Hunter 28.5 Manual page 4

HUNTER
TUNING THE
B&R RIGGING
NOMENCLATURE DESIGNATION
upper-upper
D3*
lower upper
V2
lower intermediate
V1
lower D1
upper intermediate D2*
lower diamond dl
upper diamond d2
•D2 and D3 are cut to a fixed length (no
turnbuckles).
Initial tuning is best accomplished
before the mast is stepped.
Support the mast, forward side down,
about 1/4 of its length from the end and
at its center. Once the mast is supported,
make certain that it has no bow in any
direciton. Attach a small string from the
masthead, in line with the sail track
groove, to the base of the mast, stret-
ching it as tight as possible. Check to
make sure it is a constant distance from
the mast along the entire length.
You are now ready to "tune in" the
desired mast bend, which is 1% of the
mast height above the boom (.01 x mast
height above boom). On a 50' mast, this
would be .5 feet at the mid point of the
mast.
Using the rigging diagram, locate dl
and d2. Before tuning, make sure the
turnbuckles are adjusted back with equal
thread showing. Carefully counting turns,
adjust dl port, dl starboard, d2 port and
d2 starboard evenly until the desired
bend is induced. This is checked by
measuring from the string down to the
mast at the center of the mast.
It is Important to make sure the mast
is straight athwartships at this time.
You are now ready to step the mast.
Step the mast with all shrouds loosely
attached.
Adjust the forestay and backstay to
obtain the desired mast rake. The mast
should be vertical or raked aft. The more
rake, the greater the weather helm. The
forestay and backstay should have a
reasonable amount of tension on them.
Adjust V2 (port and starboard) evenly
until they are tight. You should finish with
approximately equal amounts of thread
showing on each turnbuckle.
Using the jib halyard, check the mast
for athwartship plumb. Pull the halyard
out to the side of the boat and below the
shear. Repeat the procedure on the op-
posite side. If you find a big difference
(more than 1/2") adjust turnbuckles an
equal amount in opposite directions until
the mast is straight.
Adjust V1 (port and starboard), using
the above procedure.
Repeat for D1 (port and starboard).
Your mast should now have the
original "pre-bend" and be straight
athwartship.
Check the mast tuning by sailing in
medium winds (10-12 knots). Sail on
both tacks, sighting up the luff groove to
check athwartship straightness. Shrouds
should not
be
loose on the leeward side.
When mast tuning is complete, install cot-
ter pins in all turnbuckles and tape over
sharp edges of the cotter pins with chafe
tape.
•