Preparations For Turning Over The Hull

Today I finished the aft-side turning wheel. The bow-side wheel is already in progress and will be finished this weekend (hopefully).

Glass Coating

As already mentioned the hull is coated by stitched biaxial fibreglass of 600 g/m² weight.

These non-crimp fabric combine two layers of unidirectional fibres ±45° which are stitched together using a light thread. The result is an engineered biaxial fabric with predictable, repeatable properties.

The pre-cut fabric is spread on the surface prewetted with epoxy. One must be very careful to avoid fiber breakage.



After the fabric is laid-out, it is impregnated with epoxy. About 0.7 kg/m² epoxy is required.

The epoxy is spread by using a "Fliesengummi" (Tilers use it for grouting their tiles)



Finally comes a layer peel-ply (Release Fabric) on the fresh FRP layer. Peel-ply, is a tough, finely woven nylon fabric treated with a release agent.  It is  used to protect the lay-up from contamination. Another advantage: It is no sanding for next layer required.

Right: naked epoxidized fibreglass
Left: epoxidized fibreglass covered by peel-ply

Preparing Glass Coating

The epoxy impregnation of the hull has been finished and I already started sanding the surface to prepare the glass coating.

 

The hull is coated by stitched biaxial fibreglass +/-45°, 600 g/m².
The designer Dudley Dix requires just 450 g/m² at mast step area as shown in sketch bellow. But I think a stiffer hull and harder surface is worth the higher effort.