Association Forum - Reducing the Jib.

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

General Sailing Forum

Reducing the Jib.

New Topic

Topic Locked

Printer Friendly

Author

Topic

sodonnell
1st Mate

Member Avatar

76 Posts

Initially Posted - 08/01/2005 : 00:36:57

I've been having alot of problems with weatherhelm on my day trips.
Two time in moderate wind (10-12) the boat just rounded up.
I know I'm a novice at best in setting my sails properly but in the meantime I was wondering if it is ok/advisable to reduce the size of the jib by partially pulling it in on the furler.

Does this cause any undo stress on the system?

Edited by - on

Arlyn Stewart
Master Marine Consultant

Members Avatar

USA
2984 Posts

Response Posted - 08/01/2005 : 07:40:11

A full answer to your question depends upon more information. Which boat do you have, C25 or 250? What headsail is in use.

Roundups should not be happening in 10-12 winds... and give cause to wonder about the effectiveness of the rudder or other issues. What boat and what rudder will help in answering your question.

Edited by - on

dhunt
1st Mate

Members Avatar

USA
83 Posts

Response Posted - 08/01/2005 : 07:58:47

Furl away! . . . depending on the type/age of the furler on your boat, the size of sail you're flying, and the amount of wind you find yourself in, you may have to partially luff the sail to get the furler to work. They are designed to allow you to reduce sail when needed.

That said - 12 knots is a very pleasant amount of wind and should not cause excessive weather helm.

Visualize your boat from the side view with the wind at your back, pushing the boat away form you . . . the underwater parts RESISTS being blown downwind. Somewhere along the length of your boat, there is a point called the CENTER OF LATERAL RESISTANCE. If a steady wind blows across your boat, it will slowly turn around this point until it is parallel to the wind. If you have a swing keel that is not fully lowered, you CLR will be further aft and the boat will turn parallel to the wind more quickly.

The parts of your boat above the water are being pushed by the wind. If there is more surface area in front of the CLR then that CENTER OF EFFORT will cause the boat to turn stern first to the wind. The CE of the boat is established by the size and trim of the sails you are using and by the position of the mast as determined by design and by the 'tuning' of the rig (rake of the mast').

The objective is to keep the CE / CLR in relative balance with just a little weather helm (so the boat will turn up into the wind and stop if the helm is left unattended) A well tuned boat will have an increasing amount of weather helm as the wind builds . . . at some point the heeling and wather helm become unconfortable (usually for our passengers and crew well before ourselves) and reducing sail is appropriate.

BE AWARE that a larger headsail, properly trimmed, doesn't move the CE as far forward as you might think . . . that's because the increased velocity of the wind flowing through the slot between the main and jib/genoa adds a great deal of power to the main.

My best advice is:
1. expect a little weather helm, your boat SHOULD round up if the helm is unattended
2. when in doubt ease your sheets . . . most new sailors overtrim the sails . . .ease the main till it luffs, then ease the genoa till it luffs, then ease the main again.
3. if you are overpowered (the boat heels excessively and weather helm increases dramatically, reduce sail . . . the easiest and fastest way is to furl your foresail somewhat.
4. really efficient sailing involves balancing the amount of jib/genoa and the rake of the mast to get the most out of the boat
5. the key to really enjoying yourself and making your guests comfortable is to learn to furl your jib, and reef your main so that you are never 'overpowered' and then developing the habit of always reducing sail BEFORE you NEED to.
6. Find a seasoned sailor to go out with you and show you the ropes - we all like to sail other peoples boats!

Welcome to the forum!

Edited by - on

Bruce Baker
Captain

Members Avatar

USA
402 Posts

Response Posted - 08/01/2005 : 09:06:51

I agree with all that's been said before, but would add one additional comment. When you're overpowered, the first thing you should do is drop your traveller down to leeward. You might also flatten your sails by pulling on on the outhaul and by moving your jib cars back. That's my two cents worth.

Edited by - on

sodonnell
1st Mate

Members Avatar

76 Posts

Response Posted - 08/01/2005 : 09:50:04

Thanks for the input from all.

So, in general, can I just use a method of easing the sails out until they luff and then bring them in just enough to get moving?

I'm starting to think that I'm over trimming. As I look around me, most of the sailboats passing by are not heeled over the way I am.
And they are moving as fast as I am without fighting the tiller. (Or so it seems.)

I guess maybe it's because my early sailing experience was racing on a J22, and we were always trimmed tight and climbing to the high side.

Edited by - on

Oscar
Master Marine Consultant

Members Avatar

USA
2030 Posts

Response Posted - 08/01/2005 : 11:03:55

dhunt's remarks are right on, with the caveat that furling the jib has it's limitations. You can reduce the jib by about 20-25% before it starts loosing its shape and becomes inefficient. So a 135 down to 100, or 110 down to 85-90......

Sounds like you might benefit from buying a local experienced racer or cruiser lunch and having him or her come for a sail and give your boat a feel (your old racing skipper maybe?)......Or just look around the docks and see if there is someone who seems to have their "stuff" together.

If you can't find any volunteers contact the local sailing school.....where are you located?

Edited by - Oscar on 08/01/2005 11:12:34

sodonnell
1st Mate

Members Avatar

76 Posts

Response Posted - 08/01/2005 : 16:01:51

Long Island NY.

Edited by - on

Dave Bristle
Master Marine Consultant

Members Avatar

Djibouti
10005 Posts

Response Posted - 08/04/2005 : 22:57:02

As mentioned above, a little weather helm is desirable. "Rounding up" is generally a result of excessive heeling that causes the rudder to lose its bite, and therefore the natural "weather helm" causes the boat to swing uncontrollably into the wind. C-250s are more prone to this because of their greater beam, especially aft where the beam will raise the rudder out of the water. The broader aft area also causes the hull shift the "angle of attack" of the keel to windward as the boat heels--it sort of leans down on the leeward side of the bow. Thus, weather helm increases with the heel angle. Arlyn was asking about your boat because (1) the 250 has different characteristics from the 25, and (2) there are several rudders that have been made for the 250, mostly trying to deal with this issue.

Your suspicions about over-trimming are probably right on. Most cruising rigs and sails are not meant to be trimmed too tightly--the sails can't be flattened as they are on racing rigs with bent masts, big travelers, and performance sails. My C-25 is faster on a reach with the sails eased and the boat more upright--I don't think that she cares much which side I sit on, since she's about 5500 lbs. and not very beamy. From all that people have said here over the years, the C-250 is more sensitive to being sailed upright--either by reefing or by easing sheets (or both).

BTW, an easy way to communicate the details about your boat in each post is to put them in your "signature" which you can set up in your "profile" (the link at the top of the page). Notice that mine tells you more than you probably want to know...

Edited by - Dave Bristle on 08/04/2005 23:18:20

Brooke Willson
Admiral

Members Avatar

USA
983 Posts

Response Posted - 08/05/2005 : 07:07:50

I agree with Dave that you're probably over-trimmed. That being said, reducing the jib would tend to INCREASE weather helm, not reduce it. All other things being equal, too much jib would increase lee helm, too much main increase weather helm. When the trim is balanced between jib and main, you should have neutral or, as most prefer, slight weather helm. The feel of the tiller is a key to your sail trim; the push/pull effect of the sails is also how people can steer with the sails if they break the rudder.

My observation (and personal experience) is that beginning sailors tend to overtrim, their theory being that the tighter they pull the line, the faster the boat will go. It just ain't so. You might want to put telltales on both jib and main so you can see where the sails need to be trimmed for maximum efficiency. You'll be amazed at how much faster the boat sails upright and with the sails eased!

Brooke

Edited by - on

aeckhart
Master Marine Consultant

Members Avatar

USA
1709 Posts

Response Posted - 08/05/2005 : 13:18:36

My order of precedence to counter excessive rounding up is:

1. release the mainsheet traveler, then
2. flatten the main with cunningham and outhaul, then
3. reduce main to first reef, then
4. reduce jib from 135 to approximately 100 to 110, then
5. reduce main to second reef, then
6. reduce jib to less than 100, then
7. head home, I'm in over my head (30+ mph)

Edited by - on

Steve Milby
Past Commodore

Members Avatar

USA
5937 Posts

Response Posted - 08/05/2005 : 14:53:52

Novices who are overpowered usually undertrim their sails. Experienced sailors who are overpowered are usually carrying too much sail area. That's because novices are usually afraid to trim their sails in really flat, so their sails remain too full and thus too powerful. Coincidentally, novices also don't know how or when to reduce sail area, so their sails are not only too full and too powerful, but there's also too much sail area for the windstrength.

The reason why novices are afraid to trim their sails in really flat is because the boat often heels excessively when they do so, but the reason why the boat is heeling excessively is because they have too much sail area up for the windstrength, not because they are "overtrimming" the sails.

When you're beating to windward, the correct way to trim your sails is to trim them increasingly flatter and to move the pockets of the sails increasingly forward as the wind strength increases and as you point closer to the wind. If your sails are trimmed really flat, and the boat is still overpowered (heeling excessively and laboring) then that is a sign that you need to reduce sail area (reef the main and roll up part of the jib).

The conventional wisdom is that you should generally trim your sails flatter when beating to windward, and you should ease the controls, giving them a fuller shape, when sailing off the wind. That's ok as a general rule, but I think the better rule is, whenever you're sailing on any course from a beam reach forward, you should trim your sails flatter when you are becoming overpowered (even if you are sailing on a beam reach, for example), and trim them fuller when that condition abates. Flattening the shape of the sails de-powers them, and fullness powers them up. If you're sailing on a beam reach and are overpowered, you should flatten the sails to de-power them. If your boat is overpowered, you need to power down your sails. If your boat is not overpowered, then that means you can add more power to the sails by giving them a fuller shape. The full or flat shape of your sails is dictated more by whether the boat is overpowered or not, rather than by the course the boat is sailing relative to the wind.

Edited by - on

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.