The next stage is to laminate over the joins
where the deck was cut away.
Start by carefully feathering the edges
on both sides, ideally with a taper of
around 12:1. For a 4mm thickness of GRP
that would give a width of around 50mm
each side. Then cut lengths of fibreglass
tape into varying widths to fill the
depression, starting with the narrowest
section of tape on the bottom.
Laminate these in place with just
enough resin to thoroughly wet out the
tape, using a consolidating roller to
ensure you don’t trap too much resin in
the laminate.
It’s generally easy to see when there’s
not enough resin used – as white glass
fibres will be visible. It’s these that
eventually turn yellow in structures that
have not been properly wetted out.
However, it’s not quite so obvious when
too much resin is used. The problem with
this is that the structure is weaker and
more brittle than it would be with optimum
wet out.
At this point you won’t have a smooth
surface ready for painting. The first stage
is to knock off any high spots, ideally with
a coarse sanding disk in a grinder. Andy
then used epoxy thickened with silica to
create as smooth a surface as possible
before final fairing. This is a cheaper
option than microballoons, but they’re
easier to sand – so you might want to
consider mircroballons if there’s a lot of
sanding to be done.
If there are large areas at slightly
different levels, the filler can be applied
using a notched scraper, which reduces
the time needed for sanding.
It’s then a process of filling and sanding
until the surface is sufficiently smooth.
Finally, priming then painting with several
coats of KiwiGrip will give an excellent
non-slip surface that will help to hide any
small imperfections.
15
One side finished! Now the joins
where the laminate was cut away
have to be sealed and strengthened, but
first they have to be ground to a taper.17
Laminating complete, ready for the
high spots to be sanded back.16
The tapered indent is then filled
with strips of glassfibre tape and
resin, applied and consolidated in layers
until flush with the original surface.18
Applying filler to the join for the first
stage of fairing.REPAIR CORED DECKS
Final laminating
Fairing and painting
The surgery may
have appeared
traumatic at the
time, but once
faired and painted
La Rochelle’s
coachroof looks
as good as new