| Preliminary Info |
Before you tune the rig to these numbers make sure that the
head of the spar is centered over the boat. Hoist the tape measure
on the main halyard, measure from port chainplate to starboard
chainplate. The number should be the same (to within 1/8th inch.)
Once you have centered the rig, then proceed with setting up
the rig to the following numbers. |
| J Measurement |
11' 6"
Make sure your mast is blocked all the way aft in the partners.
With the tape measure pinned at the intersection of the forestay
and the stainless steel stem fitting at the deck, the front
edge of the mast should be as far aft in the partners as possible.
11' 6" is the maximum legal "J" dimension and is most desirable
for inducing some weather helm and enhancing pointing ability. |
| Headstay Length |
35' 10 1/2"
A pair of binoculars will come in handy to sight up to the hounds
(forestay attachment point on the mast). Measure this by hoisting
a metal tape measure up on the spinnaker halyard so that the
tape is even with the headstay pin. Then measure down, along
the headstay, to the stainless steel plate on the deck. (not
to the forestay clevis pin) |
| Mast Butt Position |
With the headstay at max. length of 35'-10 1/2" and the mast
blocked all the way aft in the partners for maximum "J" dimension,
position the mast step so the mast is straight fore and aft
with slack shroud tension (no pre-bend). When the following
shroud tension numbers are used they will induce minimal lower
mast pre-bend and a total pre-bend of 1.5 - 2". This will transfer
more load to the headstay for a tighter headstay and better
all around windward performance. In addition it will make the
mast bend top-loaded. This will make for a powerful mainsail
in lighter air when minimal backstay tension is applied. As
the breeze builds and you need to "shift gears" and flatten
the sails, increasing backstay tension will tighten the headstay,
flattening the jib and will flatten the mainsial and twist off
the top of the main providing a smooth progression from fully
powered-up to de-powered. |
| Shroud Tension |
Uppers: 44 - 45 on the Loos Tension Gauge.
Lowers: 45 - 46 |
| Helpful Hint |
Pull the backstay on to maximum before you try to tighten
the upper and lower shrouds. Doing this will pull the masthead
aft in the boat, easing the tension on the shrouds and making
it easier to increase tension on the rig. Just make sure that
you ease the backstay off when you check your rig tension numbers
on the Loos gauge. |
| If you tune to these numbers you
will have a pretty tight rig. With the backstay all the way
eased you should have about 1.5 - 2.0" of pre-bend. The headstay
should be just barely snug. This should provide enough headstay
sag to power up the genoa for all but the lightest sailing conditions.
As the breeze increases so will your backstay pressure. This
will increase headstay tension and flatten the entry of the
genoa. As you probably know, the J/30 is power-hungry. You won't
have to use much backstay as the boat can use as much power
as it can get. Until the wind howls and you're well into the
#2 and #3 jibs you will use backstay sparingly. |
