249 37 14MB
English Pages [142] Year 1996
/
THE INTERNATIONAL MARINE SAILBOAT LIBRARY
SAILBOAT HULL & DECK !T
^r
REPAIR
H^
DON CASEY
i.
THE INTERNATIONAL MARINE SAILBOAT LIBRARY
SAILBOAT
HULL & DECK REPAIR DON CASEY
S=-
m
^
INTERNATIONAL MARINE CAMDEN, MAINE
Public Llbrarj'
^ \.
c^.
Saiisaulo. California
949
)5
M.
CONTENTS
Introduction
4
Leaks
6
Choosing a Sealant
8
Rebedding Deck Hardware Preparing a Cored Deck for
30
Understanding Polyester Resin
66
Sanding
34
Grinding
69
Scratch Repair
36
The
15
— ATennporary 17
Rebedding Deadlights
18
Replacing Portlights
21
Mast Boots
24
Hull-to-Deck Joint
24
Centerboard Trunks
27
Through-Hull Fittings
27
Pressurizing to Find Leaks
29
Deck Repairs
40
Stress Cracks
42
Voids
45
Crazing (Alligatoring)
47
Renewing Nonskid
51
Teak Decks
55
Is
Essential
Basics of Fiberglass Lay-up
When 14
Solution
64
32
New
Sealing Chainplates
Laminate Repair
Buffing
10
Hardware
Sealing Portholes
Restoring the Gloss
to Use
Epoxy
70
74
M.
^)
f mr^
f0k
^. ' /
-4^
/
/
mS^ %r\^ Core Problems
78
Hull Repairs
92
Delamination
80
Gouges
94
Wet Core
82
Blisters
98
Damaged Core
85
Impact
Reinstalling the Skin
87
and Rudder Damage
Keel
Weeping
Strengthening
89
Stiffening a Skin
90
Damage
104
116
Keel
Keel/Centerboard Pivot Problems Hull
Damage Around
119 Fins
and Skegs
Damaged Rudder Blade/Shaft
Movement
External Ballast
Index
114
120 121
123
124
126
Copyright Information 134
—
INTRODUCTION: BEAUTY
MORE THAN
IS
Likewise molded glass-reinforced plastic boats.
Fiberglass.
Legendary yacht designer L Francis Herresiioff has
— somewhat inelegantly,
it
seems to
me
but
how many of Herreshoff's
boats have ended up as lobster condominiums or fuel for a
the
boat shed stove, while snot-built boats of
same
how
age, no matter
undeserving of
and estuaries? Wooden boats
regularly die
early deaths of natural causes; fiberglass boats
particular
I
wooden boats, and in Herreshoff's wooden boats. There is
love
decades.
much
to is
love
I
material of
If
you want
a boat to display,
recommend
it,
many boatowners to conclude that
often low,
difficult.
elicits
Any
we hope to quell
pages that
The craftsmanship of the builder
is
obvious:
pound
curves, knees cut
harness the tree's joints
wedding
evident
a natural
crook to
a thick layer of fiber
and
craft
a
is
far less
boat-shaped
sticky glop.
the dried glop pops out of the mold with the graceful curves yields
But
it
isn't
perspective. in
no redemption.
redemption that If
That
same
we open
is
called for;
china.
yachts,
Why
not
the leaded glass doors
we are likely to encounter fine wooden plates, woven bowls?
Because china dishes forced clay
—
a can of gelcoat paste or a bit of glass cloth resin
and give
it
a whirl. You'll
is
buy
to
and
wonder what you
were worried about. this
book
is
confined to
repairs to fiberglass boats,
it is
hull
glass repairs. Fiberglass boats are not
Decks, for example, balsa, or
foam,
may be cored
railed
and deck
not limited to fiberall
fiberglass.
with plywood,
with aluminum, covered with
teak, outfitted with bronze, interrupted with acrylic, it's
the galley of one of Mr. Herreshoff's classic
wooden
way you can
purge yourself of any nagging doubts
While
strength, precise dovetail
and beam. Such
formed by painting
in a hull
mold with
full
shelf
from
com-
fol-
the skeptics with astound-
fully
planks steamed to linguini and worried into
repair
assertion to the contrary too
raised eyebrows. In the
and manipulating boat.
fiber-
A lesser-known virtue of fiberglass is that it is repair. A fiberglass hull's seamless nature
ingly clear explanations, but the only
into the flowing contours of a
has
easy to
something magical about taking straight lumber it
wood
but for a boat to use,
hard to beat.
must be
me wrong;
malleable, durable, and easy to
choice for boat construction for more than three
leads
must be assassinated. Don't get
is
made fiberglass the overwhelming
glass
immortality, continue to ply the world's oceans, bays,
Fiberglass
maintain. These characteristics, widely known, have
Maybe beautiful wooden
called this versatile material "frozen snot." so,
SKIN DEEP
molded bone-rein-
— are infinitely more serviceable.
penetrated with stainless rubber. Virtually
all
steel,
of these
regular maintenance and
and booted with
components
require
occasional repair,
and
they must be assembled properly and carefully the boat
is
if
to be dry.
Watertight joints are our
first
order of business.
Boatowners today don't need even a passing
acquaintance with irons;
molded
oakum
hulls are
completely seamless, and
the fiberglass hull that leaks, no matter
rare
is
old.
Deck
The
dirty
boats with molded-in nonskid
how
leaks are, unfortunately, another matter. little
secret of fiberglass boats
is
that
most
more watertight than a colander. Wash-down water? A significant amount of all three finds its way below. are only slightly
drip
leaks don't just
on bunks, and
wood
wet the contents of
trickle across soles;
lockers,
they destroy
and delaminate
core, corrode chainplates,
bulkheads. Identifying and eliminating leaks
Those with planked decks in
essential. This
book
details the
most
effective tech-
It
instructs
you
in
Eventually, of course, a hull-and-deck-repair
book for fiberglass boats must come around
also
how to
locate pesky leaks.
Often
all
that
is
test
your work and
a fiberglass hull
is
gloss can be the easiest of repairs to fiberglass;
where we begin our exposition of this affect
a
An older fiberglass deck hairline cracks,
may have
is
likely
to be
webbed
it is
hulls.
with
even pocked with open voids, and
stress cracks radiating
5
shows you how to
hull repairs
from corners or
quick look
in
Chapter 7
in
Chapter
4.
of the materials
deck to perfection are
provided.
after
at
on
blis-
impact damage. A
common
repairmg will
rud-
have taken the
cannon.
When
boats were built of wood, a truly pro-
all
fessional repair required the
skills
of
someone with
years of experience. Not so with fiberglass. Pay
deck that
is
a
it
virtually
a try,
no
and you
will
discover
repair to a fiberglass hull or
motivated owner can't do as well
as quickly) as a pro.
by the necessity of
deck delamination and
der and keel problems, and you
that there
repairs are complicated
will find
— dealing with gouges, repairing
ways to
repair these blemishes. Step-by-step
repair
and reconstructing
attention and give
Deck
is
replace spongy core. Chapter 6 focuses
from beneath hardware. Fortunately there are easy
instructions for restoring the
You
answers to these questions and more
ters,
material.
decks more than
should you use
when epoxy? What
vinylester? Cloth, mat, or roving?
how to
wrong with
When
ready to take on more complicated repairs. Chapter
chalky surface or a few scratches. Restoring the
The ravages of time
providing clear and concise descriptions of the
involved and guided by clear illustrations, you are
portlight replace-
shows you how to
It
to
repairs requiring fiberglass lay-up, but not without first
Armed with an understanding
ment, hull-to-deck joints, and centerboard trunk repairs.
be more interested
overlay.
provides specific sealant recommendations for
various uses.
the included
the section detailing the care and repair of teak
polyester resin and
nique for sealing joints and bedding hardware, and it
will
various materials to be used.
is
will find
of
instructions for renewing those surfaces useful.
Spray? Rain?
Deck
Owners
providing effective nonskid surfaces.
caulking and firming
Frozen snot, indeed!
(if
not
ly
Q \ V -Vx^CVv.
!*ni
o
LEAKS
Leaks are insidious. A tiny leak, left unattended for months or years, can easily result in
dannage that
or take innumerable hours
will
if
cost thousands of dollars to have repaired,
you make the
repairs yourself.
There are the obvious things: ruined interior varnish below leaking ports,
mildewed upholstery from
trickles
from the hull-to-deck joint,
punky cabin
a
sole from "mysterious" rainwater intrusion.
As serious as these to the deck core,
age
is
are, they're small potatoes.
The biggest
and you may not see any evidence of a
from leaks
risk
leak until major
dam-
already done.
The decks of most fiberglass boats are made up of a plywood or sandwiched between two skins of fiberglass. saturation but
no
duction boats.) result
is
is
likely
If
less
(Closed-cell foam,
susceptible to delamination,
is
found
balsa core
more
resistant to
in relatively
few pro-
water penetrates the fiberglass skin and gets into the core, the
to be failure of the
bond between the core and the
core delamination weakens the deck. Delamination
is
skin(s).
accelerated
if
This
the boat
is
subjected to temperatures that cause the trapped water to freeze and expand.
The water entering like filling a jug.
a
cored deck cannot get back out; the flow
Balsa cores
become
saturated and mushy. Plywood soon
is
deck.
rots. In
cutting
prevented with four-bits' worth of caulk and an hour's worth of
become
one way,
away the fiberglass skin and replacing After you do this job once, knowing full well that it could have been
both cases, the only solution the core.
is
religious
about maintaining
a watertight seal
effort,
you
around any hole
in
will
the
—
CHOOSING A SEALANT You walk into a marine store and there they are, dozens of different cartridges and tubes standing on Geez,
how many
Three. That's
shelves, stacked in bins,
different kinds of it.
and hanging
in blister cards.
marine sealants can there be?
Three. Understand these three and you have the selection
process whipped.
POLYSULFIDE Polysulfide sealants;
is
Army
the Swiss
you can use
called Thiokol (a
for
it
best choice for bedding teak
marine
knife in
almost everything. Often
trademark for the polymer that
types of sealant, often taking a
is
reach
the main ingredient of all polysulfide sealants regardless of manufacturer), polysulfide
As a bedding
compound
ments associated with
stress
allows for
it
be sanded
after
it
Use polysulfide Polysulfide
bonds
compound
cures and
it
POLYURETHANE
since
causing
can
to harden
and
any
some
split.
attack both. or Delrin tings
Any
or PVC,
plastic fitting
— such as quality
— may be
safely
and polysulfide
made of epoxy,
plastic through-hull
bedded with
doesn't turn loose. Poly-
such a tenacious adhesive that
is
should be thought of as permanent;
you
will
want
if
will
nylon, fit-
its
there
to separate the
is
bond any
two
don't use polyurethane to seal them.
Use polyurethane anywhere you want a permathe best sealant for the hull-to-
nent joint. This
is
deck joint.
also a
fittings
It is
and
good choice
fortoerails
and
for through-hull
rubrails,
but not
some teak cleaners
on most
plastics
—
acrylic,
if
they
soften
Like polysulfide, polyurethane should not
to bed plastic deck fittings
ABS
urethane
it
are raw teak because
or polycarbonate
(including portlight frames); plastic marine fittings
are generally either
the bulldog of marine sealants
gets a grip,
parts later,
use polysulfide to bed plastic port-
it
it
is
likelihood that
takes paint well.
as well to plastic surfaces as to
lights, either acrylic (Plexiglas)
(Lexan). Don't use
is
for everything except plastic.
them
Specifically, don't
it
once
by
seal
other, but the solvents in the sealant attack plastics,
week or more to
cure.
Polyurethane
gripping tenaciously to both surfaces. Polysulfide also an excellent caulking
full
move-
and temperature
change, yet maintains the integrity of the
trim.
a syn-
is
thetic rubber with excellent adhesive characteristics.
and
rails
Polysulfides are the slowest curing of the three
it.
be used
polycarbonate, PVC, or
ABS.
The cure time
for
polyurethane
shorter than polysulfide, but
still
is
generally
may be up to a
week.
polysulfide.
The black caulking between the planks of a teak deck
is
polysulfide. For this application, a
two-part polysulfide gives the best
Because polysulfide adheres well to teak cial
8
(a
spe-
primer improves adhesion), and because
unaffected by harsh teak cleaners,
>- LEAKS
SILICONE
results.
it is
it is
also the
seem like the snake oil of the marine sealant trio. A bead of this modern miracle is too often expected to cure any and every leak. And it Silicone can
A POLYSULFIDE USE: All purpose deck hardware, through-hull sealant for
wood
trim, etc.
Caulking
SILICONE
bedding
USE: Gaskets. Portlight bedding.
fittings,
compound
Insulation for
Good flexibility and allows removal of bedded parts. May
teak decks. for easier
attack plastics
1
— not recommended for $
1
3
per
1
0-ounce
joint,
then tighten after
cure.
cartridge.
CLEANUP: Trim and
METHOD OF APPLICATION: Snug joint,
"roll" off
excess after cure.
then tighten after cure.
CLEANUP: Trim and
me-
0-ounce cartridge.
Snug $9 to
dissimilar
METHOD OF APPLICATION:
portlights.
COST RANGE:
between
Not for use below waterline. COST RANGE: $6 to $ 1 per
tals.
CURE TIME:
peel off excess
SHELF
1
to 7 days.
LIFE: 10 to 20 years.
after cure.
CURE TIME: SHELF
2 to 7 days.
LIFE: 2 to 5 years.
POLYURETHANE USE: A permanent sealant for through-hull fittings and hull-to-
deck joints. May attack plastics— not
recommended
COST RANGE: ounce
for portlights,
S7 to $1 5 per 10-
cartridge.
METHOD OF APPLICATION: Bead between parts to be assembled.
CLEANUP:
Mineral
before
spirits
cure.
CURE TIME: SHELF
does
2 to 7 days.
LIFE: 5 to 10 years.
— for about as long as
magic
elixir
salesman to
bead releases tube
full
worm.
its
grip,
wrist action,
not
lost
up
is
at least catch dinner.
a gasket material — period.
number
you
will find
it is
abilities as
If
tempo-
the best product for a
of sealing requirements.
It is
between components that must be
periodically dismantled
— beneath hatch
slides, for
example.
as a
as a dangling rubber
you think of silicone's adhesive rary at best,
ket material
— with a hook and the right
you can
Silicone sealant
used to take the
out of town. Then the
and what started out
of promise ends
All is
it
slip
the only one
Silicone retains
resilience for
its
decades and
is
unaffected by most chemicals, but
it
should not be
used below the waterline. Because
it
depends upon
mechanical compression to maintain
cone
is
its
seal,
sili-
not the best choice for sealing hardware on
a cored deck.
Exposed
but repels paint
like
silicone
is
a
magnet
for dirt
an opposite pole, so never fillet
of the marine sealant trio than can be safely used to
with silicone, and don't use this sealant on any sur-
bed
face you plan to paint.
plastic.
It is
similar metals
an excellent insulator between
— use
it
when mounting
hardware to an aluminum
spar.
It is
dis-
stainless
the perfect gas-
Silicone sealants typically set in a
and usually reach
full
cure
in less
few minutes
than 24 hours.
CHOOSING A SEALANT
A USEFUL HYBRID THERE IS A BIG ADVANTAGE TO USING A SEALANT with good adhesive properties. An adhesive sealant maintains
its
seal
even when stresses
pull or pry
the
ness of silicone. Although silicone has amazing elasticity, its
lack of adhesion
bedded components apart, the sealant stretching and compressing lii- LEAKS
is
guaranteed to return greater
relative
Remove the fitting. This
is
usually the hardest part of
the job, either because access to the fasteners ficult to
gain or because the bolts are frozen
is
dif-
— or
both. Access sometimes requires removing headlin-
by simply
ers or cabinetry, but don't try to avoid this
running a bead of sealant around the
do
you
that, eventually
ting, only this
time
In
will
fitting.
If
you
be removing the
still
fit-
preparation for major deck
repair.
For access to the fasteners securing
wooden
components, the bungs hiding the bolt heads
will
have to be removed. This can be accomplished by drilling a small
hole
in
the center of the bung and
threading a screw into
when
it;
the point of the
screw finds the screw head below the bung, continuing to turn the screwdriver Extracting
the bung hole. with a
will
lift
the bung.
way can sometimes damage A safer method is to drill the bung
bungs
bit slightly
this
smaller than the diameter of the
bung, then carefully remove the remaining ring of material with a small chisel. If
the
fitting
was
installed with polyurethane,
removing the fasteners may have to pry the fitting loose
the deck and the cially
metal
is
fitting.
fittings) or
likely
little
to result
Heating the
effect. in
Trying
damage
to
fitting (espe-
the deck can coax the
polyurethane to release
its
grip.
HEADUNERS HEADLINERS ARE AS VARIED AS BOATS. If the headliner is fiberglass, you likely cannot remove it (without removing the deck). Occasionally manufacturers bolt
hardware to the deck before
the headliner. You liner
will
installing
have to cut or
drill
it
over
the head-
beneath the fasteners to gain access.
liner
and
pulling the liner loose at that end.
staples out with a flat screwdriver at the
Work the
seams
until
you
uncover the desired area. Be sure you use Monel staples
when you
replace the
liner.
For
Canvaswork and Sail Repair in
more on
headliners, see
this series.
Reinstall
the hardware with longer bolts through spacers and
deck
a backing plate that covers the cutout.
When
the headliner
is
made up of panels,
it is
usually captured by trim pieces screwed in place.
may also attach with Velcro. Sewn headliners are typically stapled to wooden strips across the overhead. You can't see the staples Panels
because they are through the excess material onthe back side at the seams. You gain access by removing the trim piece at the forward or aft
end of the
spacers
backing
headliner
V o
plate
B!a-j)rjnt*^*^wt'7j«
REBEDDING DECK HARDWARE
>-
11
Clean off the old bedding. Every trace of the old sealant
must be removed. Use
or a wire brush as required,
and the
fitting
a blade, sandpaper,
and clean both the deck
with acetone.
Mask adjacent
areas. Cleaning
up the squeeze-
out with solvent takes twice as long as masking
and
is
trace
ten times
around
it
more messy.
Dry-fit
with a pencil. This
is
strengthen the mounting location
"Deck
Repairs").
pencil line
Mask the deck
the part and
the time to
if
required (see
Vs inch outside the
and mask the edge of the
fitting.
Coat both surfaces with sealant. Cut the
tube or cartridge
at a 45° angle
tip of
— close to the
the
tip for
a thin bead, farther back for a thicker bead. (Cart-
ridges have an inner seal
with an ice
pick.)
you
will
have to puncture
Apply the sealant with a forward
motion, pushing the bead
in
front of the nozzle.
Coat both surfaces to make sure there
any gaps
in
will
not be
the bond; use a putty knife to spread the
sealant evenly, like buttering bread. Before inserting
the mounting bolts
— not screws — run
sealant around each just
a ring of
below the head. NEVER
apply sealant around the fasteners on the underside of the deck;
if
the seal with the outer skin breaks,
you want the water to pass into the cabin where will
12
5^ LEAKS
be noticed.
it
—
"
Assemble the parts and "snug" the fasteners enough to squeeze sealant out
all
the
Wait
until
silicone,
way around.
then
the sealant partially cures
24 hours
fully
for polysulfide or
— 30 nninutes for
polyurethane
tighten the bolts by turning the nuts only
to prevent breaking the seal around the shank of
the bolt.
If
the
fitting
draw them one
is
attached with screws, with-
at a time, run a
bead of sealant
around the shank beneath the head, turn,
7-^^::::r-
y^~^ ^**!>*^
"^s-i^
x^
then drive them
^
f^
C^^
^'7
/\^_i^
in
Trim away the excess squeeze-out
by running the
fitting,
a razor blade
around
then peeling away the
around the edge; dirt,
a
fillet
silicone attracts
polyurethane yellows, and
polysulfide
^M
each
home evenly.
masking tape. Never leave
/^ih ^ ^/^ ?
8
all
reinstall
so you
weakens
want the
sealant visible
in
least
of
fitting. Install
new bungs, matching and
amount
— only the thin
edge beneath the grain
the sun,
setting
color
and
them with
varnish.
REBEDDING DECK HARDWARE
>
13
—
PREPARING A CORED DECK
FOR NEW HARDWARE marine good Asnever depend on them the core of a deck or hole
in
Anytime you
drill
or cut a
large
A
procedure before
do
fitting,
chucked
nail
power
into a
cut oversize.
Vacuum cavity;
you
Redrill
the cavity with
way
a
is
remove
as a
the cured epoxy.
two-
Sand and clean the
First seal
area that
duct tape, then pour
under the
Now you
catalyzed epoxy into
the cavity
When
is full,
ture the tape
to
let
the epoxy run out back into
your glue container. Filling the cavity with unthick-
ened epoxy allows the epoxy to better penetrate the edge of the core. Retape the bottom hole. there are several mounting holes, drain in turn until
all
fill
If
each and
have been treated and
all
resealed.
The second step is to thicken the epoxy (the same mix you have already poured through the holes) with colloidal
tency.
Now
fill
silica
each cavity
allow the epoxy to cure
>- LEAKS
will
be
fitting.
are ready
bed the new
hardware as
punc-
and
bottom holes
filler.
the mount-
the bottom hole with
the top hole.
14
whatever
ing holes through
epoxy. The most secure
from the
can't
will act
drill.
the pulver-
ized core
step process.
core
this easily with a
bent
doesn't need to be
Fill
to a
mayonnaise consis-
level
fully.
with the deck and
you are rebed-
time, be certain that
reinstalling the fitting.
the hole. You can
example
first
If
the core has been properly sealed, or follow this
within V2 inch of
hole— for a
through-hull
ding old hardware for the
Remove all the
fastener
holes oversize.
for
hull.
to keep water out of
the deck, seal the exposed core with epoxy
Drill all
1
before mounting any hardware.
sealants are, you should
as
detailed
in
the
previous section.
SEALING CHAINPLATES When water culprit
is
finds
way below, very often the
a leaking chainplate. Chainplates'
propensity to leak
understandable; they are bed-
is
ded under moderate sail
its
fixed stress, but
once under
usually not to the deck;
enough not to have chainplate openings located a cored section of the
yours).
It is
the
yanked and eased while the leeward chainplates
sealant lower
are virtually released. This tries the grip of any
before
They are also stressed
by poor sheet
leads,
in unfair
rig
deck (but you should check
that
is
at risk.
directions
shroud encounters with the
on the chainplate stops the leak
enters the cabin. This results
it
ure.
shroud or stay runs
down
the wire and across the
As annoying and potentially damaging as a leak
plates that
is,
the larger
is
often from chain-
appear to be watertight. The danger
Remove the trim
1
risk
plate ifthere
one.
is
lem
— short of catastrophic
is
Pull
bolts
chainplate.
necessary to
you
plate
shroud or stay by
check
if
corrosion.
doesn't
the
It Is
only
easily,
If it
come out
pass a long,
only one shroud at a
round screwdriver
time. Before releas-
shaft
ing a stay always set
pinhole and sup-
up
port the
end on
wooden
block
port the mast.
to pull the
for signs of
buckle and pulling
a halyard to sup-
is
you want to
It
slackening the turn-
Disconnect
—
prob-
remove the chain-
disconnect the
pin.
failure
this
below deck
way, but rebedding if
fail-
the mounting
taped up out of the
easier
chainplate
you rebed them.
and extract the
much
in
hidden by the deck
it. If you have never fully examined your chainplates, or if it has been a few years, you are strongly urged to pull them before
This can usually be
is
is
will,
chainplate and examine
turnbuckle directly to the chainplate.
into the cabin
Because the erosion
and/or sealant, the only way to detect
and spray gathered by the attached
the chain-
sion resistance of stainless steel, this situation
over time, almost certainly result
body support coming aboard. When the seal
in
plate sitting in a ring of water. Despite the corro-
dock, and by the use of shrouds for
rain
the seal at the
If
or as handholds for fails,
in
deck breaks, water penetrates, but additional
the windward chainplates are alternately
sealant.
most manufacturers know
while
through the
lifting
a
on the
handle.
SEALING CHAINPLATES
»
15
Dig
all
oftheoldcauikfromthehole. Apieceof
hacksaw blade can be
useful for this, but
be careful
not to enlarge the hole through the deck; the tighter the chainplate
fits,
the less
longer your bedding job trim plate,
it
move, and the
will
will last.
Clean the deck,
and chainplate of old bedding. Examine the caulk area carefully; any
the chainplate
in
ting, cracks, or
brown
ment. Wipe
pit-
discoloration indicate replace-
down the deck, trim
plate, chainplate,
and the inside of the hole with acetone.
Reinstall the chainplate
trim plate
and trace around
above the trim plate.
the
is little
install its fasteners.
to be gained by two-stage tight-
ening, so tighten these screws
squeeze out of the
16
>- LEAKS
slot
and
all
fully.
Sealant should
around the
line,
the chainplate
chainplate. Use the
flat
of a
and the bottom of the trim
plate
with sealant.
Because the trim plate screws are generally quite small, there
with a pencil. Mask
between the chainplate and the deck
Butter the deck
\\
and
the
flexible putty knife to force sealant into the crack.
\\
position
Dry-fit
and the top surface of the trim
way around the
>
- LEAKS
and the
through-hull threads and flange with polyurethane
all
and
tighten;
around the outside
away the excess and use some
the heads of the flange
bolts.
of
it
to
PRESSURIZING
TO FIND LEAKS
Some leaks into the cabin are obvious, but most aren't.
travel
Water may leak through the deck, then
along the top of a headliner
feet or
1
more
before finding an exit and dripping out. The traditional
way of finding
Shut
all
leaks
is
seacocks and close
moving the hose incrementally "up" the deck the drip appears. This method often
method
that requires a bit
more
fails.
effort,
until
Here
but
is
a
will
it
locate every leak.
to flood the deck,
all
hatches.
1
Use duct tape to to be airtight,
hawsepipes,
seal
i.e.,
all
openings you don't expect
ventilators, cockpit hatches,
etc. Seal
plastic sheeting (a
the
companionway with
garbage bag
will
be adequate)
edge-taped over the hatch and the dropboards.
Insert the nozzle of a small electric leaf
blower into
an open ventilator or deck plate and seal tape.
it
with
A shop-vac with the hose on the "blow"
side
will also serve.
With the blower running (give pressurize
all
water over
it
five nninutes to
the internal spaces), sponge soapy
ports, hatches, and hardware. Anywhere you see bubbles, you have a deck
After
all
you rebed the
identified fitting,
leak.
you can
pressure-test again to confirm that the leak
is
resolved, but don't leave the tape in place for
than a few hours
have great
— never overnight — or you
difficulty
removing
more
will
it.
FINDING LEAKS
>-
29
30
RESTORING THE GLOSS Production fiberglass
boats are built by laying
nnultiple laminates into a
The bright
interior of
the mold
and coated with
then the
first layer,
polished mirror-
to get a reasonably
is
agent (wax);
a releasing
is
sprayed onto
layer of fiberglass
initial
is
added
the builder achieves
until
due
This
is
opposite of the
are manufactured, tion
is
son
to spray
it's
way most other products
where the
on the
finish
last
produc-
in
— presumably the rea-
called the finish. Gelcoat
the
is
Gelcoat also differs from paint tant ways.
step
in
is
mechanical
start.
other impor-
— that Passion
Crimson enamel on your old Roadmaster ing
on
(or not)
hang-
by gripping microscopic scratches
put there by sanding or chemically etching the metal.
Between gelcoat and the underlying
nates, the
bond
is
chemical; the resin saturating the
layer of glass material
first
This
a single
— not unlike pouring warm gelatin over cold.
is
called chemical cross-linking,
because gelcoat
resin
and
and the polyester
it
occurs
resin
used
to saturate the layers of fiberglass material are the
same basic product. Gelcoat mented polyester resin.
is
essentially pig-
Good
is
paints are self-leveling
much
—
like
water
— drying
to a smooth, glossy finish, but gelcoat resin
new fiberglass
boats
is
thicker than a paint finish. For
finish (Awlgrip)
to 0.002 inch) thick. layer of a boat just mils, give or
to 2 mils (0.001
popped from the mold In
is
is
20
other words, the
typically thinner
page of this book, while
a single will
is 1 .5
The thickness of the gelcoat
take 3 or 4 mils.
than
a layer of gelcoat
normally be about 10 pages thick.
A well-applied
gelcoat
(like
everything
else,
there are quality differences between manufacturers) will
generally
last
care. Protected with
compounded its
10 years with minimal or no
an annual coat of wax and
in later years,
gelcoat can maintain
gloss for 20 years or more. is
due
primarily to
its
The longevity of gel-
thickness.
When
the sur-
face dulls and chalks, the "dead" layer can be
abraded
off
and the fresh surface underneath
pol-
ished to restore the gloss.
Thickness can also be the enemy.
If
the builder
— often done with the best intentions on early fiberglass boats — applies the gelcoat too thickly
it
eventually cracks
Gelcoat resin has poor flow characteristics.
but the "wet-
example, the dry film thickness (DFT) of a typical
coat
combines with the
exposed surface of the gelcoat to form
mass
lami-
finish,
entirely to the highly polished interior surface
Gelcoat
Fruit is
smooth
paint on a painted surface
The bond between paint and the under-
lying surface
taking on the texture of
can be thinned and sprayed
of the mold.
polyurethane
the desired thickness.
It
look" gloss characteristic of
applied to the "back" side of the gelcoat, and additional layers are
like plaster,
boat-shaped mold.
called gelcoat,
the mold surface. The
behaves more
the application tool.
like
dried
mud. A
faulty resin for-
mulation can also cause cracking and crazing. Except for color matching, gelcoat repairs are easy and straightforward.
31
BUFFING The most common surface malady of fiberglass boats
is
a dull finish. This
is
brought on almost entirely by exposure and can be delayed significantly by regularly
waxing the gelcoat.
perhaps even chalky, waxing
When will
unprotected gelcoat becomes
no longer restore the
gloss.
dull
and porous,
The damaged surface
must be removed by buffing the gelcoat with rubbing compound.
START WITH A CLEAN SURFACE
Wash. Scrub the surface thoroughly with
1
of
1
a solution
cup of detergent per gallon of water; choose
liquid detergent,
even more phate
such as Wisk. To make the solution
effective, fortify
(TSP), available at
surface
a
it
with trisodium phos-
any hardware
store.
shows any signs of mildew, add
a
If
the
cup of
Degrease. Soap solutions
surface,
sweep
in
MEK
suspension longer.) Protect
your hands with rubber gloves and turn the rag often,
available.
dry.
or
with an MEK-soaked rag. (Acetone
holds contaminants
oughly and
it
it
can also be used, but the slower-evaporating
chlorine bleach to the mix. Rinse the surface thorlet
may fail to remove oil
grease from the porous gelcoat. To degrease the
changing
it
when
a clean area
Dewax. Rubbing compound works
no longer
is
like
very fine
sandpaper, and wax on the surface can cause
uneven cone on
cutting. In addition, it
if
the surface has
(nine boats out often do), the
sili-
compound
drags the silicone into the bottom of microscopic scratches,
which
paint the hull.
will
cause you grief
Wipe the
hull
if
you ever
with rags soaked
toluene or a proprietary dewax solvent. Wipe single direction, usually diagonally
toward the waterline.
32
>-
RESTORING THE GLOSS
in
in a
downward
CHOOSE THE RIGHT COMPOUND Gelcoat
AUTDMDTIVE
much
is
compound. coat
is
in
softer than paint
Select a
and requires
compound formulated
a gentler
rubbing
for fiberglass.
If
the gel-
especially bad shape, the heavier abrasion of an automotive
compound can
provide faster surface removal, but
it
must be used
with caution to avoid cutting through.
FIBERGLASS „,,^n RUBBING CDMPDLiNU
•^
PLUG
IN
Rubbing compound can be buffed out by hand the area
is
small, but hand-buffing
an entire boat
not recommended. An orbital polisher
cheaper than an
artificial
a buffing disk into
your
through the gelcoat, or ning
it
if
is
is
far
elbow. Don't try chucking
electric you'll
eat right
drill; it will
burn up the
drill
run-
slow.
THE RIGHT PRESSURE How much
of the surface the
relates directly to
Since you always
how much
You
much
that
will
pressure you apply.
want to remove
as necessary, never use any required.
compound removes as
the process
is
how
it
hull
a small repair
with the aid of a machine,
the same. Working a small area at a
time, apply the
compound
to the surface by hand,
with a circular motion. Use heavier
initially,
then progressively reduce the
pressure until the surface If
is
is.
by hand or an entire
pressure
gelcoat
have to experiment with
Whether you are compounding
then buff
little
more pressure than
becomes
glassy.
the gelcoat shows swirl marks, buff them out
with a very fine finishing
compound.
BUFFING
>-
33
SANDING Sometimes the dead
layer of old gelcoat
compound becomes by sanding the surface through the gelcoat, restore
its
interminable.
first.
In
so deep that removing
is
with rubbing
that case, the process can be accelerated
This only works
if
the gelcoat
too thin to restore and you
it is
it
will
is
thick;
if
you sand
have to paint the surface to
gloss.
HIGH SPEED AND HIGH RISK Don't
let
the sander
run over any high spots, ridges, or
corners, or
It
will
cut
through the gelcoat regardless of
how thick it
is.
Change paper
when
the
amount of sanding dust
diminishes.
/^S^'-'^V
'•.-..
M> / The
1
220-grit
way to sand gelcoat is by hand, but you the time required to remove the dead sur-
safest
can slash
face layer by using a
power sander. You
V4-sheet finishing sander
Load
it
with
brown). spot to
It is
1
a
make
20-grit
good
— called
working
at
a
aluminum-oxide paper
sure your gelcoat
about 200
in
is
thick
^
maintain contact. This
much first
to
mind that the sander
orbits per second, so
seconds. Apply only as
keep a
is
Hi
it
few
pressure as needed to
pass removes most of
the material;
if
good
from the remaining steps are
>-
a
(it's
enough
moving and don't sand any area more than
results
need
will
palm sander.
idea to start in an inconspicuous
take this treatment. Keep
34
='i^^t
the gelcoat doesn't get transparent,
RESTORING THE GLOSS
likely.
When you have
run the sander over the entire area,
change to 220-grit paper and do
it
again.
WET SAND
Remove the
1
scratch marks
power sanding
left
behind by wet sanding the surface with 400-grit wet-or-dry (silicone carbide) sandpaper.
Hand sand
To ensure
a
uniform surface, backing sandpaper
with a rubber or idea,
but
—
when you
wooden
the
grit
is
block
is
usually a
very fine
same
good
— 320 or and perhaps
with a circular motion, keeping a trickle of water
higher
running on the sanding area.
better control from finger-backed sanding. Fold the
will
get the
results
sandpaper as shown to keep the paper from sanding
itself
and to provide three
fresh faces
from each
piece of paper.
J
Wear
cloth
garden gloves
— the
kind with the
hard dots
— to
save the tips of your fingers.
Make
X
\
I
a final pass with 600-grit wet-or-dry
paper
and the surface should be ready to buff to
a like-
new gloss.
WHAT? THE HIGH SPEEDS OF PALM SANDERS— about 14,000 rpm— can result damaging shriek. Earplugs are available from any drugstore for about
in
an ear-
buy and use them. Not only will they save your hearing, but by eliminating the fatigue that accompanies such an assault on the senses, they actually make this a buck;
a pair
job
much
easier.
SANDING
>
35
SCRATCH REPAIR Scratches
are less visible
ferent color base.
good
If
some
the surrounding gelcoat
condition, always
though the gelcoat application may
on gelcoat than on
paint since they don't cut through to
make
is
dif-
in
blend imperceptibly with the
damage
surface
try to repair a
You
too thin to
is
and
if
paste. Paste
the
you want
thickened to a
permanent
or screwdriver
chamfer on both
matching the
selection of pigments
down
can be purchased for
sides.
Even prohave diffi-
color.
is
one of the few
for conditioning yourself to
be
happy with a self-assessment of "not bad." You can purchase gelcoat as unpigmented resin, in a kit
with a half-dozen different colors of
inorganic pigments, or
most popular
in "factory"
colors won't
colors for the
boats. Because pigments fade,
boat has seen a few years
match
in
if
a
the sun, even factory
exactly.
For small repairs to a white boat, a
kit
with
pigments should serve; getting close is much easier with white, and once the repair is buffed out to a gloss, smalt shading differences will be unnoticeable.
36
containing
amount of gel-
less
RESTORING THE GLOSS
than $20.
For colored hulls
repairs daily
culty getting a perfect match. This
may call
what
ener along with a
a
it.
and
places that
is
coat paste and hard-
filling
THE HARDEST PART OF A REPAIR TO THE SURFACE is
thicker
for scratch
repair. Kits
a small
WHAT COLOR IS WHITE?
do gelcoat
in a
putty form called
the
fill
and
rather than
draw the corner of a scraper
fessionals that
gelcoat
bridges the scratch
To get
of a fiberglass boat
will find
resin
with
it
paste, the paste
a
damage the
painting over
resin
and put
For
available as both a
scratch,
it
hull.
scratch by simply
is
the scratch to open
the
GELCOAT CHOICES
gelcoat. Gelcoat resin
repair,
be
underlying laminates, see "Hull Repairs."
OPENING A SCRATCH FOR REPAIR Never
rest of
dealing with deeper gouges that also
Even
repairs with gelcoat rather than paint.
it
initially
can be sanded smooth and polished to
rough,
larger repairs,
getting an adequate
match cult.
It
is
more diffi-
essentially
requires tinting an
ounce of gelcoat with one drop of pigment at a time and touching the resulting mix to the hull until you get a match. Keep track of the number of drops of each tint per ounce to reach the right color. Guys, get your wives or girlfriends to help you with this part; men are eight times more likely to have defective color vision a minus that becomes a plus if your repair
—
is
slightly off (you
won't notice).
For additional assistance
see Sailboat Refinishing
in
matching
in this series.
colors,
CATALYZING The hardener for gelcoat
is
the
same
as for
any polyester
ketone peroxide, or MEKP. Gelcoat resin usually requires
resin 1
— methyl ethyl
to 2 percent of hard-
ener by volume (follow the manufacturer's instructions). As a general
drops of hardener
will
catalyze
1
ounce of
resin at
kick (start to harden) in less than 30 minutes.
probably
\dea\.
Always
err
the hardener thoroughly; repair will
on the side of too if
you
fail
1
percent.
Hardening
little
in
rule,
four
The mix shouldn't
about two hours
hardener. Also be certain to
is
stir in
to catalyze every bit of the resin, parts of the
be undercured.
SPREADING GELCOAT PASTE
Apply gelcoat paste
like
any other putty;
a plastic
spreader works best. Let the putty bulge a
behind the spreader; polyester as
it
cures,
and you're going to sand the patch any-
way. Just don't extra
Original gelcoat
1
is
bond between
is
strictly
it
bulge too
much
or you'll
make
bond
mechanical
applies
a long-cured hull
and an application of fresh gelcoat over scratch
let
for yourself.
chemically bonded to the under-
lying laminates, but this molecular
only to lay-up; the
work
little
resin shrinks slightly
—just
a ding or
like paint.
Wiping
the scratch with styrene just prior to coating can partially reactivate
some chemical ter this step
is
the old gelcoat and result
in
crosslinking, but as a practical mat-
usually omitted.
Scrape up any excess beyond the patch area.
SCRATCH REPAIR >
37
I
COVERING THE REPAIR
Gelcoat
will
not
fully
cure
in air.
remain smooth and the gelcoat
Large repairs require a
will
not adhere to
it.
coating of polyvinyl alcohol (PVA) to seal the surface
Tape one edge of the
(see "Laminate Repair"), but to seal a scratch repair,
the repair, then smooth the plastic onto the gelcoat and
cover
it
with a sheet of
plastic.
A
section of kitchen "zip-
per" bag works especially well because
it
tape
down
plastic to
the remaining sides.
tends to
SANDING AND POLISHING GELCOAT REPAIRS After
24 hours, peel away the
plastic.
The annount of sanding required
on how smoothly you applied the gelcoat.
For a scratch repair, a 5-inch length of
1
1
x 2
makes
convenient sanding block. Wrap the block with or
1
fine
50-grit paper,
1
and use the narrow side to con-
your sanding to the
new
strokes, taking care that the
gelcoat. Use short
paper
is
sanding only
the patch and not the surrounding surface. Never
do
this initial
sanding without a block backing the
paper.
38
RESTORING THE GLOSS
a
20-
will
depend
the surface just beyond
When
the
new gelcoat
is
flush,
put 220-grit wet-or-
dry paper on your block and wet sand the repair, feathering
it
into the old gelcoat until
you can
Switch to 400-grit wet-or-dry, abandoning the block,
and wet sand the surface appearance. Follow
until
it
has a uniform
with 600-grit wet-or dry.
this
detect no ridge with your fingertips.
Dry the area and use rubbing gelcoat a high gloss.
On
compound
small repairs,
to give the
you can buff
the gelcoat up to a gloss by hand. Give the repair area a fresh coat of wax.
If
sonably good, the repair
your color match
will
be
virtually
is
rea-
unde-
tectable.
SCRATCH REPAIR
>
39
40
DECK REPAIRS
A
fiberglass boat
molded
in
Most of the furniture and machinery before the deck goes on
If
you
good
life
stay off the rocks
—
two
like filling a
and don't smash
It is
is
born to a
life
assaulted by
of abuse.
It
rain, pollution,
sits
and the deck.
open
hull
box before putting on the
lid.
into the dock, the hull has a pretty
out
and
sections: the hull
installed inside the
is
— coddled by the water and always half
other hand, desert.
typically
is
in
foot.
in
the shade. The deck, on the
the sun It is
like a
piece of Nevada
eviscerated by openings,
pierced by hardware, pried by cleat and stanchion.
You might think that
to stand
up to such treatment, decks are
the hull they cover. You'd be wrong. Weight carried low
built as
—
as strongly
in a
boat has
lit-
make the hull as thick as he feels like but weight carried high reduces stability. A deck must first be light; strength is defined by "strong enough." As a result, the need for deck repairs is far more
tle
detrimental impact
common
^^
Deck
than the need for repairs to the
is
a
hull.
be more complicated (but not necessarily "harder").
repairs can also
While the surface of a
deck
a builder can
hull
is
flat
or uniformly curved
and
landscape of corners, angles, curvatures, and textures.
extends under deck-mounted hardware. Backside access
molded
relatively featureless, a
headliner.
And
Damage
may be
often
inhibited by a
to provide stiffness without weight, deck construction
generally involves a core. In this
chapter
constraint;
we will
confine repairs to surface damage. This
most deck problems are
is
hardly a
limited to the deck's top surface.
41
—
STRESS CRACKS RECOGNIZING STRESS CRACKS Stress cracks are easy to identify
by
their shape. Typically the cracks run
You will see parallel cracks in molded corners, such as around the perimeter of the cockpit sole or where the deck intersects the cabin sides. These suggest weakness in the corner. Parallel cracks also show up on either side of bulkheads or other stiffening components attached to the inside surface of the hull or deck. The concentration of flexing stresses at such "hard spots" causes the gelcoat, and sometimes the underlying laminate, to crack. parallel or fan
Starburst cracks are also caused by flexing, but
case the
movement
falling against lifelines or
in this
by pulling oneself aboard with
the top of the stanchion, which
up around the socket mounting
3^
in starburst pattern.
centers at a point rather than along
an edge. The most common starburst cracking extends from beneath stanchion mounts, brought about by
42
out
DECK REPAIRS
literally levers
holes.
the deck
Another cause of starburst cracking is point impact, such as dropping an anchor or a heavy winch handle on deck. (Exterior like
impact may instead
the pattern of a target.)
result in concentric cracks
ELIMINATING THE CAUSE Backing plates. Starburst cracking can usually be stopped by
generous backing plates on the underside of the deck beneath the offending hardinstalling
ware to spread the
load.
Wooden
plates are the
easiest to fabricate, but stainless steel or bronze
are better because of their resistance to crushing. Bevel
the edges of the backing plate to
avoid causing a hard spot. Polished stainless steel plates with
threaded holes make for an
attractive installation.
Hard spots.
Stiffening.
Hard spots are more
common on the
hull
than the deck,
and usually appear where bulkheads attach. Stress cracks around hard spots are likely to return unless you eliminate the hard spot. This typically involves detaching the offending
fixture,
then reattaching
the work required
bulkhead
is
around cockpit
soles,
can
be prevented by stiffening the area with additional laminates. Laminating instructions are provided in "Laminate
some material from the edge, mounted on a foam spacer. Realistically,
strength, which translates into laminate thickness; use
may exceed
fiberglass
shaving it
Stress cracks related to general laminate weakness, such
as those that too often appear
the benefit, but anytime a
detached or a new bulkhead
is
installed,
Repair." In this case
mat
you are trying to add
stiffness,
not
to quickly build additional thickness.
it
should always be mounted with a foam spacer.
STRESS CRACKS >-
43
REPAIRING THE CRACKS Cracks layer,
in
the deck typically affect only the gelcoat
and perhaps the
first
layer of
mat beneath
the gelcoat. Repairs are identical to scratch repair detailed
in
may need
the previous chapter, except that you to
remove deck hardware to get
full
access to the damage. Occasionally flexing has
Gain access to the entire length of the crack.
been so severe that
woven
fabric of the laminate.
the strength of the laminate
with gelcoat paste.
'^l
44
DECK REPAIRS
extend into the
When
is
this
is
the case,
compromised, and
the area must be ground out and relaminated to restore
it.
repair are
Detailed instructions for this type of
found
in "Hull
Repairs."
Open the
crack with the corner of a cabinet scraper.
Sand and
buff.
1
Fill it
stress cracks
VOIDS Voids are thankfully rare in the flat expanses of
common
in
when
first
the
hull lay-up,
but
all
too
fiberglass decks. Voids occur layer of cloth
is
not com-
pressed against the gelcoat (or
subsequent laminate
is
when
a
not compressed
against the previous one). They are often as
much
a
consequence of design
as of work-
manship. While crisp angles and corners look
stylish,
they are more
may
mold
difficult to
with glass fabric. The fabric resists being forced into a tight corner and after saturation
may take
a
more
from the gelcoated mold. The void
—
result
is
a
pocket of air beneath the thin
a
gelcoat, perhaps "bird caged" with a
random
strands of glass.
pressure like
away
natural shape, pulling
is
The
first
few
time
applied, the gelcoat breaks
away
an eggshell, revealing the crater
beneath.
Deck voids are a cosmetic problem and
Break away the cracked gelcoat to
easily repaired.
Use
a rotary
grinding point chucked
in
your
drill
to
grind the interior surface of the cavity. Chamfer the
gelcoat
all
fully
expose the void.
1
Clean the cavity with acetone. For a better bond,
wipe the cavity with styrene.
around the void.
VOIDS
>-
45
Fill
the cavity to the bottom of
the gelcoat with a putty
made
and
from polyester
resin
chopped
Be sure you use
glass.
laminating resin.
resin,
Epoxy
is
not finishing
not recom-
mended because you
are going
to finish the repair with a layer of gelcoat,
and gelcoat does
not adhere as well to epoxy as to polyester.
When
the patch hardens,
fill
the remaining depres-
sion with gelcoat, overfilling slightly. Roll a piece of plastic into
the repair and seal the edges with tape.
When the gelcoat cures, sand
it
flush
with the surrounding surface and buff it
with rubbing
the gloss.
46
>-
DECK REPAIRS
compound
to restore
CRAZING (ALLIGATORING) Crazing, sometimes called alligatoring, is a random pattern of cracks that, at its worst, can cover the entire surface of a fiberglass boat
deck and flexing
hull.
There are two primary causes:
and excessively thick gelcoat.
the culprit, the crazing
will
to be successful, stiffening
deck
in
be
If
flexing
is
localized. For a repair
must be added to the
the area where the crazing has occurred.
Fortunately the is
— both
more common cause
of crazing
gelcoat thickness (or occasionally gelcoat
formulation). As the hull heats
and
expands and contracts. A thin
layer of gelcoat
cools,
accommodates these changes, but not reinforced
like
it
thick gelcoat,
the underlying laminates, tends
to crack. In this case, the crazing extensive. That's the
is
likely
to be
bad news; the good news
is
that the repair doesn't require any structural alterations.
mi
LOCALIZED CRAZING
Stiffen
1
the crazed area. See "Core Problems" for
alternatives
and step-by-step
instructions.
CRAZING
5>
47
Trace each crack with the corner of a cabinet scraper, or
if
the pattern
is
too
fine,
with a 36-grit sanding disk. Stop
grind the area
when
the disk
begins to break through the gelcoat; don't grind
al
the gelcoat away.
Paint the cracks or
ground area with color-matched
gelcoat paste. Seal the surface to cure.
48
>-
DECK REPAIRS
let
the gelcoat
Fair
the
a gloss.
new
gelcoat by block-sanding, then buff to
WIDESPREAD CRAZING Sanding and polishing surface-applied gelcoat is
worthwhile
when
relatively small
good
the
and the
condition, but
original gelcoat
is
new
gelcoat area
the gelcoat
rest of
when
is is
in
the majority of the
damaged, the labor
intensive
nature of gelcoat application suggests a different
approach. The best alternative entire
deck with
Remove
1
ble.
as
a two-part
is
painting the
polyurethane paint.
much deck hardware and
The quality of your
trim as possi-
refinishing job
is
directly
—
how much hardware you remove how unobstructed the deck is when you apply the paint. related to
i
Clean, degrease,
and dewax
all
the
smooth surfaces of the deck. (Nonskid surfaces are restored
in a
Sand the gelcoat thoroughly with paper and wipe
it
1
20-grit sand-
dust-free with solvent.
separate
process.)
CRAZING >
49
Mask nonskid
surfaces
elected not to remove.
and any hardware you have
Paint the
sanded gelcoat with
a high-build
primer. Apply the primer with a
coats are generally necessary to porosity;
foam fill
all
epoxy
roller.
Two
crazing and
machine sand each coat with
1
20-grit
paper.
Paint the primed surfaces with
two coats of two-part
polyurethane, following the manufacturer's instructions for rolling and/or brushing the paint. For
plete instructions
on repainting decks
other boat surfaces
book
50
>-
DECK REPAIRS
series.
— and
— see Sailboat Refinishing
com-
all
in this
RENEWING NONSKID you paint the smooth surfaces of the deck, you
will
probably want to
refin-
If ish
the nonskid surfaces as well. Painting nonskid surfaces tends to reduce
their effectiveness.
Always
refinish
You can
by adding
grit to
the paint.
the textured sections of the deck after the smooth portion.
There are two reasons for a
easily offset this
this order. First,
the nonskid surface
darker color than the smooth surfaces, and
with a darker one than the other
done on the textured
surface,
it
it is
easier to cover a lighter color
way around. Second,
will
almost always
is
if
the
be hard to get a sharp
masking
final
line
is
between the
two. Prepare textured surfaces for refinishing before painting the other parts of the deck.
ENCAPSULATED GRIT Scrub the nonskid
1
thoroughly with a stiff
brush, then use
terry cloth
— sec-
tions of old bath
towels
— to dewax
the surface. The
rough surface of the terry cloth penetrates the craggy
nonskid.
You
can't sand the bot-
tom
surfaces of the non-
skid,
but abrade
it
with
coarse bronze wool, using short, quick strokes. Fortunately
most of the
new
on the
stress
paint will be
on the
top surface, which you can sand with 120-grit paper. Flood the surface
and brush-scrub then
let
it
it
again,
dry.
RENEWING NONSKID
>-
51
— After the
smooth
surfaces are
painted and dry, mask them at the mold line of the nonskid.
Mix a nonskid paint additive into the paint and
on with
a
reason to This
is
medium-nap "tip
roller.
(There
is
roll
it
never any
out" the paint on a nonskid surface.)
the easy
way to
introduce
but because the additive
grit into
the paint,
— usually polymer beads
tends to settle to the bottom of the paint
tray, dis-
persion of the grit on the painted surface can be irregular.
For a
more
aesthetically pleasing result,
first
coat the nonskid area with an epoxy primer and
cover the wet epoxy with gers or a large shaker.
sweep
off the grit that didn't
on another nonskid that remains with
52
grit sifted
from your fin-
When the epoxy
area),
two
DECK REPAIRS
kicks,
gently
adhere (you can use
and encapsulate the
rolled-on coats of paint.
it
grit
RUBBERIZED OVERLAY For the best footing, you
may want to
consider a
rubberized nonskid overlay, such as Treadmaster
good choices
or Vetus deck covering, also
for
M
com-
worn-out nonskid textures. For
pletely hiding old,
overlay application, carry the paint V2 inch into the
nonskid area
when you
paint the deck.
Preparing the surface. Eliminate all molded texture. Most
of
can be quickly
it
taken off with a disk sander and a 36-grit
disk. (A belt
sander can also be used.) Be careful not to get outside the textured area. desirable to grind
away all the
depressions with epoxy putty.
sand the surface to
fair
It is
pattern.
When
the sander
Fill
the remaining
the epoxy cures,
and prepare
it
let
neither necessary nor
it
for the adhesive.
Cutting patterns. /
Make
1
a pattern
from
oversize, then place
cut
in
kraft it
on deck to trace the exact
the center of the paper to hold
it
lid
leave at least
between adjacent
nonskid and
1
inch
rails,
avoid confusion
A
in
place.
Use
Tape across holes
a flexible batten to
Jff
draw
uniform corners. For appearance and drainage,
curved edges, a can
for
outline.
coamings, or cabin
when you
sides. Write
cut the overlay, and
ll\
between the
panels, at least twice that
u
"TOP" on the pattern to
draw
a line
on
it
parallel to
\
°
paper for each of the nonskid panels. Cut the paper
//
i\i
"^Wx |\\\ TOP
\\\
[Wm ^yL^\\
the centerline of the boat, with an arrow toward the bow.
1
ICmlK ["ivA Do
not cut patterns for only one side, expecting to reverse
them
for the
opposite panels. Boats are almost never symmetrical, and hardware to be
in different locations.
Cut a separate pattern for every panel.
the patterns have been cut, tape effect before proceeding. Trace
them
all in
certain all
place and evaluate the overall
around each pattern with
the deck area to be coated with adhesive.
is
When
a pencil to outline
1^
RENEWING NONSKID
i-
53
Cutting the overlay. Place the patterns topside
1
ial.
Position
down on
the back of the overlay nnater-
the patterns on your material to minimize the waste
all
before making any cuts. Depending on the overlay you have chosen,
it
may be
necessary to align the patterns; use the line you
drew on eaCh pattern
for this purpose, aligning
it
parallel to the
long edge of the sheet of material. Trace each pattern onto the overlay.
Cut out the pieces with
tin snips or
heavy
scissors.
Applying the overlay.
on
Pick
the deck and press
flat,
putty knife, and clean
adhesive, glue the nonskid to
beginning with pressure
the deck with thickened epoxy.
the middle and working
dampened
Coat both the outlined deck
outward to
applying each section
the overlay manufacturer
area and the back of the nonskid with the adhesive, using a
serrated trowel.
54
up any squeeze-out with
Position the nonskid
doesn't specify a different
If
1
>>
DECK REPAIRS
all
it
edges.
in
residue with an acetone-
until
all
cloth.
Continue
are installed.
a
away the
in
turn
TEAK DECKS CLEANING Left untreated, good-quality teak
would normally weather to an
attractive ash gray, but the assault of
turns bare teak nearly black. Clean
does the job.
Start with a
it
modern-day
air
pollutants
with the mildest cleaner that
75/25 mixture of liquid detergent and
chlorine bleach (no water), boosted with TSP. Apply this with a brush, scrubbing lightly with the grain. Leave the mixture
wood dirt,
for several
stiff
on the
minutes to give the detergent time to suspend the
and the bleach time to lighten the wood, then
rinse
thoroughly
by flooding and brushing.
LIGHTENING As good as chlorine socks,
it's
you need
is
at bleaching cotton sweat-
not a very effective oxalic acid.
wood
You can get
bleach. For that
by buying a
it
commercial single-part teak cleaner the active ingredient
in
most
— oxalic acid
is
— or for about one-
tenth the price you can buy a can of Ajax house-
hold scouring powder. Whichever you select, brush
the cleaner onto wet teak and give
then scrub the
wood
it
time to work,
with Scotchbrite or bronze
wool. (Never, ever, ever use steel wool aboard your
boat
—
it
will
leave a
trail
of rust freckles that will be
impossible to remove.) Oxalic acid dulls paint and fiberglass, so
before you
wet down surrounding surfaces
start,
and keep them
Rinse the scrubbed
wood
free of the cleaner.
thoroughly; brushing
is
essential.
For potential treatments for teak decks, see
Boat Refinishing
in this series.
TEAK DECKS
>-
55
TWO-PART CLEANERS Two-part teak cleaners are dramatically effective restoring the color to soiled, stained,
at
and neglected
teak, but these formulations contain a strong
acid
— usually hydrochloric — and should only be
used
when
all
other cleaning methods have
Wet the wood
1
to be cleaned, then use a nylon-bristle
brush to paint part
1
onto the wet wood, avoiding
contact with adjoining surfaces. bristle brush, is
I
failed.
the cleaner
will
If
you use
a natural-
dissolve the bristles;
it
doing the same thing to your teak.
Scrub with the grain.
Part 2 neutralizes the
acid in part
usually has
1
and
some
cleaning properties. Paint sufficient part 2
onto the teak to get
a
uniform color change.
Scrub
56
>-
DECK REPAIRS
lightly.
Flush
away
wood
dry.
a//
traces of the cleaner
and
let
the
SURFACING After a
number
of years, bare teak decks
This unevenness traps dirt
become rough and
and harbors mildew, making the deck
harder to clean and harder to keep clean. The solution the deck with a belt sander, using a
moving
at
all
times,
ridged.
and sand
at
1
20-grit belt.
about
1
5° to
is
to resand
Keep the sander
the grain.
RECAULKING The
instructions that follow are for recaulking a sec-
tion of a single seam, but the steps are the
same
for
an entire deck.
With a razor
1
knife, cut
the seam caulk at a diagonal a
couple of inches beyond the bad section, then
slice
the section to be replaced free from the planks on either side, taking care not to nick the
wood.
Dig out the old caulk. This
made by about
heating the
90°.
planks,
When
tail
every
vacuum the
is
of a
bit of
much file
easier with a rake
and bending
the old caulk
is
it
off the
scrapings out of the seam.
TEAK DECKS
>
57
A
Use an acid
Mask the
sur-
brush or a
face of the
Q-Tip to
planks.
thoroughly
prime both plank edges.
Use the primer
recommended for the caulk
you are using.
Two coats are generally required.
The
"right" caulk for
deck seams
is
two-part polysulfide. Mix the catalyst
into the sealant per label instructions, taking care not to introduce bles,
then
fill
an empty caulk tube with the mixture. (For limited
a single-part polysulfide will also give
good
convenient.) Cut the tip of the tube and
When the entire seam into the
is
seam by dragging
IDENTIFYING DECK CAULKING FAILURE HOW DO YOU KNOW WHEN THE SEAM caulking on a teak deck has released
its
grip
on the wood? The wood usually tells you. On a sunny day, scrub the deck, then keep it wet for half an hour or so before letting it dry. Areas along the seams that stay wet longer than the rest of the deck are suspect; spots that stay dark a
lot
longer definitely
indicate caulk failure. Using the point of a knife,
you
will
see that you can separate the
caulk from the wood, and the
plank
will
be wet. Repair
before they result
in
edge of the
"flagged" seams
bigger problems
beneath the teak.
58
all
DECK REPAIRS
the seam from the bottom.
a putty knife over
Remove the masking
knife,
but
it
repairs,
and may be more
slightly overfilled with sealant,
hump up slightly behind the cures.
fill
results
bub-
will
it
firmly.
compress
The sealant
it
will
shrink almost flush as
carefully while the caulk
is still
tacky.
it
BUNG REPLACEMENT The most
common problem
popped bungs. Years
of teak decks
Just tapping a
is
of scrubbing thins already-
thin overlay planks until the grip of the
bungs
is
new bung
rary repair at best. cial
in
place
will
be
a
tempo-
Deck overlay bungs require spe-
procedures.
insufficient to hold against flexing or expansion.
Remove and rebed the screw
1
in polysulfide.
Deck
core problems often occur beneath teak overlay
because the screws holding the overlay penetrate the top skin of the deck. Always rebed exposed screws.
It is
a
good
idea to check the core for
sponginess with a piece of wire. (See "Core Problems.")
•^
Reduce the plug bevel.
In a
shallow hole, you
Use a Q-TIp to wipe both the hole and the plug with
cannot afford the generous bevel found on most
acetone to remove surface
commercial teak plugs; sand the bottom of the plug
install
to reduce
it
to the bare
oils.
Wait 20 minutes to
the plug.
minimum.
TEAK DECKS
-j^
59
—
COLLOIDAL SILICA (FILLER)
Mounting
a plug
permanently
in a
After the
shallow hole
epoxy
is
dry, place
the point of a chisel
down — against the
plug about Vs inch
requires the tenacious grip of epoxy glue. Paint the
beveled side
hole and sides of the bung with unthickened epoxy.
above the surface of the plank and tap the
chisel
Thicken the epoxy to catsup consistency with
with a mallet. The top of the plug
away.
(colloidal silica)
plug. will
will split
and coat the sides of the hole and
Tap the coated plug
go.
filler
into the hole as far as
Wipe up the excess
it
glue.
Working from the lowest edge of the trimmed plug, pare
away the plug
until
it is
nearly flush with the plank. Finish
the job by block sanding the plug with paper.
60
>-
DECK REPAIRS
1
20-grit sand-
PLANK REPLACEMENT Occasionally a teak plank splits or
damaged and
is
otherwise
requires replacennent.
More often
teak overlay problems have an underlying cause usually a
wet core
— and to effect repair the teak
must be removed. Since the cause of the leakage
some
boat-
elect not to replace the overlay, but
most
often turns out to be the screw holes,
owners
are unwilling to give
teak decks.
A
up the beauty and footing of
careful installation minimizes the risk
to the core.
If
1
you are replacing more than
ber and Crosshatch
all
a single plank,
num-
the planks to be removed so
you can put them back properly.
/
J 9
[i^
—
r
\
1 I
'i:',";i;';'i!:'.i',i' iM/i'', With bungs removed (carefully
if
you
will
be reusing the
the screws. Slice the plank free of the caulking
all
plank), extract
around, and pry the
plank up from the bedding compound, using a block under your prying tool to protect the adjacent plank.
organic it is
compound,
bedded
should slowly
in polysulfide,
plank to remove rest of
it
it.
you are
If
the plank
pull free
likely
—
is
like a
bedded
an
in
gum-stuck
to have to destroy the
heel.
If
first
With side access, you should be able to separate the
the planks from the deck with a thin, sharpened putty knife. A
length of steel leader wire connected to two lengths of dowel
times effective
in
is
some-
"cutting" deck planks free.
TEAK DECKS
>
61
Scrape and sand away
all
old bedding connpound.
If
the core
is
dry, protect
of epoxy. Give the
epoxy
it
a
by injecting the hole
full
few nninutes to saturate
the edge of the core, then draw out the excess with a small
brush or a
stick.
For greater security,
drill
each hole oversize and, after painting the sides with unthickened epoxy,
ened with redrill
62
>-
fill
each hole with epoxy thick-
colloidal silica.
When the filler hardens,
the center for the screw.
DECK REPAIRS
If
you are
installing
new
planks,
fill
holes with epoxy putty, but don't
the
new
plank Into position, then
the deck. Counterbore the hole
in
half the plank's thickness but not thirds.
Epoxy the new holes
two methods just
detailed.
in
the old screw
redrill drill
them.
Wedge
the plank and
the plank at least
more than two-
the deck
in
one of the
Wash the deck and the underside
of
the plank with acetone. For better adhesion, prinne the teak. Coat the
deck with black polysulfide (two-part preferred) a
Hold or
down.
much
wedge the
plank
in
position
Select Philips-head screws less likely to
and screw
and you
damage the edge
will
of the
and
distribute
it
evenly with
saw-toothed spreader.
it
be
bung
hole with the screwdriver.
8
Install
bungs (with epoxy) and trim
them. Caulk the seams.
Belt
sand the
deck fair.
TEAK DECKS
5>
63
64
LAMINATE REPAIR
The
and deck
hull
— problems that can be fixed with a proper topical applica-
leak related
tion of
have either been cosnnetic or
repairs described so far
one glop
or another. But
sometimes the problem
is
below the
face: the original laminate lacks the requisite stiffness; moisture has
integration or delamination; or the glass fibers have
These problems require more extensive Fiberglass has of
its
of fiberglass boats.
healed with a
And the
it is
repair
is
repair.
repairability that
less
can of
patch than graft
material because
accounts for the near immortality
The most horrifying hole
bit of glass fabric, a
dis-
been broken by impact.
become the predominant boatbuilding
durability, but
caused
sur-
in a fiberglass hull is
resin,
and equal parts
quickly
skill
and
care.
— a new piece of skin indistinguish-
able from the old. Fiberglass lay-up can hardly be simpler.
It is
nothing more than layers of
glass fabric saturated with polyester (or epoxy) resin. With a paint brush, a
of water,
and
a piece of old T- shirt,
you can practice
all
the requisite
skills
cup for
fiberglass lay-up.
Don't misunderstand: because of blocked access or complex shape, lami-
nate repair cannot always be honestly characterized as easy, but such problems
what make most boatowners shy away from attempting a repair. It's the lay-up. Most boatowners imagine a self-applied laminate as only slightly more
aren't
durable than a wet Band-Aid. That
provided
in this
chapter
what you can expect
is
a false concern. Follow a
— and your lay-up
a yard to do.
And
it
will
will
few simple
rules
be as good as or better than
remain that way a decade
down
the road.
65
UNDERSTANDING POLYESTER RESIN Polyester
resin
is
the glue that binds glass fibers
into the hard substance
we
call fiberglass.
On
the other side of the Atlantic, the same product
— glass-reinforced
called
GRP
British
take
plastic.
is
As usual, the
more care with the language than we is exactly what it is.
do; glass-reinforced plastic Polyester resin, plastic
when
— not one of those tough plastics that
deflects bullets or that 1
catalyzed, hardens into
00 years
you can use as
a
hinge for
— but an amber-colored, rather seems more
plastic that
building material. But
like
when
brittle
combined with
sum
is
greater
than the parts. Polyester resins
come
in
(see sidebar), although
you
kind a particular brand
is
various formulations can't always
from the
priate for the repair
what
tell
label. Generally,
you don't need to know. When polyester (sometimes epoxy
is
appro-
resin
is
a
better choice), whatever laminating resin your
supplier carries should prove satisfactory. Below-
the-waterline repairs are the exception; avoid
rock candy than boat-
ortho resins
polyester resin
immersed.
is
glass fibers, the
if
the repair
will
be continuously
LAMINATING VERSUS FINISHING You do need to choose between laminating and fin-
1
ishing resin. Laminating resin
is
"air-inhibited,"
ing that the resin will not fully cure while air.
That
may sound
solidifies
mean-
exposed to
odd, but remember that polyester
not by drying,
like paint,
but by a chemical
reaction (called cross-linking) induced by adding a catalyst. Air interferes
with this curing process.
For any job that requires the laminates to be
applied
in
more than one operation, you need
lami-
nating resin. The fact that the surface remains tacky after the resin sets allows
you to apply the subsequent
laminates without any intermediate steps, and the
new application will one to form surface
a
link
chemically with the previous
LAMINATING
powerful chemical bond. For a tack-free
on the final
RESIN
application, coat the resin with
polyvinyl alcohol (PVA) or seal
it
.
AlRlNHlBlTfc'^
with plastic wrap.
Finishing resin
is
identical to laminating resin, but
with an additive that "floats" to the surface of the curing resin. This surfactant (once wax, but ally a
drying
oil)
seals the resin
from the
air,
now
usu-
thus
allowing the surface to fully cure to a tack-free,
•FINISHING ,„^ . '^'IR
66
>>
RESIN
NOT INHIBITED
sandable
state.
Use finishing
done
in a
be used
resin for laminate jobs that
can be
single operation. Finishing resin can also
for the final layer of a multilayer lamination.
LAMINATE REPAIR
I
r ORTHO,
ISO,
OR VINYLESTER?
FOR THE FIRST 30 YEARS OF FIBERGLASS BOAT MANUFACTURING, the only resin widely in use was orthophuntil fiberglass boats thalic resin. Ortho resin was cheap, easy to work with, and had no apparent failings
—
began to
blister.
Isophthalic resin, slightly it
more expensive, has largely replaced ortho resin in boat nnanufacturing because due to its higher solvent resistance. A packaged polyester resin sold
seenns less prone to blistering, probably
for repair work,
good
if it is
Vinylester has long
resistance, but
turers hulls.
its
be iso resin. performance boats because of its superior adhesion qualities and impact
quality, will likely
been used
in
superiority as a moisture barrier has led to
now use vinylester laminating
resin
and
more widespread
use.
Many new boat manufac-
produce
vinylester gelcoat in theii quest to
For repair work calling for polyester resin, vinylester's better adhesio. makes ,
it
a
blister-resistant
good
choice.
I. HOW MUCH The
CATALYST?
catalyst for polyester resin
MEKP
not confuse
with the
is
methyl ethyl ketone peroxide, or MEKP. Do
common
Polyester resin usually requires
low the manufacturer's ener
will
catalyze
1
solvent MEK; they are nof the same. to 2 percent of hardener by
1
ounce of
resin at
thoroughly or part of the resin
will
1
percent. Be certain to
weather, and the thickness of the laminate is
is
(fol-
the catalyst
all
less catalyst.
just as
of too
little
weak
lamination.
catalyst;
good \f
in
affect curing times.
about two hours
unless the wait
will
you add too much, the
is
probably
in
lay-up.
Temperature,
Some
experi-
generally required. The mix shouldn't kick (start to harden)
than 30 minutes. Hardening overnight
stir
be undercured, weakening the
You can adjust the cure time by adding more or mentation
volume
As a rule of thumb, four drops of hard-
instructions).
ideal,
in less
but
hold you up. Always err on the side resin will "cook," resulting in a
FIBERGLASS MATERIAL Fiberglass material
weave repair,
ing,
is
exactly
what
it
sounds
of glass fibers. For boat construction
the glass comes
and
cloth.
in
like,
a
and
chopped-strand mat, rov-
Chopped-strand mat. Chopped-strand mat is made up
of irregular lengths of
glass strands glued together randomly. Generally speaking,
CSM
the easiest fabric to shape, gives the best
is
resin-to-glass ratio, yields the
most watertight, and
is
smoothest surface,
is
the
the least subject to delamination,
but the short fibers do not provide the tensile strength of a
woven Mat
material. is
sold by the yard from a
ous weights designated
ounce mat
is
a
in
roll
and comes
ounces per square
good choice
in vari-
foot;
1
Vi-
for general use.
UNDERSTANDING POLYESTER RESIN
>-
67
-;:^;^^::^M^
Fiberglass cloth. Fiberglass cloth looks like shiny canvas but not tightly. Cloth
is
stronger for
its
prone to pulling and unraveling process,
Roving. Roving
parallel, flat
is
bundles of continuous glass
unwoven roving
stitched together;
parallel
in
straight,
in
woven
in
unwoven
roving
is
usually a better choice because
strength
in
two
full
strength
in all directions.
is
directions
is
a better choice for
commonly available
any, fiberglass
the direction of the strands but
roving
provides
Cloth
ounces. For any boat over
continuous strands
strength perpendicular to them. For hull and deck
repairs,
better.
While
most
repair work.
woven roving assembles the bundles
add excellent strength little
the laminating
and the finished product looks
and roving, mat and cloth
bundles are cross-
directions in a loose weave.
The
in
1
in
weights from 4 to 20
5 feet, there will
be
work that you cannot do with
mat and 10-ounce
cloth.
If
you have
1
a choice,
little, if
V2-ounce
buy 38-
inch width. it
and good
(You can accomplish the same
thing by rotating the orientation of alternating laminates of
unwoven
strength
roving, but unless
you need additional
in a particular direction,
using
woven
roving
is
OTHER MATERIALS
simpler.)
Roving laminated to roving, either unwoven or
woven,
is
unacceptably easy to peel apart. Always bind
layers of roving together
by using a layer of mat between
For most repairs, select 18-ounce roving. That
sound heavy
relative to
I
GLASS I5NT THE ONLY MATERIAL THAT CAN be combined with
resin. Increasingly,
1
may
V2-ounce mat, but don't be con-
Weight designations
for
mat
are per square foot,
while for roving (and cloth) they are per square yard;
ounce roving weighs the same
as 2-ounce mat.
1
8-
composites with special characteristics weight, rigidity (or flexibility), impact
als
include graphite (carbon
None of these deck
repair.
a material's strengths
you use
k LAMINATE REPAIR
light
resis-
fiber), Kevlar,
polypropylene, xynole-polyester, Dynel, and
cal hull or
>-
—
tance, tensile strength, or others. These materi-
ceramic.
68
boat-
builders are using "exotic" materials to create
each layer of roving.
fused.
as
less
manufacturers generally use alternating layers of mat
strands. In
two
woven
weight than roving,
it.
is
essential for the typi-
You should understand and weaknesses before
GRINDING During the lay-up form
IS
ESSENTIAL
process, each application of resin links chemically with the previous application to
a solid structure
— as though
deceiving; a better analogy
all
the layers were saturated at once. The layer-cake look of fiber-
Jell-0 salad
— the
may be
glass
is
solid.
Chemical linking between resin layers occurs because each layer
fully
is
cures (the reason for using air-inhibited
Unfortunately, no matter
how strong the
fruit
in layers, is
but the encapsulating Jell-0
applied before the previous one
resin).
laminate-to-laminate bond, the
initial
mechanical, not chemical. This need not weaken the repair as long as the surface
means
is
is
bond of any
repair
is
properly prepared. That
grinding.
Before grinding, always wash the area thoroughly with a dewaxing
1
solvent.
The
original fiberglass will
have traces of mold release on
the outer surface and wax surfactant on the inner surface. to
remove the wax
first,
surface scratches and
grinding
will
drag
it
into the
If
you
fail
bottom of the
weaken the bond. Protect your eyes
with goggles and
your lungs with a
good dust mask. A paper mask is inadequate for
all
but
the smallest grinding task. will
Long sleeves
reduce skin
irritation.
Outline the area of the
loaded with a 36-grit
bond and grind
disk. Tilt
inside the outline with a disk sander
the sander so that only one side of the disk
touching the surface and the dust
is
is
thrown away from you.
Brush away the dust and wipe the area with an acetone-dampened rag. The surface should have a uniform dull look;
if
any areas remain glossy, make
another pass over them with the sander.
GRINDING
IS
ESSENTIAL
'^
69
THE BASICS OF FIBERGLASS LAY-UP PREPARATION
Dewax and
1
applied later
grind the surface the lay-up
to. Specific
types of repairs
will
be
— detailed
— require additional surface prep.
Protect
all
surrounding surfaces by masking.
Waxing below the
repair area will
make
unantici-
pated runs easier to remove.
--
^^
-^-^i^^Mm^^^^
Cut the fiberglass pieces to the correct
them out
in
the order you
will
a rule, apply the smallest piece last.
70
>-
LAMINATE REPAIR
Always
start
and
finish
size
and
lay
be applying them. As first,
the largest piece
with mat.
APPLYING THE INITIAL LAYER
Catalyze the resin and mix
it
Hold the
thoroughly.
1
line
first
around
layer of fiberglass in place
It.
and
pencil a
Use a throw-away brush to coat the
outlined area with resin.
Apply the
first
layer of
a vertical surface, use fabric in place.
and press
it
Use
a
mat
to the wetted surface.
On
masking tape to help hold the
squeegee to smooth the mat
into the resin.
With a brush or a it is
roller,
wet the mat with
resin until
uniformly transparent. White areas are dry spots
and require additional
resin.
Brush or
roll
gently to
avoid moving the fabric or introducing bubbles.
THE BASICS OF FIBERGLASS LAY-UP
71
ADDITIONAL LAYERS
Apply the next layer
1
the saturated mat.
— cloth or roving — on top of
Smooth
it
against the mat with a
Wet out the grooved any
squeegee.
air
cloth with resin. Use a
roller
to
squeegee or
a
compact the laminates and force
bubbles to the surface. Remove excess
resin
with the squeegee.
If
the weather
is
cool or the repair area
is
can apply up to two more layers without cure generating so
much
heat that
or warps the repair.
72
>-
LAMINATE REPAIR
it
small, risk
you
of the
cooks the resin
Allow the resin time to apply two
(or
process until
gel,
then mix fresh resin and
more) additional all
layers,
repeating this
the layers have been laminated.
FINISHING For a smoother
1
finish, roll
After the last coat
an
of resin kicks,
additional coat
brush or spray on
of resin over the
an unbroken coat-
final layer of
ing of polyvinyl
material.
alcohol (PVA) to seal the surface so it
will
cure
This
isn't
sary
if
fully.
neces-
you use
fin-
ishing resin for
the
last coat.
WORKING OVERHEAD Alternative application
1
techniques are required to laminate fiberglass
overhead. Mix a small batch of
more
resin,
adding
catalyst than usual,
and use
it
to
wet the
repair area.
For an overhead repair, always work with small pieces of fabric. Roll the
mat onto
a
dowel or
a
cardboard tube, and wait for the resin to
edge of the mat and
surface feels tacky, carefully position the
keep
it
smooth. The tacky
fresh resin.
Use
a roller or
resin will hold the
squeegee to
mat
in
piece of
start to kick.
unroll
it,
When
the
taking care to
place while you saturate
it
with
distribute the resin.
When
the surface of the mat
the next layer of fabric onto
keep
it
Repeat are
first
smooth. Saturate this step for
is it,
tacky,
this layer
each layer
you can
unroll
again taking care to with fresh resin.
until
all
the laminates
in place.
THE BASICS OF FIBERGLASS LAY-UP
73
WHEN TO
USE EPOXY
Epoxy is almost always better than resin for repair
bond job
—
forms
it
worth the
work because the mechanical
— the weakest
stronger. Laminate
is
also superior
less significant,
polyester
link in
made
Do not use epoxy
any repair
with epoxy
is
is
more than twice
of polyester, manufacturers rarely use nating. For repair
it
if
polyester, the reverse
epoxy
for lami-
repair will not
for boatbuilding.
The
two most common brands are West System (Gougeon Brothers) and System Three, but there are others. The main difference you are likely to notice between competing brands
tend to make
the mix
is
ratio,
but metered
this difference of
pumps
consequence.
little
ADDITIVES For saturating fiberglass laminates, use the epoxy as
course
— but
bonding and
for
cific characteristics.
filling,
short fibers for small putty needs, but for fillers
are easy to mix, provide
Microballoons. Microballoons produce ily.
a fairing
comes
it
and
for filling
good
more than strength,
for
hull
and deck
it
spe-
repairs.
bonding where there
is
a
glass cloth diagonally to generate
that
buy packaged microfiber filler.
and have excellent finish
are tiny hollow beads of plastic.
compound, microballoons
— catalyzed, of
epoxy and give
Three of these are especially useful for
gap between the surfaces being bonded. You can snip
Fiber
it
additives thicken the
Fibers. Fibers added to epoxy will thicken
Added
yield a putty that spreads
to
properties.
epoxy to
and sands eas-
Microballoons reduce the strength of the epoxy and should not be used for bond-
ing or laminating. Also avoid using microballoons below the waterline because the resulting putty
is
porous and
Colloidal Silica.
Silica is
than microfibers and
it
will
absorb water.
perhaps the most versatile of fillers.
74
5^
It
provides better strength
doesn't affect the permeability of the cured epoxy.
thickened putty cures with a rough texture and
LAMINATE REPAIR
resists
is
will
be finished
not true; the bond
be gelcoated, use polyester
is
Don't buy epoxy by the tube.
epoxy formulated
the repair
be strong.
SELECTING EPOXY
Select an
well
between polyester gelcoat and an underlying
that
work the additional expense
is
with gelcoat. While epoxy bonds tenaciously to
— stronger and more durable — but
because the cost of epoxy
and the added strength
cost.
abrasion
Silica-
— including sanding.
If
the surface
will
resin for the repair.
MIXING Metering pumps. While polyester requires only a few drops of catalyst per ounce of resin to start the chennical reaction, the combination ratio for epoxy is much less one-sided. The resinto-hardener ratio
is
some formulations
typically at least five to one, but call for a
two-to-one mix. Epoxy man-
ufacturers typically have calibrated will
to
meter out the correct
one pump of
resin.
ratio
Epoxy
so the purchase of metering
mended. flat
Stir
mixing
is
pumps
available that
— one pump of hardener very sensitive to mix
pumps
is
ratio,
strongly recom-
the two parts together thoroughly, using a
scrape the sides, bottom, and corners
stick to
of the container.
Regulating cure time. Unlike polyester, the cure time of epoxy cannot be
adjusted by altering the fied proportion of
amount
of hardener.
—
./"'^
speci-
hardener must always be used.
However, epoxy manufacturers generally
two hardeners
The
fast
and slow
offer at least
— and they often have
additional hardener formulations for special require-
ments, such as tropical use. Pot temperature, but you
will
life
varies with
quickly learn
available. Limit batch size to the
ambient
how much
amount
of
time
is I
epoxy you
1
can use
in
that
amount
pot, so the quicker
to
work
of time. Epoxy cures faster
you apply
it,
the longer you
will
in
the
\
have
it.
W
Thickening. Always add the thickening agent after the resin and hardener have been mixed. Stir in
^^^tfrH
the thickener until the
®
\}
^= (D
^-x-^
^^^^ (-yr-
MICROBM
1
®
mixture reaches the desired consistency.
''
Y
WHEN TO
USE EPOXY
75
PRECAUTIONS People to
in significant
numbers develop
epoxy so that any exposure
tion
and
course.
Avoiding
rash.
Wear
all
a sensitivity
results in skin irrita-
skin contact
plastic gloves
the safest
is
when working
with
epoxy. Goggles are reconnmended.
Avoid breathing the fumes of curing epoxy. Be sure you have
good
ventilation.
The heat generated by curing epoxy to melt a plastic container
flames
if
you leave the mixture
—
until
sufficient
ignite into
the pot too long.
in
the mixture begins to heat up, put
from anything flammable
is
and may even
it
it
outside
If
— away
cools.
LAMINATING WITH EPOXY Do not use chopped-strand mat when
1
laminating
with epoxy resin. The binder holding the strands
may
together
react with the epoxy, affecting both
the adhesion and the permeability of the epoxy.
Epoxy
is
a strong
enough adhesive
cloth without risk of delamination,
to bind cloth to
and multiple
lay-
ers of fiberglass cloth create an extremely strong
laminate.
^?^