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ETCHELLS
TUNING GUIDE
RIG
SET-UP
TUNING
WHILE SAILING
SAIL
SETTINGS AND CONTROLS
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Etchells
Tuning Guide
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Main Tuning Matrix
RIG
SET-UP
MAST
STEPPING:
Before stepping your mast, insert a piece of mylar between the
I-beam and underside of the plate with grease to allow the mast
step to be adjusted easily under load. Also, check that your mast
is not kinked or that the tip is not hooking off to one side or
the other. If it is, straighten it or have it straightened by
a professional.
To locate the position of the mast step,
hold the end of your tape measure near the centerline intersection
of the stern deck and the transom. Then run the tape forward over
the traveler through the console to the bottom, aft edge of
the mast. This distance should average from 17' 5.5" to
17' 6.25". On boats fitted with adjustable mast steps
the range of adjustment should be from 17' 4.5" to 17'
7".
UPPER
& LOWER SHROUD POSITION:
Once the mast is stepped, for most conditions (under 16
knots) attach the upper shroud turnbuckle to 2nd hole from the
front on the chainplate, and the lower shroud in the 4th
hole from the front (don't tighten yet). For heavy air,
attach
your upper shroud turnbuckle in the 3rd hole from the front of
the chainplate. If your spreaders are fixed straight or swept back
you may need to jump the uppers behind the lowers to the 5th hole
from the front. This will help keep the mast from over bending at
the spreaders in heavy air.
HEADSTAY
& MAST RAKE:
Before attaching the headstay hold it taught along the front
face of the mast and mark the headstay at the point that
corresponds to the upper edge of the black band at the gooseneck.
Once you have attached your headstay, adjust your turnbuckle
so that the reference mark is 46.5" to 47" above
the deck measured along the forestay. This determines the proper
mast rake.
Ideally,
you have an open barrel headstay turnbuckle (must be below deck,
class rule), and an above deck
fork-eye connection. This way you can adjust your headstay above
deck without having to climb into the bow tank. Your headstay
turnbuckle should have only one cotter pin to prevent the barrel
from spinning off while sailing. We recommend determining a base
headstay setting 46 3/4" to 47 1/2" that works for your
boat. From that base setting you can tighten the headstay
1/4" for heavy air and loosen 1/4" for light air.
UPPER
& LOWER SHROUD TENSION:
Now you're ready to tension the shrouds. Before you do, pull
the backstay so that the headstay is just taught and remove all
the aft chocking at the partners, and insert full forward chocking,
which will eliminate any pre-bending of the mast. Begin by tensioning the upper shrouds evenly so that when you sight the
mast slot it is essentially straight side-to-side. Tighten the
uppers to 17 on the
Loos
PT-2 gauge
for starters. Then
tension the lowers evenly hand tight so the mast is straight side
to side. Since the lower tension varies so much depending on the
wind speed, the goal is to start with them even before sailing and
adjust them for the conditions on the race course. Make sure to
tie off or lock off your turnbuckles each time before and while
sailing or the turnbuckles could spin off on their own.
TUNING
WHILE SAILING
Unless you are sure what the conditions will be on the race course
or it is extremely windy, I generally recommend fine tuning the
shrouds, mast step and mast chocking while tuning up before the
start of the race. Remember the Etchells class rules allow you to
adjust your shrouds, backstay and mast chocks while racing but
prohibits adjustment of the mast step and headstay while racing.
For wind speeds 10 to 15
knots, leave the uppers at 17 on the Loos
PT-2 Gauge. For heavy air, tighten the uppers to
20 on the gauge. For wind speeds below 10 knots, the uppers should be loosened
to 15 on the gauge.
Begin by sailing close hauled with the mainsail and jib
sheeted in properly. Next, pull the backstay enough to firm up the
headstay. Then you must decide to change a few key adjustments
based on the wind speed, the mainsail and jib
cross-sectional shape and the sideways mast straightness.
First
make sure the leeward upper is not too slack or too firm while
sailing closehauled. Once you have adjusted the upper tension
equally, it is probably a good idea to check the mast straightness by
sighting the rig, while it's loaded on a close hauled course. If
the mast is sagging to leeward at the spreaders more than 1",
then the lowers should be tightened evenly (some sag can be good
in lower wind speeds). If the mast is lifting at the spreaders and
there is less than 18 knots of wind, then the lowers should be
slackened evenly until the mast is at least straight.
MAST
CHOCKING:
Mast chocking at the deck is the next adjustment and probably the most
critical.
If after you have tensioned the backstay to set the desired amount
of headstay sag / firmness and the mainsail camber depth looks
wrong, then you'll need to adjust the mast chocking at the
partners. (This is when a good for'n aft mast under deck tackle
system is essential.) Quite simply if the mainsail looks
too full, add chocking behind the mast (typically necessary in
lighter wind speeds - inducing pre-bend). If you find you are
needing more than 1" of chock behind the mast, then your
mast step is probably too far forward. Once again after each mast
chock adjustment, check the jib trim and headstay tension and
adjust the backstay accordingly to achieve the proper headstay
tension as the wind speed varies so that the jib is set perfectly.
If you have too much chocking behind the mast the mainsail
will develop overbend wrinkles from the mast toward the clew.
In which case you'll need to add more chock in front of the mast
and/or move the mast step forward if you are already fully chocked
aft. As a general rule of thumb, I like to see the wrinkles in
the lower luff of the mainsail stop at about 50% camber
position (middle of the lower aft window in the main).
SAIL
SETTINGS AND CONTROLS
JIB
SETTINGS: Jib shape is the most critical on the Etchells.
The cross-sectional shape is largely affected by headstay
tension (the amount of sag).
To get the most low wind range out of your headsail, you can
induce fullness, power and pointing by easing the
backstay to sag the headstay a bit more and at the same time
slacking (scalloping) the luff tension by easing the adjustable
tack. This will help move the extra fullness back to the proper
draft position. If you have too much sag, the jib will actually become too flat and knuckle forward, which defeats the
purpose (wrong foil shape).
To get the most
high wind range out of your
headsail, flatten and depower your jib by
tightening the backstay, which reduces sag, and at the same time
tightening the luff tension at the tack. This will help pull
the draft forward again, and prevent the entry from becoming too
flat forward, to lock in a proper foil shape.
JIB
LEAD: The jib lead should start at
approximately 8'
6.5" measuring from the headstay at the deck level to the
center of the sheeve in the loaded position. Fuller jibs, such as
the DCL and DCM, like the foot almost taught while flatter
jibs, such as the AP 7.5, perform best with some depth in
the foot. This takes some experimenting to get right, but remember
that every time you adjust the halyard or change the halyard
length you will change the clew height, which will affect jib
sheeting angle. Your jib leads should be mounted on the deck as
close to the cuddy as possible and have room for adjustment
forward and aft of the recommended settings.
JIB
SHEET TENSION: The jib sheet should be trimmed to keep
all the telltales flying, which includes the leech telltale
that should never be stalled. To maximize pointing upwind we try
to trim the jib as tight as possible without ever stalling the
leech telltale.
Dual tabs on the jib luff is a feature
designed to both add fullness and allow for a tighter headstay in
sloppy conditions. On the long tabs the headstay can be carried
tighter and will not bounce as much in the chop. This technique
works best in the lower wind range of the headsail you are flying
when you are in need of more forward speed and power. Bare in mind
that you will lose some pointing ability because of the combination of
tighter headstay and fuller shape that is achieved with the long
tabs.
MAINSAIL
SETTINGS: For most conditions, the
mainsail should be trimmed so
that the top batten is parallel to the boom. When in either very
light air or medium to heavy air and chop, the top batten should
be twisted open a few degrees to keep the top batten leech
telltale flying at least half the time.
TRAVELER:
We like to set the traveler to fine tune the weather
helm. In all wind speeds, I like to carry zero to three lbs. of
weather helm. In light air, the traveler car can be as much as
12" above centerline, and the boom can actually be a few
inches above center line also in order to load the helm. As the
wind speed increases from 6 to 12 knots the traveler car
progressively gets closer to centerline.
As the breeze increases over 20 knots, the top batten
will become more than 5 degrees open. All this time the backstay
will have become progressively tighter. Before lowering the traveler
below centerline make sure the outhaul is fully
tensioned to the band. I don't like to carry the traveler more
than a few inches below centerline or I find I cannot sail close
enough to the wind.
CUNNINGHAM:
The cunningham
should
not be used until 15 knots or more. As the wind continues to build
and you tension the backstay more to flatten and de-power the main
the cunningham can help reposition the draft back forward in the
mainsail.
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