production for a well engineered part. 

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