Performance Cruising Gemini 105Mc - Boom

Gemini 105Mc Owner’s Manual
23Copyright © 2004 Performance Cruising Inc.
shrouds should move about 2".
The checkstays do not need to be tight at all be-
cause they only serve to stop the mast from pumping
when beating to windward. For racing, the clevis pin
securing the turnbuckle to the pad eye can be re-
placed with a quick release 3/8 pin, for down wind
disconnection.
The mast is normally set vertical. Moving the mast
does not seem to affect the helm.
With the Gemini 105Mc the mast is raised 1’, in-
cludes a 1’ crane on the top, and the boom is ex-
tended 1’ compared to older Gemini models. (The
older masts were 38’ off the deck; the 105Mc mast is
39’ off the deck)
The forestay meets the mast at the 38-foot mark
leaving a foot above it for the optional “roller
screacher”, which is basically a roller-furling drifter.
This is an excellent option for the cruiser that does-
n’t want to bother with a spinnaker in light airs. The
screacher option includes supporting hardware con-
sisting of a mounted track that curves from one bow
to the other across the bowsprit. The base of the
sail can travel over the track and be brought to
windward.
The main sail has also changed with this 105Mc mast.
The crane provides for a much larger mainsail and
helps in obtaining maximum drive out of the top of
the sail. With this crane we can have a large roach
mainsail. However, so the sail doesn’t get caught up
in between the backstays, there is a single backstay
with a tensioner about 15’ up. The backstays only
need to be tensioned during up wind work and should
be slack at the dock.
Boom
The boom is 15ft. long and is secured to the mast at
the gooseneck with a clevis pin. The boom has three
pulleys at the stern end and three jam cleats at the
underside of the boom at the gooseneck end.
The starboard pulley and jam is for the first slab
reef. The second pulley is for the out-haul. The third
pulley is for the second reef. The sail that comes
with Gemini has slides on the foot so that the end of
the slab reefing line can be tied around the boom.
The first slab reef is between the second and third
slider from the end while the second slab reef is
between the fourth and fifth slider from the end.
The main sheet goes to a triple block shackled to the
under side of the boom. On the mainsheet track on
the combing is a slider with a triple block, becket
and jammer. The main sheet runs to the triple block
with the becket and jammer on the center pulley,
there is no means of feeding the lines without them
crossing.
The boat comes standard with lazy-jacks. On the
underside of the boom are two padeyes at 5-foot
increments. A 12-foot line goes between these pad-
eyes either side of the boom and is attached to a
line that goes to a pulley 5 foot below the upper
spreader on the mast. These single lines go back
down to cleats by the boom. With this configura-
tion, the lazy-jacks can be tensioned by the cleat or
removed when sailing.
Mast Rigging