Tuesday 29 July 2014

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).

Sunday 13 July 2014

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

Tuesday 8 July 2014

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.