How about centerboard instead dagger bulb keel .

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How about centerboard instead dagger bulb keel .

Postby Thomas » Tue Feb 27, 2018 1:30 am

I been sailing dingy' s all my life , raced Flying Dutchman , H0bie 16 , trapeze is the ballast .just a thought .
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Re: How about centerboard instead dagger bulb keel .

Postby Mist » Tue Feb 27, 2018 2:18 pm

I think no ballast is setting one up for a big mess on the i550. I experienced a pretty good sized knockdown with asym up. The boat laid over on it’s side until we released the asym halyard and mainsheet. The crew was tossed in the water on the low side (no counter ballast provide). Eventually, the boat came upright. I don’t think that would have happened without the 155 lb bulb. Without the ballast I think the mast would have stuck itself in the mud.

Anyways, I’m considering making a foil shaped lead ballasted centerboard to accommodate sailing in shallow water. I haven’t done the math to figure how much ballast the foil shape will produce but is got to be better than just a wood foil.

My experience with the i550 is that there is just too much going, all the time, to be able to work a trapeze system to. Maybe I’m too old, weak, and out of shape??? If you go the route of no ballast and traps, I wish you well! You’ll be much more a sailor then I am.

It’s great to hear your building in Georgia. I really think we could get a group of boats together on lake Murray in Columbia SC in the future.

Enjoy building! It’s fun!
Mist i550 #296 Tim K
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Re: How about centerboard instead dagger bulb keel .

Postby Warren Nethercote » Tue Feb 27, 2018 10:18 pm

If you go to Leon's Facebook page (PhattAss in South Africa) you will find that he suffered a knockdown on the very day he'd forgotten to secure the keel down after trailer launching. The keel slid back into retracted position and the boat turned turtle, and then flooded through the companionway. It took some effort to recover the boat. A ballasted daggerboard like Yellow Canary is probably more efficient than a ballasted centerboard through better aspect ratio and absence of the need for centerboard trunk gaskets.
Last edited by Warren Nethercote on Wed Feb 28, 2018 8:46 am, edited 1 time in total.
Warren Nethercote
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Re: How about centerboard instead dagger bulb keel .

Postby Thomas » Tue Feb 27, 2018 11:31 pm

I was just weighing all options , I do like the idea of a foil shaped centerboard .
Have made the stem post ,only a whole boat to built now,.
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Re: How about centerboard instead dagger bulb keel .

Postby ryderp » Tue Feb 27, 2018 11:34 pm

I think that it would be a major mistake to use an un-ballasted centerboard on your i550. Before the i550, we had an e-scow. We had a set of sails for the e-scow with floats on the top to prevent turtling, but a knockdown was still a significant event. One of the reasons we moved to the i550 was to get away from humans being the only ballast on the boat. I've had my i550 on its ear a few times, and it has popped right back up once the pressure was eased off the sails.

As to the other half of your comment/question: I'm planning on adding trapezes to my boat. It's not in the class rules, but I think that it would be fun, and the rails on an i550 are in the water a lot.
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Re: How about centerboard instead dagger bulb keel .

Postby admin » Wed Feb 28, 2018 4:36 pm

I am in agreement, with Phil's comment, but it depends on who your crew is and what kind of sailing you're thinking of in the future. If you have really talented, athletic crew (younger) then you might have fun with just a board down. I don't like the idea of big wide-open companionway being exposed in any sort of wave state, though.

Coincidentally, I have been playing around with a ballpoint pen and a cocktail napkin recently to think about how to build a ballasted wooden daggerboard. I'm not sure the bulb and foil is the best idea for a grassy river like I have here. I don't like backing down due the rudder loads and I hate swimming in sea-nettle season.

Traps would be cool, if you come up with a workable plan, Phil, I'd love to see your set up.
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Re: How about centerboard instead dagger bulb keel .

Postby Warren Nethercote » Wed Feb 28, 2018 9:48 pm

if you were to relocate the bulb so it doesn't project forward of the foil leading edge you could add a kelp cutter like the j70. A ballasted dagger board is still likely to need a cutter or flossing. A keel will probably not shed weed unless it is heavily raked.
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Re: How about centerboard instead dagger bulb keel .

Postby Warren Nethercote » Thu Mar 01, 2018 8:14 am

As a supplemental. 'When I was younger' I sailed International 14s and the occasional 470, mostly as crew but sometimes as helm. Crewing was waaaay better because the trapeze was easier than hiking. But, then I had knees that worked.
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Re: How about centerboard instead dagger bulb keel .

Postby Tim Ford » Thu Mar 01, 2018 5:16 pm

Warren Nethercote wrote:if you were to relocate the bulb so it doesn't project forward of the foil leading edge you could add a kelp cutter like the j70. A ballasted dagger board is still likely to need a cutter or flossing. A keel will probably not shed weed unless it is heavily raked.


I was thinking more of the ability to lift the keel entirely so that the trunk would floss the board.

Yes, you are right about the straight keel not shedding weed evenly. We used to race the J24 out of a marina way up the bay that was heavily choked with fanwort. You know how raked a J24 keel is.

Heading out to the race course, the boat felt slow so we backed down. Boat still felt loggy, so I jumped over and swam under to the keel. Holy crap! We must have had 150 pounds of fanwort on there. I ran out of breath trying to free the keel and popped up to the surface, gasping, and said, "guys, I'm going to need to dive down with a rope and when I give the signal, put it around a winch and go hard with a handle...it's like we have a human body wrapped around the keel."

True story!
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