Jib Advise

May 17, 2004
2,099
Other Catalina 30 Tucson, AZ
A sailor recently asked me to teach him how to use the jib --over the phone!! I wanted to ask him if he could teach me to play the piano over the phone.

I've found that a lot of sailors treat the jib as a secondary devise and focus mainly on the mainsail. Due to their lack of knowledge about both sails they end up with both sails working against each other. Secondly, they don't understand what elements they're adjusting on both sails and additionally what sail controls for each sail (there are 8 for the mainsail and 6 for the jib) are used to adjust each element.

The first thing I determined was his size/type of jib -- 135, roller furling - and what jib sail trim controls he had -- he had all of them -- and most importantly if they ALL function. You'd be surprised how many don't function and he had never used his fairleads..

I started with telltales, which he didn't have. I don't know how sailors trim their sails without telltales!! I explained placement is on the package.

Next I explained the halyard, which is the simplest to understand but I really don't like to use - I prefer a jib cunningham. In light winds I suggested he ease it a bit until some scollop's appear on the luff. As the wind builds, remove the scollop's. After I explained draft position I told him what is happening to the sail when you ease/tighten the halyard. Try explaining draft position over the phone!! Actually, it's pretty easy - cup your hand and draw an imaginary line down the palm. If the line is moved forward you're powering up the sail. The sail de powers when the line moves back. The sweet spot is in the middle.

There is such a thing as providing TOO MUCH info to a sailor (or anyone) at one time so I decided to limit the conversation and merely explained the importance the jib fairleads and suggested he get them to function.

Turns out he lives in Northern Maine and won't be putting his boat in the water any time soon. I suggested that in the meantime he purchase my book & chart. Then sit by the fire and keep warm while reading it to learn about ALL the sail trim control for the main and jib and how/why they function and most importantly WHAT they're adjusting. The WHY/WHAT of sail trim is EVERYTHING otherwise a sailor is just guessing at the adjustment.

You never know how much info a sailor absorbs from any conversation but 3 days later I received his check for both products.
 
Feb 26, 2004
22,760
Catalina 34 224 Maple Bay, BC, Canada
You never know how much info a sailor absorbs from any conversation but 3 days later I received his check for both products.
Best money the guy ever spent on his boat, and his mind. :)

Don's been around here for a loong time, thank goodness.

His book is the very best I've ever read about the subject.

Well worth the modest expense to learn how to make your SAILboat work! :)
 
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Slick

.
Jun 17, 2016
13
Ericson 35 3 Paris Landing Tn
I just bought my 2nd and third charts. The first set blew over the side.
As a new sailor the amount of information
is a little overwhelming if I try to take it all in at once. I find it very helpful and so bought a spare set.
I have a habit of moving things too far when I adjust, especially the fairleads.
Do you think it's worthwhile for a cruiser to replace the slides that lock in a hole with the ones that are adjustable by pulling a line?
Thanks for sharing your knowledge.
 
Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
Slick.. I think you need to put a leash on your charts and tie it into the cockpit.
I have lost count on how many of my favorite hats have sailed out into the water never to be recovered. I now tie them to my shirt collar.

To your question. The adjustable jib cars are a nice addition to a boat. If you race your boat it makes it very easy to "tweak" the sail shape to get that extra burst of speed to sail past your competition. Of course they also have the same tool so they see what you are doing and try to match it and the batter is on.

As a cruiser, I make those adjustments with my antique pin jib car. It eventually becomes a natural step in preparing your boat. You choose the sail before you go sailing. You can set the car for most of the days needs. If you're going to be beating into the wind you'll likely want the car in the back (toward the stern) position. My method is to set it where I think it needs to be and take a tack. If I do not like the sail shape, I adjust the windward car to a new position and tack. If that is looking good I set the other car to the same position and off we go. Two cars are both good to go. If I am going to head down wind I move the car towards the bow. using the same technique.

One of the differences between racing and cruising is the length of time you will sail on one tack. The more relaxed nature of cruising means you have plenty of time to set and leave the trim. Unless the wind plays fickle and starts moving around. Then you access the change and make the needed adjustment.

A new sailing experience means go out and play. Try a few different sets and see what happens. You will quickly gain a sense of what moves your boat. The charts will be less of a crutch as you build experience. If you decide to get into the racing circuit then you'll break out the trim guides again.

A great and fun way to learn is to take a fellow sailor out for a day and pick his/her brain about your boat and sailing.
 
Mar 26, 2011
3,400
Corsair F-24 MK I Deale, MD
Numerous times, as a 35-year experienced chemical engineer, I had people ask me where they could take a single class to learn to do what I did. I wish there was.... I missed that class, so it took longer.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Slick.. I think you need to put a leash on your charts and tie it into the cockpit.
I have lost count on how many of my favorite hats have sailed out into the water never to be recovered. I now tie them to my shirt collar.

To your question. The adjustable jib cars are a nice addition to a boat. If you race your boat it makes it very easy to "tweak" the sail shape to get that extra burst of speed to sail past your competition. Of course they also have the same tool so they see what you are doing and try to match it and the batter is on.

As a cruiser, I make those adjustments with my antique pin jib car. It eventually becomes a natural step in preparing your boat. You choose the sail before you go sailing. You can set the car for most of the days needs. If you're going to be beating into the wind you'll likely want the car in the back (toward the stern) position. My method is to set it where I think it needs to be and take a tack. If I do not like the sail shape, I adjust the windward car to a new position and tack. If that is looking good I set the other car to the same position and off we go. Two cars are both good to go. If I am going to head down wind I move the car towards the bow. using the same technique.

One of the differences between racing and cruising is the length of time you will sail on one tack. The more relaxed nature of cruising means you have plenty of time to set and leave the trim. Unless the wind plays fickle and starts moving around. Then you access the change and make the needed adjustment.

A new sailing experience means go out and play. Try a few different sets and see what happens. You will quickly gain a sense of what moves your boat. The charts will be less of a crutch as you build experience. If you decide to get into the racing circuit then you'll break out the trim guides again.

A great and fun way to learn is to take a fellow sailor out for a day and pick his/her brain about your boat and sailing.
The unovercome-able disadvantage of the pin cars that is often overlooked is the distance between the adjustment points. Remote adjustable cars are infinitely adjustable, which can make a huge difference, in particular on high-aspect jibs. Often the pins create a too-for forward, too-far aft situation.
 

jwing

.
Jun 5, 2014
503
ODay Mariner Guntersville
I have a habit of moving things too far when I adjust, especially the fairleads.
I know the challenge of trying to learn sailing with a big boat, especially in light air. The boat reacts too slowly to know what effect was made by a change in trim. When I was chartering boats, we always over-steered, because it took so long for the boats to turn. Even when we thought we were getting good, a glance at the water behind us gave the impression that we had been running a slalom course. One of the best sailing lessons that I ever got was from the first auto-pilot I ever used. Otto would make a tiny course change then wait a bit before assessing and making another tiny change. It made LOTS of tiny changes.

My recommendation is trim your sails to the telltales. They give fast feedback. I offer the caveat that if you don't control your jib sheet angle, trimming to the telltales can be an exercise in frustration management. This is what Don has already written on Post#1.

Do you think it's worthwhile for a cruiser to replace the slides that lock in a hole with the ones that are adjustable by pulling a line?
For me, it was. But my boat is much smaller than yours, so it did not cost me much to fashion such a system. And with small sails, I don't need a winch to adjust. You may be interested in this discussion:

https://forums.sailboatowners.com/index.php?threads/floating-genoa-jib-leads.195962/#post-1526605

I haven't experienced that set-up, so I cannot give guidance.
 
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May 17, 2004
2,099
Other Catalina 30 Tucson, AZ
Numerous times, as a 35-year experienced chemical engineer, I had people ask me where they could take a single class to learn to do what I did. I wish there was.... I missed that class, so it took longer.
Thinwater: I think I came close to providing a 1 day class - actually, it involved 2 days and I have the testimonials to prove it. The seminar was 4 hours, with 2 short bathroom breaks. It was like learning sail trim from a fire hose!! You learned WHAT each sail trim control for the main & jib was adjusting. Probably, 50% of the sailors worldwide have no idea what each sail trim control for the main & jib is adjusting. If you don't believe me ask that question of your sailing friends. You'll be surprised at the answers you receive. Sail Trim Forum regulars mostly know the correct answers. After I got them through the WHAT I discussed the correct sail trim adjustment and sequence for each sail trim control in each wind condition and point of sail.

Sitting in a classroom is one thing -- the real test is on can the sailor perform the functions on the water. I developed a 4 hour
"on the water" class. At the end of the 4 hours I'll match their sail trim against any beginner to intermediate sailor worldwide. Dennis Conner wasn't calling these folks for sail trim advise but each of them had a solid foundation to build on. A solid foundation is everything in whatever a person is doing.
 
Mar 26, 2011
3,400
Corsair F-24 MK I Deale, MD
^^
For a moment I though you meant 35 years of Chem E in 2 days!

Yes, those are the fundamentals:
  • How do you twist cloth into shape? There are more controls than they generally realize. The trouble is they have been given simple rules, not an understanding of HOW they change the shape.
  • How do the sails interact to form, in effect, one foil system?
  • Vertical wind twist, of course.
  • Heel control.
  • The interaction of sail balance, keel leeway, and rudder balance.
  • How and when to bend the rules to help tack, reef, jibe, or slow down.
A lot of 3 dimensional thinking.
 
Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
Most have trouble with 3 dimensional thinking. Quite a few are troubled in 2 dimensions.
Throw in time and forget.
The trouble for many is that sailing is a dynamic process not a set and forget experience. The more that time is a factor the greater your 3 dimensional environ changes.

2 days - 4 hours.... must have been brilliant.
 
Aug 2, 2010
502
J-Boat J/88 Cobourg
We are working to get our boat up to speed and having some gentle disagreements about sail trim including jib car placement. We have in-haulers and a good guide as to where to put them but having the car anywhere but absolutely at the back makes him crazy as he thinks we are getting too much drag and we don't need power. What effect will having the cars too far back have on pointing and speed if the sail trims smooth and flat?
I found her feeling dead last night in 12 knots of breeze though we weren't too far off polars.
 
May 17, 2004
5,028
Beneteau Oceanis 37 Havre de Grace
We are working to get our boat up to speed and having some gentle disagreements about sail trim including jib car placement. We have in-haulers and a good guide as to where to put them but having the car anywhere but absolutely at the back makes him crazy as he thinks we are getting too much drag and we don't need power. What effect will having the cars too far back have on pointing and speed if the sail trims smooth and flat?
I found her feeling dead last night in 12 knots of breeze though we weren't too far off polars.
If the boat isn’t overpowered and the top is too twisted off then the way I see it you’re just leaving money on the table. First thing though is to figure out if the top is too twisted off, especially since you said the sail is smooth. Is the top Windward telltale lifting before the bottom one? Does the top visibly luff early? If not then the sail could be trimmed right and just need the car that far back based on how it’s cut and where the tracks are. If you decide there is too much twist then next is to figure out if you’re overpowered. How much helm is there? Are you needing to feather the main to keep flat? If not then I’d go for more power if you can get it. In 12 knots my guess is that’s pretty borderline. At low wind speeds you’re going to need extra twist because the wind is so much faster up high. At moderate wind speeds is when you can cut down the twist, but as you get too much power, probably somewhere around 12, twist should go up again.
 
May 17, 2004
2,099
Other Catalina 30 Tucson, AZ
We are working to get our boat up to speed and having some gentle disagreements about sail trim including jib car placement. We have in-haulers and a good guide as to where to put them but having the car anywhere but absolutely at the back makes him crazy as he thinks we are getting too much drag and we don't need power. What effect will having the cars too far back have on pointing and speed if the sail trims smooth and flat?
I found her feeling dead last night in 12 knots of breeze though we weren't too far off polars.
Danstanford: I assume you have telltails? The combination of reading both your telltails and the sail will give you the proper car placement. The first thing to understand is how the leads function relative to forward and back placement. Head into the wind and watch the luff. If the foot flutters, bottom luffs or bottom telltails break first - move the leads aft. If the leech flutters, top luffs or the top telltail breaks first - move the lead forward. How far forward or back should you move the leads - I have no idea but you want the telltails and sail to break evenly from top to bottom and I'll bet with the cars all the way back that ain't happening. Your telltails must be telling you something is wrong. All the way back may be "right" for a certain wind condition but it's "wrong" for all others plus if it was always right why would you need a track?

It's the job of the jib trimmers to read the break of the sail and communicate with each other. Let's say you're sailing in medium wind and all telltails are streaming with the windward telltails jumping every few seconds. That's a good set up but unfortunately the wind is always changing and it might be different on the new tack. So as the jib trimmer is releasing the sheet slowly going into the tack he's watching the break of the jib and he has to be quick about his "read" because it happens quickly but after they do it a few times it's easy to see. Let's say he sees the foot flutter and bottom telltail break. He tells his trimmer partner to move his car back a bit. If it's a big break he tells him to move it a lot. How much is "a bit" and "a lot" - I don't know as you have to experiment. The track isn't 50' long so you're only dealing in inches or small adjustments. If the break is even top to bottom the lazy trimmer doesn't move his car.

Since I have a C30 masthead rig and the jib is the engine the leads are the primary sail trim control -- they adjust EVERYTHING. The first mod I made was replacing the pin type leads with the Garhauer adjustable lead system and I further rigged it so I could adjust the leads both forward and backward to allow for fine tuning. Jib trimming is a hard job and it's why I never did it - I liked the traveler. All i had to do was react to what the set because you want the main and jib set to match. The jib trimmer on a masthead rig will make or break the boat.

Don't know if I helped you or other sailors reading this topic.
 
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Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
Don and David have both given you great responses to the challenge of setting the jib car. Many racing running rigging on boats have jib cars that move like a traveler. It gives infinite adjustment options within the length of the track.

Thinking like a cruiser/sailor.

When the jibcar is back near the cockpit, as I pull in on the sheet the angle of the sheet is pulling the foot of the sail tight. The sheet is almost in line with the foot of the sail. The leach of the sail is less affected. Looking up at the sail I can see the top half of the leach open (twisted off), spilling the upper wind. There is a real large curve between the Main and the Jib.

When I move the jibcar to the bow end of the track, pulling in on the sheet affects the leach of the sail. It gets pulled down as the angle of the sheet from the end of the sail is almost in line with the sail leach. The shape of the leach is almost a straight line following the main. There is nearly no curve between the jib leach and the Main sail. I call it closed.

Now if you have your "In Haulers" (some times referred to as Tweakers) out you can modify these two basic sets by adjusting how you much you pull in on the "in hauler" and where you set the "In hauler" along the sheet (in front of the jib car).

Follow Don's insights as you tweak (trim) your sail in response to the wind and the signals from the tell tails.
 
Aug 2, 2010
502
J-Boat J/88 Cobourg
It's the job of the jib trimmers to read the break of the sail and communicate with each other. Let's say you're sailing in medium wind and all telltails are streaming with the windward telltails jumping every few seconds. That's a good set up but unfortunately the wind is always changing and it might be different on the new tack. So as the jib trimmer is releasing the sheet slowly going into the tack he's watching the break of the jib and he has to be quick about his "read" because it happens quickly but after they do it a few times it's easy to see. Let's say he sees the foot flutter and bottom telltail break. He tells his trimmer partner to move his car back a bit. If it's a big break he tells him to move it a lot. How much is "a bit" and "a lot" - I don't know as you have to experiment. The track isn't 50' long so you're only dealing in inches or small adjustments. If the break is even top to bottom the lazy trimmer doesn't move his car.
^^^ This is gold Don, I am going to share this with our Guys as a guideline for them to do this without upsetting what others are doing by asking for a course change. Not sure why this never occurred to me but it is a great way to make the trimmer(s) have awareness and tools to do the job right.
 
Aug 2, 2010
502
J-Boat J/88 Cobourg
Don and David have both given you great responses to the challenge of setting the jib car. Many racing running rigging on boats have jib cars that move like a traveler. It gives infinite adjustment options within the length of the track.

Thinking like a cruiser/sailor.

When the jibcar is back near the cockpit, as I pull in on the sheet the angle of the sheet is pulling the foot of the sail tight. The sheet is almost in line with the foot of the sail. The leach of the sail is less affected. Looking up at the sail I can see the top half of the leach open (twisted off), spilling the upper wind. There is a real large curve between the Main and the Jib.

When I move the jibcar to the bow end of the track, pulling in on the sheet affects the leach of the sail. It gets pulled down as the angle of the sheet from the end of the sail is almost in line with the sail leach. The shape of the leach is almost a straight line following the main. There is nearly no curve between the jib leach and the Main sail. I call it closed.

Now if you have your "In Haulers" (some times referred to as Tweakers) out you can modify these two basic sets by adjusting how you much you pull in on the "in hauler" and where you set the "In hauler" along the sheet (in front of the jib car).

Follow Don's insights as you tweak (trim) your sail in response to the wind and the signals from the tell tails.
We do have in-haulers and they really give a rounded foot to the jib when activated so the response has been to offset this by moving the car back and sheeting on harder till it "looks right" which is all the way back on the track.
I think I have another challenge somewhere in the setup as I have no weather helm at all and we are not pointing as high as I think we should be despite the fact that I already have the forestay set about an inch longer than what is recommended in the tuning guide.
We will keep on tweaking for sure.
 
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May 17, 2004
2,099
Other Catalina 30 Tucson, AZ
We do have in-haulers and they really give a rounded foot to the jib when activated so the response has been to offset this by moving the car back and sheeting on harder till it "looks right" which is all the way back on the track.
I think I have another challenge somewhere in the setup as I have no weather helm at all and we are not pointing as high as I think we should be despite the fact that I already have the forestay set about an inch longer than what is recommended in the tuning guide.
We will keep on tweaking for sure.
I'm not sure of this but your lack of weather helm might be a result of the position of your forestay. You might be experiencing lee helm.

There's pinching, pointing, footing, acceleration and full speed. Your telltails will indicate which mode your in or approaching. I show diagrams of each mode on my SAIL TRIM CHART. In other words, you went past pointing and are now into the pinching mode or you're going out of pointing into footing. Most boats have a limitation as to how high they can go, which you have to determine. Once you reach the max position you can hope all you want but you "ain't" going any higher.

To obtain 100% efficiency both the main and jib must be trimmed perfectly for the point of sail and wind conditions. This is not easy to accomplish. It takes a lot of work to get there and 60% of the sailors worldwide never get there and that's no problem because a day on the water is better than a day on land. If the boat is not trimmed to 100% it will still move through the water but the sails/boat are not as happy as they'd like to be. A group of the sailing population just want to raise the sails and move through the water and again that's fine. If a sailor wants to move toward 100% efficiency they must be prepared to put some (a lot) of work/effort into it and the sailor must learn what the sails/telltails are telling him.

All it takes is ONE person on the boat that understands what he's doing - like a manager. Without a manager you have chaos. Here's an example. When I first got into sail trim I felt that being on a race boat was the way to learn. I contacted the top skippers but no one would take me - sort of like asking the most popular/attractive girl to the prom and she tells you she'll call you. Anyway, finally I found a pick crew adv at West Marine. Problem was no one knew what they were doing including the skipper. Some times when we crossed the finish line the race crew had gone home!! One timed I tracked the course we sailed. We sailed 4 miles father than necessary!! The final straw was a race out of Long Beach. You sail out and around a a fixed marker. Didn't know it at the time but it shoals up around the marker. I mentioned to the skipper that all the boat in front are turning wide. He was flying his new spin and felt he was catching them. Anyway, we turn the mark and the next thing I noticed is we're heeled WAY over and I'm looking directly into the water. The boat comes up and then goes over again - even farther. Finally, the spin rips. That sound was music to my ears. I never sailed with them again. I didn't learn a thing from that boat. I didn't even learn what not to do because I didn't know "what not to do" was!!