There are about 25 holes on each of my one-inch tracks for the Genoa Car. What's an ideal location using a 150 Genoa?
Thanks
Tom
Genoa Car Placement - CD25
Moderator: Jim Walsh
Genoa Car Placement
Tom,
As a starting point I set the car so the sheet bisects the angle at the clew. That seems to give good tension on the foot and leech. From there I adjust when needed. For example, if I notice some flutter in the leech, I'll move the car forward for more leech tension.
As a starting point I set the car so the sheet bisects the angle at the clew. That seems to give good tension on the foot and leech. From there I adjust when needed. For example, if I notice some flutter in the leech, I'll move the car forward for more leech tension.
Sail on,
Jack
CD28 Sea Belle
Hailport - Rockland, ME
There are old sailors and bold sailors, but there are no old, bold sailors.
Reef early and often. It's easier to shake out a reef when one is bored than it is to tuck one in when one is scared.
When your only tool is a hammer, all your problems look like nails.
Jack
CD28 Sea Belle
Hailport - Rockland, ME
There are old sailors and bold sailors, but there are no old, bold sailors.
Reef early and often. It's easier to shake out a reef when one is bored than it is to tuck one in when one is scared.
When your only tool is a hammer, all your problems look like nails.
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Al Levesque
- Posts: 295
- Joined: Feb 6th, '05, 09:00
- Location: Athena CD33 #94 Salem MA
If you have tell-tales along the luff you will see the effect of moving the car fore and aft. Without tell-tales look to see how high or low the luff starts to break. Set the car where the luff or the tell-tales break uniformly from top to bottom.
As you can guess, a change of relative heading means a change of car position. Anyone that dedicated gets to win the race. I set the car for the tightest heading and accept the inefficiency when off the wind.
As you can guess, a change of relative heading means a change of car position. Anyone that dedicated gets to win the race. I set the car for the tightest heading and accept the inefficiency when off the wind.
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tartansailor
- Posts: 1529
- Joined: Aug 30th, '05, 13:55
- Location: CD25, Renaissance, Milton, DE
Jib Car
My cars ride in rollers; bungee cord tensions them forward, and a line around the car's block allows me to make adjustments without leaving the cockpit.
Dick
Dick
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Rollergirl
- Posts: 87
- Joined: May 21st, '05, 14:27
- Location: Flying Scott, Sunfish
From the North Sails website:
I have included the adjacent information about halyard tension and sheeting. It's all interrelated.
Go to http://www.northsails.co.uk/articles/fast/default.htm, select the information tab, scroll to Articles and Tips. You will find Perfect Pointing in the lower left section.
"Luff tension…..
The major characteristics of genoa, or jib shape, are the amount and location of draft, and the angle of entry. The shape of the jib is controlled by the fore and aft location of the jib leads, luff tension, sheet tension and headstay tension.
Tension on the leading edge of the sail is controlled by jib halyard and by jib Cunningham. The principal effect of luff tension is to position draft in the sail. Increased luff tension moves draft forward. Reduced luff tension allows the draft to move aft. In general new sails need much less halyard than old sails as the draft is still at the sail designers desired position. In headsails the draft position is normally between 34% to 44%.
As a rule of thumb, the luff of the headsail wants to be tight enough so that it just takes the wrinkles out of the sail along the luff tape. Naturally, you'll want this to be tighter in breezier conditions and looser in lighter conditions. The headsail trimmers and the pit crew (or whoever secures the halyards) should note—mentally and in writing—the proper settings for each sail and for the conditions throughout the range of that sail.
Jib Car / Lead position…….
Most boats are now able either through purchase systems, hydraulics or jut plain simple pin stop cars to move jib sheet leads fore and aft. The position of the lead controls the tension on the leech and the foot, as well as the draft location in the upper third of the sail and has an effect on the draft in the lower third.
In simple break down terms if we move the jib cars aft we move the draft in the top of the sail forward and allow the leech to fly with more twist, consequently the foot flies with less depth.
Move the jib lead forward and this moves the draft in the top of the sail aft and moves the draft in the bottom of the sail forward. The leech flies tighter with less twist and the foot is more rounded and deeper. The correct jib lead position distributes draft evenly in the sail and the tension on the leech and foot are relatively equal.
Ascertaining the correct jib car position is greatly aided by our use of the tell tales. All we need to do is locate which portion of the sail begins to luff first. I always use tell tales on the quarter, half and three quarter heights of the sail, this gives a balanced view of the sails luff.
If the sail breaks or lifts in the upper portion means that the lead should be moved forward. If the sail breaks in the lower portion the jib car needs be moved aft.
If you're sailing with non-overlapping headsails determine your lead position by lining up marks on the spreaders with the leech of the jib. The telltale at the top batten should be used to ensure that the head of the sail is not stalled. When setting up a jib, it is important to be sure that you are looking at the entire leech of the sail, all the way up to the head. Minor adjustments of sheet tension and lead position are especially powerful on high aspect jibs. The slightest change in car position can mean big changes at the head of the sail.
It is also important to be sure that the halyard tension is correct for the existing conditions before determining the lead position. If the halyard is too soft, the leech will fly too round, causing you to drop the lead too far aft. The same is true if the halyard is too tight. You will end up with the lead too far forward in an attempt to round the back of the sail up in your search for power.
Jib Sheet
Along with controlling the angle of attack to the wind the jib sheet controls the amount of draft and twist in the jib. A tight jib sheet will remove draft from the sail; easing the sheet will add draft and twist to the sail. It is always worth remembering that the sheet is still the most powerful control and has the biggest effect on the sail.
Forestay……
The straightness of the headstay is controlled by tension on the backstay, use of running backstays, chocking or use of a ram at deck level or on some boats an adjustable headstay. The looser the headstay, the more the middle of the wire sags to leeward and astern. Increased tension reduces the depth of the headsail moves the draft forward and flattens the entry angle. Decreased tension increases the depth allows the draft to move aft and creates a rounder entry."
I've always found the most difficult part of all this is getting enough headstay tension. With many boats, the cabin mounted mast disallows the higher tensions necessary to fly a smaller sail more powerfully. Thus, we are stuck with larger headsails, more weather helm and bigger control issues.
When I had my Ty, I experimented with higher headstay tension, and it made a noticable improvement in my ability to point and sail flatter. But I could measure the cabin top deflection, and backed off after a day of experimentation.
I race on Ensigns, and the fastest boats carry very high headstay and jib halyard tensions. Of course, the Ensign has a keel mounted mast.
Good luck
Bill
my refurbished Ensign is for sale
Go to http://www.northsails.co.uk/articles/fast/default.htm, select the information tab, scroll to Articles and Tips. You will find Perfect Pointing in the lower left section.
"Luff tension…..
The major characteristics of genoa, or jib shape, are the amount and location of draft, and the angle of entry. The shape of the jib is controlled by the fore and aft location of the jib leads, luff tension, sheet tension and headstay tension.
Tension on the leading edge of the sail is controlled by jib halyard and by jib Cunningham. The principal effect of luff tension is to position draft in the sail. Increased luff tension moves draft forward. Reduced luff tension allows the draft to move aft. In general new sails need much less halyard than old sails as the draft is still at the sail designers desired position. In headsails the draft position is normally between 34% to 44%.
As a rule of thumb, the luff of the headsail wants to be tight enough so that it just takes the wrinkles out of the sail along the luff tape. Naturally, you'll want this to be tighter in breezier conditions and looser in lighter conditions. The headsail trimmers and the pit crew (or whoever secures the halyards) should note—mentally and in writing—the proper settings for each sail and for the conditions throughout the range of that sail.
Jib Car / Lead position…….
Most boats are now able either through purchase systems, hydraulics or jut plain simple pin stop cars to move jib sheet leads fore and aft. The position of the lead controls the tension on the leech and the foot, as well as the draft location in the upper third of the sail and has an effect on the draft in the lower third.
In simple break down terms if we move the jib cars aft we move the draft in the top of the sail forward and allow the leech to fly with more twist, consequently the foot flies with less depth.
Move the jib lead forward and this moves the draft in the top of the sail aft and moves the draft in the bottom of the sail forward. The leech flies tighter with less twist and the foot is more rounded and deeper. The correct jib lead position distributes draft evenly in the sail and the tension on the leech and foot are relatively equal.
Ascertaining the correct jib car position is greatly aided by our use of the tell tales. All we need to do is locate which portion of the sail begins to luff first. I always use tell tales on the quarter, half and three quarter heights of the sail, this gives a balanced view of the sails luff.
If the sail breaks or lifts in the upper portion means that the lead should be moved forward. If the sail breaks in the lower portion the jib car needs be moved aft.
If you're sailing with non-overlapping headsails determine your lead position by lining up marks on the spreaders with the leech of the jib. The telltale at the top batten should be used to ensure that the head of the sail is not stalled. When setting up a jib, it is important to be sure that you are looking at the entire leech of the sail, all the way up to the head. Minor adjustments of sheet tension and lead position are especially powerful on high aspect jibs. The slightest change in car position can mean big changes at the head of the sail.
It is also important to be sure that the halyard tension is correct for the existing conditions before determining the lead position. If the halyard is too soft, the leech will fly too round, causing you to drop the lead too far aft. The same is true if the halyard is too tight. You will end up with the lead too far forward in an attempt to round the back of the sail up in your search for power.
Jib Sheet
Along with controlling the angle of attack to the wind the jib sheet controls the amount of draft and twist in the jib. A tight jib sheet will remove draft from the sail; easing the sheet will add draft and twist to the sail. It is always worth remembering that the sheet is still the most powerful control and has the biggest effect on the sail.
Forestay……
The straightness of the headstay is controlled by tension on the backstay, use of running backstays, chocking or use of a ram at deck level or on some boats an adjustable headstay. The looser the headstay, the more the middle of the wire sags to leeward and astern. Increased tension reduces the depth of the headsail moves the draft forward and flattens the entry angle. Decreased tension increases the depth allows the draft to move aft and creates a rounder entry."
I've always found the most difficult part of all this is getting enough headstay tension. With many boats, the cabin mounted mast disallows the higher tensions necessary to fly a smaller sail more powerfully. Thus, we are stuck with larger headsails, more weather helm and bigger control issues.
When I had my Ty, I experimented with higher headstay tension, and it made a noticable improvement in my ability to point and sail flatter. But I could measure the cabin top deflection, and backed off after a day of experimentation.
I race on Ensigns, and the fastest boats carry very high headstay and jib halyard tensions. Of course, the Ensign has a keel mounted mast.
Good luck
Bill
my refurbished Ensign is for sale
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Carl Thunberg
- Posts: 1307
- Joined: Nov 21st, '05, 08:20
- Location: CD28 Cruiser "Loon" Poorhouse Cove, ME
Dick, any photos?
I'm intrigued by your setup, but I'm having trouble visualizing it. Moving my cars is a bit of a production, so I tend not to use them as much as I know I should.
CDSOA Commodore - Member No. 725
"The more I expand the island of my knowledge, the more I expand the shoreline of my wonder"
Sir Isaac Newton
"The more I expand the island of my knowledge, the more I expand the shoreline of my wonder"
Sir Isaac Newton
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tartansailor
- Posts: 1529
- Joined: Aug 30th, '05, 13:55
- Location: CD25, Renaissance, Milton, DE
Ball Bearing Adjustable Lead Cars
Hi Carl,
Digital is down. I have Lewmars, but they are devoid of part #s.
If you refer to HARKEN part # 3072 on page 139 of their 2006 catalog, you will find a pic which should be pretty much self explanatory.
The bungee cord keeps the car from wandering under no load, for under load the car really wants to move foreword.
I have the wide sheaves, but have yet to use 2 sheets.
I hope this helps.
Dick
Digital is down. I have Lewmars, but they are devoid of part #s.
If you refer to HARKEN part # 3072 on page 139 of their 2006 catalog, you will find a pic which should be pretty much self explanatory.
The bungee cord keeps the car from wandering under no load, for under load the car really wants to move foreword.
I have the wide sheaves, but have yet to use 2 sheets.
I hope this helps.
Dick