JIB-HEADED KETCH RIG

[Torleif]

Hello!

I'm the owner of CS 17 nr. 72. My name is Torleif Holm and I live in Trondheim , Norway. It has been useful and inspiring to follow the activity on this forum. Now I decide that I dare to write something myself in my norwegian-english. I have had a lot of fun with my boat, and I really like its combination of simplicity and good performance. However , the Trondheim fjord can offer some really demanding conditions and I have been knocked down two times by catabatic gusts. The first time I got out on the CB quick enough to prevent the boat from turning uppside down. The second time I was abit slower...

With good help from a yacht and two brave kayakers it all ended well. I already knew that my seat lockers weren't water tight, and now I learned that my deck hatches weren't either. The main- mast and sail sank. The mizzen mast slipped the mast step and cracked the thwart as I turned the boat right. The security aspects and the economical aspects of this events inspire me to make an experiment: I want to try a jib-headed ketch rig with a smaller mizzen placed close to the aft deck. I will try a jib on a balanced jib boom.(Simular to swallowboats Storm 17.) For this rig I will fit a mast rail on my remaining mast, and place it in the "reefed mast hole". The mizzen is going to bee my new main sail and the other two I cut down to their right sizes from some old sails I have at home. I hope that it will work well to sail the boat with only jib and mizzen in strong winds. Is there anybody who has ideas about how to make this rig well balanced?

Finally I'm thinking of building a box on the keel plank, alongside the CB trunk, where I can add some lead ballast. Is this a good idea? If it is, what kind of problems should I bee aware of when I do this operation?

Torleif

[Dave R1]

Torleif, I won't be able to help you regarding the application of ballast to our boat. I just wanted to you have a beautiful place to sail although I can imagine it is challenging at times.

I've only been to Trondheim once--in 2000 via M/V Kong Harald, the Coastal Steamer. I'm sure I only saw a very small part of Trondheim but it left an ipressionand I want to return some day.

Good luck with getting your question answered and your sailing.

Ha det bra.

Dave Richards

I'm only Norwegian by marriage.

[Designer]

Hi Torlief,

I am sorry to to hear of your capsizes, especially with your cold water. So far I have never felt threatened by a capsize in a CS20 or CS17 but I always have the mainsheet close at hand which I have dumped many times to prevent a capsize. I did capsize a Bay River Skiff one time when someone else had control of the mainsheet and I vowed that I would never give up control of the main again.

I have no doubt that you could make a jib headed ketch balance on the boat but it would seem like a lot of work. First you would need to add stays to the main mast to get decent headstay tension which would prevent you from feathering the rig down wind. You would have to pass the tiller extension around the mizzen mast on every tack.

When I bought my CS17 which was rigged like yours with a sleeve luff, I changed it over to sailtrack and slide luff with halyards and two reefpoints in each sail. After using the rig in the grueling Everglades challenge I was very satisfied with the ease in which I could reef for the conditions.

Rob is experimenting with reefing his sleeve luff sails vertically using zippers which looks promising and a number of boats have had good success with reefing their sails by winding them around the mast.

If you want to add some lead ballast, it would be better to add it where it will do the most good - at the bottom of your centerboard. To do this you can cut off the bottom of the centerboard and use it as a mold for a lead piece you can glass on. This would be much better than the lead up higher in a "box".

Also, you should seal the top of your mast...water getting into it is what made your boat so difficult to get up and then made it turn over .

I still feel the VERY FIRST thing you must do is to sail with the main sheet in your control and the minute you feel or see the wind blast let it go. Be sure NOT to dump the mizzen instead. This is the very important point of this rig. You do have to sail it a little differently than a sloop and when you understand it, it is easier.

[Torleif]

Thank you Dave!

I'm glad that you liked Trondheim and the Norwegian nature.

Thank you Graham!

I really apriciate your advises. I allways sail with the mainsheet in my hand when it is gusty conditions or the wind is strong. The two capsizes was caused by gusts coming from slightly different directions. The first one I spilled with the main. Then when I was trying to gain speed again, another one came in more from the side of the boat. I let the mainsheet go and pushed the tiller to get up into the wind, but before the wind lost its grip of the mizzen, the water was coming over the cockpit coaming. This is the reason why I want a smaller mizzen placed further back.

I tried two different reefing systems. First to roll up the main and move the mizzen to the "reefed mast hole". Then a roll reef, where I lock the masts and use the mizzen sprit for the main and a smaller sprit for the mizzen. The first one is very safe but not very effective uppvind in strong wind and heavy sea. The second one I have some trouble to trim because the snotter line is to tight on one tack and to loose on the other. They booth demand a quite heavy operation at sea. This is why I want the mast rail and the jib, to get an easy reefed rig that have good upwind ability even when reefed. That's the theory. I didn't try the mast rail and halyards. Maybee that is the best solution?

If I Lead the center board, how much can I add and still be able to operate the wounderful line control system?

Finally I want to tell that I used the boat a lot in different conditions without any trouble. The dificuties I had in the second capsize comes from my neglect of preparing the boat for capsize and recovery.

Torleif

[Howard]

Torleif's question brings to mind something I've wondered about regarding the cat/ketch rig. On most stayed rigs, (sloop, cutter, ketch, etc), when setup with the proper rig tension, mast rake, sail trim, they develop slight weather helm and will round up if the helm is let go. As long as it's not excessive to the point where the helm stalls and becomes a brake, it's a good thing.

Does a cat/ketch rig develop similar weather helm and round up if the helm is let go (or hit with a gust)? And it may have been discussed, but how does one heave-to to park the boat?

If I understand his problem, the main and mizzen (even if reefed down), or mizzen alone moved to the center position, are not enough sail to drive the boat in the chop and heavy sea, but either combination is too much in the gusts? Sounds like tough conditions for any sailing boat.

On my sloop rig, I'd probably reef way down, and fly my storm jib, but put as much draft in them as possible to power them up, but be ready to dump the main in a puff. On the cat/ketch, do you do the same thing, but just dump the main (head) sail in the puffs? But even if he added a small jib, would he not be overpowered in the gusts?

[Designer]

Yes the cat ketch will develop weather helm /want to round up as the boat heels. The reason sailboats want to round up as the boat heels is because the center of effort or the center of drive moves out to leeward. At the same time, the drag of the hull is still to windward which creates a turning force toward the wind.

I have hove to a number of times in fresh winds by sheeting in the mizzen tight and leaving the tiller alone. This works very well as the mizzen drives the boat up toward the wind and the bow wants to fall off and finds equalibrium at about 30-40deg. from the wind.

I have been in this situation in other boats in the past but I have not experienced it yet in my boats. I believe that my tendency to give my boats more form stability than others helps in this regard because the situation you describe is caused by lack of power to drive through the chop. When you reef, you are adjusting the sail area to the heel of the boat and if the boat is tender, you will have less sail area for a given angle of heel. This can also be exacerbated by the entry of the boat. While racing against a Flying Scot with a CS20 in a good hard beat to windward we noticed that he kept falling back. The FS has lots of form stability but the skipper complained to me that the steep chop with their fairly full bow kept slowing him down.

[Howard]

Perhaps I should have started another thread for this, but it does relate to the sail question at hand.

Some background: In the last two issues of Small Craft Advisor, a guy named Bill Mantis has been exporing what makes windsurfers so fast, and he has carefully detailed the features of the sails they use. Essentially, sails that have an aspect ratio of about 3:1 to 4:1, but have several full battens and the heads that resemble those with small gaffs. They use a wishbone sprit and the springy masts are loaded and tensioned with the downhaul and wishbone sprit. Very similar sail controls to the sprits on the cat/ketch rigs. He also goes on to say that an important safetly feature is the ability of the head of the sail to twist off in the gusts. Essentially, that is how they deal with puffs and gusts.

In Parker's Sharpie book, he has some photos and stories about Egret, a cat/ketch rigged sharpie that carries the reputation of being one of the most sea worthy boats ever built for coastal use, and the book quotes Munroe, the builder, as saying "she could carry full sail in anything". Interesting from the photos that the gaff rigged sails on Egret look almost exactly (shape and proportions) like the sails on the wind surfers. And photos show the heads with much twist to them.

Maybe something along these lines offer the solution to Torleif's problem?

[Brent]

Howard, I was wondering about similiar things. I have seen the masts on my boat bend way over in powerful gusts, and this significantly moderates the impact (by depowering the sail). I was wondering if a mast intentionally designed with more flexibility in the top third may provide the latitude Torleif was needing.

[Stan Robert]

Hi,

Would it be possible to engineer more flex into the tops of the "masts" by changing to gunter-rigged sails - keeping the sail sizes and shapes the same. This would give, effectively, an articulated mast with the bonus of shorter masts for easier stepping and towing behind cars.

Aside from having the complication of a "yard" and not being able to roller-furl, can anyone see why this would not be a good idea?

I have searched the archives of this group and haven't found this question before. Sorry if you've answered this before!

cheers,

Stan

[Guest dvd_godsey]

Here is a notion on the flexible mast notion:

You probably lose a small amount of wind due to flex but they can act as an effective shock absorber and buy you a millisecond of response time.

I am a great advocate of using old windsurfing masts. They average 16 ft in length and there are loads of fiberglass ones to be had for free or cheap since most folks are using sectional carbon fiber units nowadays. They can be stiffened by running a tapered board up the interior and plugged on the ends if you want to lay in resin for bolting, etc.

They are light, nearly indestructable and a great, low cost resource.

Dave Godsey, Nehalem Oregon

[mustangermatt]

I am not sure how much difference the mast flex actually makes. I have oversized solid spruce masts, with oversized full roach sails. Even with those sails the masts only deflect maybe 2 inches at most in a stiff (20 kt) breeze. I haven't noticed any excessive tenderness. But I usually have alot of kids with me :-)

It would be interesting to find another coresound up here built closer to plans and compare.

[Designer]

If the masts are fairly standard there should be be a fair amount of mast bend. If you have too much bend it can de-power the rig too much.

I mentioned earlier about letting the mainsheet out to prevent a capsize when sailing closehauled. This reduces power and helps the boat to round up which further reduces power.

When sailing on a beam reach and hit by a very hard gust it can be desirable to dump the mizzen sheet and bear away. When rounding up from a beam reach in a hard gust, the centrifugal force causes a boat to heel to leeward which when added to the wind force on the sails can capsize a boat. When bearing away suddenly the centrifugal force works the opposite way by reducing heel to leeward and the wind pressure starts acting toward the stern which is more stable. As the boat accelerates away from the wind it further reduces wind pressure.