Yacht paints and
coatings
1.Surface Preparation for yacht paints on Bare
GRP
All fibreglass substrates should be thoroughly
degreased and cleaned, to remove traces of mould release
agents that may be present with a suitable surface
cleaner. The surface should then be lightly sanded with
medium to fine abrasive paper to provide a keying pattern
for the subsequent yacht coatings, the substrate should
then be thoroughly wiped to remove any dust.
Previously coated surfaces -
Topsides
If the existing marine coatings are in good
condition and adhesion is still good, proceed with
thoroughly degreasing and cleaning the existing coating
followed by sanding with medium to fine abrasive paper
(180-240). Thoroughly remove all dust and sanding
residuals before starting the paint application. Apply
undercoat and topcoat as required.
If the existing yacht paints and coatings are in
poor condition, cracking or flaking paint, then it is
necessary to remove the old paint with either a remover
or by scraping or sanding. And then proceed with the
preparation as described for bare substrates.
Previously coated surfaces -
Below the waterline
If the existing coating is in good condition, it
is generally enough to remove any powdering or
loose parts
of the old antifouling, by sanding with a fine abrasive
paper and applying 2 coats of the new antifouling
compatible with the existing one. if the type of
antifouling is unknown it is recommended to apply 2-3
coats of solver primer intermediate undercoat before
applying the new antifouling.
If the existing hull coating is in poor
condition, cracking flaking and loss of adhesion from
substrate it is necessary to remove the old antifouling
with a suitable antifouling remover or by sanding with
medium abrasive paper, thoroughly remove all dust from
the substrate. Then proceed with preparation as described
for bare substrates.
2.Surface preparation for boat paints on Bare
Steel
The surface preparation of steel before applying
an anticorrosive coating system is very important and
could directly affect the life/adhesion of your marine
coating system.
The steel surface should be free from rust,
corrosion and traces of oils, the best method of surface
preparation is to carry out adequate shot blasting in
accordance to SA2.5 standard if this is not possible it
will be necessary to prepare the surface by using
grinders, wire brushing and sanders to remove any traces
of rust from the substrate, before the application of a
coating system. If the substrate has been shot blasted,
the application of EPOZINC (zinc-rich, cold galvanising
primers) is recommended, giving a high quality
anticorrosive barrier. The recommended coating system for
below and above the water line in either one or two
component should then be applied.
Previously coated surfaces -
Topsides and below the water line
If the existing paint is in good condition and
there is no rust, cracking or bubbles within current
paint-work, then it is recommended to thoroughly clean,
degrease and sand the surface with a medium-fine abrasive
paper removing any dust and sanding residue from
the surface. After the preparation has been carried out
it will be suitable to apply your preferred coating,
undercoat and topcoat system or protective coating and
antifouling system.
If the existing coating is in poor condition, if
there is rust showing, flaking, cracking, loss of
adhesion from the substrate it is recommended to remove
the old coating by mechanically sanding, shot blasting or
with a remover and proceed to prepare substrate as
described for bare substrate.
3.Surface preparation for boat paints on wood
Bare substrate
The wood should be thoroughly cleaned and
degreased to be free from traces of oil and grease, which
may be present especially with oily woods. Sand the wood
with a medium-fine abrasive paper in order to provide a
rough pattern that allows a keying for the subsequent
coating system. All dust and sanding residuals should be
thoroughly removed from the substrate by brush and vacuum
cleaner. Clean the surfaces with a cloth soaked with
Thinner 203, allowing to dry fully before applying the
recommended coating system.
If the paint is in good condition, with no
cracking, blisters, flaking or loss of adhesion then
it will be possible to clean and degrease the existing
coating and sand with a medium-fine abrasive paper taking
care to remove all dust and sanding residue from the
surface before starting the paint application. After this
has taken place proceed with the application of suitable
undercoat and topcoat.
If the paint is in poor condition, flaking loss
of adhesion, cracking, then the coating should be removed
back to the bare wood either by a remover or by sanding
and scraping, taking care to remove all the dust and
sanding residue from the surface. It is important then to
follow the recommended coating system for bare wood. Like
with any substrate it is important to make sure that the
surface preparation is carried out and suitable primers
applied to gain a long lasting finish.
Previously painted substrates -
Below the waterline
If the paint is in good condition and a new
application of yacht antifouling is required, it is
suitable to sand the existing coating with a medium
abrasive paper ensuring that there is no marine growth
and flaking or loss of adhesion. After removing all
sanding residue from the substrate, apply 2 coats of
antifouling. If old antifouling is unknown it is
recommended to apply 2-3 coats of Solver primer before
the application of the new boat antifouling.
If the old paint is in poor condition, loss of
adhesion, cracking then it is important to remove the old
coating from the substrate by using a remover or by
sanding and scraping back to the bare wood removing all
sanding residue from the surface. It is important to use
the recommended coating systems for all types of boat
construction especially wood, taking acre to use suitable
primers below the waterline, achieve a barrier before the
application of antifouling. Antifouling is only a
protection from marine growth/fouling.
Boat Varnishes
There is nothing more eye catching then
perfectly varnished wood, enhancing the natural colour
and the beauty of the wood, but also adding protection
from the severe marine environments. The surface
preparation of wood before varnishing is important not
only to achieve a long lasting finish but the clear
nature of varnish will show any area of the wood which is
in poor condition or which has not been prepared
properly.
Surface preparation for yacht varnishes on Bare
wood
The wood should be thoroughly cleaned and
degreased to be free from traces of oil and grease which
may be present especially in oily woods. Sand the wood
with a medium-fine abrasive paper in order to provide a
rough pattern that allows a keying for the subsequent
coatings system. All dust and sanding residues should be
thoroughly removed from the substrate by brushing and
vacuuming. Clean the surface with a cloth soaked with
Thinner 203, allowing to dry fully before applying the
recommended varnishing system. When priming wood with
varnish depending on the Skipper's Line
varnish which is used, dilution of the varnish with the
appropriate thinner will aid the penetration of the
varnish enabling better adhesion to the
substrate.
Previously varnished
surfaces
They may be different reasons as to why you need
to re-varnish.
A. The varnish is crazing, showing loss of
adhesion, UV damage to the wood resulting in loss of
colour
or
B. Simply good maintenance on your behalf by
wanting to apply a fresh coat of varnish.
if the reason is B, it will be suitable to sand
the existing varnish with a fine abrasive paper and
thoroughly clean and degrease the surface, removing all
dust and sanding residue. Proceed with the
application of a varnish compatible with the pre-existing
one, if the varnish is unknown then it is recommended to
remove the varnish back to bare wood or to do a test
patch to see if the varnish is compatible.
If
the reason is A, varnish is crazing, cracking, coming off
or has lost its colour, then it is recommended to remove
the old varnish back to bare wood, by using a remover or
by sanding and scraping the varnish, making sure that the
surface has been thoroughly cleaned and degreased.
Proceed by following the surface preparation for bare
wood and follow up with recommended varnishing
system.
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