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Tuning and Sail TrimPaul Abdullah
Tuning and Sail Trim
Topics1.Rig Tips 2. Mainsail Trim
3. Headsail Trim 4. Spinnaker Trim
Rig Tuning
Rig Tuning – Important points
All Boats are different, but here’s some common areas to focus on:
► 1. Mast Centering
► 2. Mast Rake
► 3. Butt (Base) Position
► 4. Pre-Bend
► 5. Side-to-side
► 6. Bendiness
Rig Tuning – Centering the Mast
► 1. Measure from point A to B and divide in half to find the center of the boat, position center of mast to that point
► 2. Swing jib halyard from point A to B and make sure they are the same length, this will ensure the hounds are in the center of the boat
Rig Tuning - Rake
►Rake affects the center of effort/center of resistance (HELM!)
►Max rake increases weather helm to balance the boat
Rig Tuning – Mast Butt Position
►Moving the mast aft to its’ correct setting will induce pre-bend.
►Most One-Designs have the mast butt location in the Tuning Guide.
Rig Tuning – Pre Bend
►What is Pre-bend?
The “natural” bend where the mast is tuned
► Important to set pre-bend because sailmakers build sails to a measurable pre-bend setting
Rig Tuning – Pre Bend
Rig Tuning – Side to Side
► To check side bend sight up the back of the mast
► If the lowers are too loose the tip will poke to weather and the middle will sag to leeward
► If the lowers are too tight the tip will fall off to leeward and the middle will poke to weather
► 1. In heavy air poke to weather in the middle of the mast will depower the mainsail by opening up the upper leech
► 2. A straight mast fits the designed shape of the sail for most conditions
► 3. In light air sag to leeward in the middle of the mast will power up the main by firming up the leech
Rig Tuning – Lower Tension
Rig Tuning – Mast Bend
► 1. Draft position moves aft as the mast bends
► 2. Cunningham tension moves the draft forward
Rig Tuning – Mast Bend
Lots of prebend Little prebend
Rig Tuning
So…..What’s Important???
1) Mast – Centered in the boat
2) Mast – Rake set to balance boat
3) Develop a PERSONAL TUNING GUIDE
4) Bend – To match sails (Prebend)
5) Sight up the mast/main track
a) At the dock
b) On the water in 10 knots
Mainsail Trim
Mainsail Trim – Mechanisms
1) GEAR CHANGES = Speed
2) Mainsheet
3) Traveler
4) Controls
-Vang
-Cunningham
-Outhaul
-Backstay
Mainsail Trim
► Easing the mainsheet opens the leech and decrease weather helm, making the boat easier to sail straight – I.E. 1st Gear
►Oversheeting the mainsheet will close the leech, increasing weather helm and making the bow want to point up – I.E. 3rd Gear
Mainsail Trim Eased Look
1st Gear – Top Batten Open
*Accelerate!
Mainsail Trim Overtrimmed Look
3rd Gear – Top Batten Closed
*Point Mode
Mainsail Trim – 3 Gears!
3rd Gear
2nd Gear1st Gear
Mainsail Trim - Traveler
► 1. The traveler changes power in the mainsail by changing the angle to the wind
► 2. The traveler will also affect
pointing ability
► 3. No Traveler? VANG SHEET!!Laser, new vang
Snipe
Thistle
Mainsail Trim - Traveler
Mainsail Trim - Vang
► 1. Vang affects lower mast bend and leech tension
► 2. A tight vang allows you to ease the mainsheet without losing leech tension
►DO YOU HAVE DECK STEPPED MAST –or- KEEL STEPPED MAST
Mainsail Trim - Controls
► Cunningham
Affects the draft position
Mainsail- Over-Bend Wrinkles
Mainsail Trim
TWIST vs. HOOK
Draft Forward – Big Twist Draft Middle – Perfect Trim
Mainsail Trim - Outhaul
► 1. A loose outhaul makes the bottom of the main fuller for more power
► 2. A tight outhaul flattens the bottom of the sail and opens the lower leech
Mainsail Trim
Loose Outhaul
Closes Slot
Slot Management
Mainsail Trim – Using theTelltail
► 1.The mainsail is overtrimmed when the telltale curls to leeward
► 2. Slight overtrim on the main puts the boat into point mode
Mainsail Trim
Use the top telltail as a
Trim Guide only
Flowing
Stalled
Twist vs. Hook
►Twist is used
To INCREASE FLOW
►To gain speed out of a tack
►To accelerate out of tacks (but sacrifices height)
►To “bleed” pressure
►Hook is used
To DECREASE FLOW
►Captures more airIncreases Helm
Increases Point (but slows you down)
Mainsail Trim
So…..What’s Important???
1) Know the boat’s GEARS
2) Communicate with helmsman
3) Set & Mark your controls
a) Vang
b) Cunningham
c) Outhaul
4) Use your reference points
a) Telltails
b) Trim points (corner of boat)
Headsail Trim
Headsail Trim – Lead Placement
► 1. Low aspect headsails sheet at an angle nearly bisecting the leech and foot
► 2. High aspect sails sheet more directly up the leech
► 3. Moving the lead forward will close the leech for power, moving it aft will open the leech to depower
Headsail Trim - Reference
►Mark your Spreaders
►Gives trimmers visual reference
►Gives trimmers/helmsman verbal reference
► Place marks to correlate with the “GEARS” for your particular boat
Trim Guides
Mark your spreaders!!! Establish Communication
Establish Communcation!!!
Driver
Genoa Trimmer
Main Trimmer
Headsail Trim – Luff Sag
►Headstay sag increases depth in the headsail to add power
► Sag controls sail entry, deep for chop, fine for flat water
Headsail Trim – Luff Sag
► Sag can be controlled through backstay and shroud tension
Headsail Trim – Telltail Flow
► Proper trim allows the wind to flow evenly on both sides of the sail, telltales flow aft
►Overtrimming stalls the windflow on the backside of the sail, creating vortices that spin the telltale
Headsail Trim
So…..What’s Important???
1) Know the boat’s GEARS
2) COMMUNICATE with helmsman
a) Where are you trimmed?
3) Set & Mark your controls
a) Backstay
b) Lead Position
c) Halyard tension
4) Use your reference points
a) Spreader Marks
Spinnaker Trim
Spinnaker Trim
► What are the two fool-proof rules-of-thumb in judging pole height?
► ENDS
► CENTER SEAM
Spinnaker Trim
Even Clews
Center Seam in
line with the
mast
Spinnaker Trim – Pole height
Reaching
► 1. Pole too high flattens the luff and moves the draft aft, closing the leech
► 2. Lowering the pole moves the draft forward and opens the leech
►CONTROLS ENTRY/EXIT
Spinnaker Trim
►As a rule, the spinnaker pole should be square to the wind
Downwind Mainsail Trim
► 1. Too little vang allows too much twist and flattens the top of the main, depowering the sail
► 2. Vang on decreases twist and makes the top of the main deeper and more powerful
Downwind Trim – Main Twist
PERFECT! TOO
MUCH
TWIST!
Downwind Trim – Perfect twist
Top Batten
Parallel to boom
Watch TelltailMake sure it is not
Stalled!!!
Twist in Main - Downwind
Vang on
Please!
Spinnaker Trim
So…..What’s Important???
1) Pole Height & Effects
2) Pole Position to the wind
3) Watch your signs
a) Clew height
b) Center Seam
4) Work the curl!
5) Communicate with driver
Spin Trim- Perfect Balance!