Performance Cruising Gemini 105Mc - Care and Cleaning of Fiberglass

Gemini 105Mc Owner’s Manual
44Copyright © 2004 Performance Cruising Inc.
Blisters on the Deck or Interior
It is possible that with use, small parts of the gel-
coat on the deck or interior may chip away like an
eggshell, exposing a dark void below the skin. These
are not structural and go with the territory of a
hand made fiberglass product. The surface area of
Gemini is 600 square feet with every inch hand-
rolled. When the polyester resin is applied over the
fiberglass mat, because of the initial stiffness of
fiberglass mat, air is trapped below the mat. The
mat is saturated with polyester resin and rolled
with a small metal roller into all the corners. The
air is rolled out from under the mat. If in places the
air is not detected and is left under the mat, the
trapped air is a void that will expand or break out
at some time in the future. There is no way these
voids can be produced with time. All the voids are
there to begin with.
Any voids should be opened out completely and
ground. The surrounding gelcoat should be sanded
with 120-grit paper in a ring 3/4" around the void.
The void can then be filled with a catalyzed
Cabosil/Gelcoat paste. The paste is catalyzed with
2 to 5 % of MEKP liquid catalyst and trowled into
the void. Cabosil is a very fine powder of fumed
silica that magnetically holds together when mixed
into gelcoat. The resulting non-drip paste is very
fine so the cured paste can be polished just like the
original gelcoat.
Unfortunately, as the paste cures it shrinks
slightly; so either excess paste is applied or the
void is filled level three times after hardening. This
paste, because it shrinks when curing, is not advis-
able below the water. The water can enter through
the void left between the shrinking paste as it
cures, and the side of the void. The cured paste is
sanded almost level using 120 grit paper (80 grit is
acceptable providing this paper is only used to re-
move excess and then 120 paper is used to bring
down close to level. 180 then 360 paper is used to
level and finely sand the repair. The repair is then
compounded to gloss the repair like the surrounding
gelcoat. The reason for sanding 3/4" around the
void before applying the paste is to blend the repair
into the surrounding gelcoat.
Care of Cleaning of Teak
All interior teak on the Gemini is covered with sev-
eral coats of Tip Top teak oil. The teak oil is ap-
plied with a rag and simply wiped over the teak.
The surrounding surfaces are wiped with a clean rag
to remove the excess teak oil.
Mat varnish is another possible treatment for the
teak. This is a time consuming process as all the
teak has to be masked and the surface must be
sanded between coats. At least 3 coats must be
applied. The factory does not provide the option of
varnishing the interior teak wood.
Window Care and Treatment
The windows around the cabin are made of Lexan®
polycarbonate MR10 with a chemical and scratch
resistant surface. These windows should be washed
with only warm soapy water. The pilothouse win-
dow is clear while the other windows are a grey-
smoked color (Color #2074). Should you ever want to
replace a window, Lexan sheets can be purchased
from your local plastics supplier.
If the film on the polycarbonate is broken, chemicals
will degrade the polycarbonate. Polycarbonate will
expand 1/16" per foot. Therefore an 8' window will
expand 1/2". Fortunately, the surrounding surface
will also expand a little. The expansion can make
maintaining a proper seal around the window diffi-
cult. The Gemini’s windows are sealed with a GE or
Dow Corning silicone. The secret to the success of
this material is to get the silicone at least 1/8" thick
between the window and the cabin sides. This is
achieved by creating a silicone dam on the insides of
the screws. Liberal amounts of silicone are applied
between the dam and the edge of the window under
the window. The excess silicone is wiped off, and
previously applied masking tape is removed leaving a
straight line with the silicone tapering out from the
window.
Lexan MR10 Do’s and Don’ts
x Don’t clean with gasoline, Benzene, acetone, or
carbon
x Don’t clean with abrasives or highly alkaline
cleaners
x Don’t ever attempt to clean by scraping with
squeegees, metal, or a razor
x Don’t clean in direct sunlight or highly elevated
temperatures
x Do clean with Joy, Top Job, Windex with Ammo-
nia D, Palmolive Liquid
x If necessary, do remove stickers with kerosene
No maintenance is required for the window seal.
Care and Cleaning