Rethinking The Keel

[admin]

Now, with the centerboard boat sailing, and seeing some other keel options, I'm thinking of building a second keel. I'll keep the bulb keel, but for convenience and more frequent use, I'd love to have a lighter keel with either encapsulated ballast or bolt-on ballast that I can slide in and out of the keel box without the bother of a bulb on the end.

I'm considering some different ideas and will put some drawings on this thread for discussion purposes.

Somewhere, either on Sailing Anarchy, or on here, or one the old i550 forum, there were some discussions of a ballasted bulb-less keel, but I can't seem to find them. Any links would be appreciated!

[Warren Nethercote]

Look at how the Gougeon's built 'Yellow Canary'. A time-lapse build is on their web site. They used a ballasted keel, but rather than a bulb they cast the ballast in the same airfoil section in the keel. This allowed full retraction for portaging in the everglades challenge. The same airfoil-shaped ballast could be used on a centreboard end, although a centreboard tackle or winch upgrade would be required.

[Big_Dog]

Tim, Email the PNW group.

[admin]

Thanks, guys. I haven't really dug up much in terms of drawings and such. I'm thinking of something like this, using a laminate of douglas fir. I still have about 50 pounds of #6 shot left.

Ya think?

encapsulated keel.jpg

[Warren Nethercote]

Way too complicated!

Shape the foil and then use a hole saw to cut out a circular bit. Put something to close off one side of the hole and fill and fair it. Then sheath.

[Warren Nethercote]

Or ... use the tip of the keel as a plug to make a concrete or plaster mould and then pour a led tip that is foil shaped. Cut off the tip and fasten on the lead tip and sheath the whole thing.

[admin]

Yep, thought about your 2nd suggestion. I may end up doing that. My main objection was how to fasten it to the upper part of the keel, but I think I have an idea now.

I hate it when I get ideas.....sigh......

[admin]

OK, here's the plan. Yesterday I ripped some douglas fir 4x4''s and will laminate these and build a foil. I'll ballast this thing one way or the other. Bottom line is: this is going to be a lighter, more user-friendly foil for light air (e.g., the usual sailing conditions on the Chesapeake) and I'll use two Group 27 batteries to add 130 pounds of internal righting moment, strapped in on each side of the keel box.

I use an electric trolling motor, and it'll be good to have a spare battery for motoring and nav lights after dusk. Keep ya posted -- I'm interesting in how this will affect stability...I doubt the boat will be self-righting, although perhaps. Feel free to chime in on that!

Douglas T Fir.jpg

[Thomas]

I have been sailing with a 23 lb centerboard for as long as I launched the boat ,all good as long as it blows 10 or below . The boat is fast in light air ,a lot faster then most boats really.
I added a code 0, 237 sq foot , furling , easy the way it is suppose to be . Sailing with an extra crew , meaning adding 180lb - 200 lb plus pound is a big plus. Never dipped the rails
Yet , even so a few times gust hit so hard I had to luff ,pinch right into the wind .
I planning to built another board or router into the one I got and add 40- 60 lb of lead but had little inspiration since I finished the boat . Adding reef is a better solution then lead ,it will only slow you down in light air .
http://sailnaway.blogspot.com/2014/04/a ... oject.html
http://www.bluestempaddler.com/sootyter ... s-mounted/
Let me know how its done .

[Thomas]

New years day regatta wind 5-7 mph , 4.1 knots boat speed

[Tim Ford]

Excellent info, Thomas, and thanks very much!

Those two links are brilliant and anything by the Gougeons is always good! I'm PSYCHED!

[admin]

Anudder question: who built your Code Zero for you? (what loft?) I'm thinking along the same lines with a top-down furler. Raced on a friends tri with a top down furler and they are the shizz-nizzle!

[Thomas]

Waters Sails
Joe Waters
tel 803 957.50 40
www.waterssails.net

Great guy , beautiful work .

[Tim Ford]

Started the new keel lamination! Can't wait til the actual shaping process begins.

firkeel.jpg

[Thomas]

Tim
Using the Naca 12 foil is very old concept . I used Naca 59 , or even go to Naca 60 ,
http://airfoiltools.com/airfoil/details?airfoil=e59-il , the yellow line .
Just a thought .
Thomas

[Thomas]

Looking back at my old files I actully used Naca 65
http://airfoiltools.com/airfoil/details ... ca65210-il

[Tim Ford]

Hmm....I'd consider a different foil shape if I hadn't already installed acetal guides already. I liked the 0012 due to it's lift/stall coefficients. The boat sailed well with that foil. That is, when I could get the damn thing all the way down...not to mention all the way back up

Thanks though!

[Tim Ford]

A bit more progress on the "speed keel" -- can't wait to try this thing!

speedkeel3.jpg

speedkeel2.jpg

[micah202]

Now, with the centerboard boat sailing, and seeing some other keel options, I'm thinking of building a second keel. I'll keep the bulb keel, but for convenience and more frequent use, I'd love to have a lighter keel with either encapsulated ballast or bolt-on ballast that I can slide in and out of the keel box without the bother of a bulb on the end.

I'm considering some different ideas and will put some drawings on this thread for discussion purposes.

Somewhere, either on Sailing Anarchy, or on here, or one the old i550 forum, there were some discussions of a ballasted bulb-less keel, but I can't seem to find them. Any links would be appreciated!

....there was discussion of this idea on the SA thread.
There are manufacturers of hollow alloy finns for sportboats, these could be filled with lead castings or shot.

[Marino]

Tim, how much weight in lead will you be putting on? or nothing at all?

[Tim Ford]

Hi Marino, I'm going to pour in a bunch of lead shot. I have 28 lbs left of #8 lead. Maybe another 10-15 pounds after that. The laminated keel weighs about 25-30 pounds as it is. So total weight between 55-70 pounds when I'm done. And another Group 27 in the slot
up by the mast step should be a lot of dead weight but I have no idea of what the RM (righting moment) will be.

Tell you one thing, first couple of sails will be in the LIght stuff....

[Marino]

Hi Tim, thanks for replying back. Not knowing the wind conditions on the lake you sail, why not first try sailing only with the new keel design and see how that goes first?

[Tim Ford]

Not sure I follow you: you mean try the redesign of the old keel? The one I stripped all the fiberglass off and shaved down a little? I may try it a bit later this summer, but the first few go-arounds will be with the new straight (bulb-less) keel.

The "lake" I sail on is 200 miles long and 30 miles wide at it's widest point, averages just 11' deep. It's really a swollen river valley (the Susquehanna) and it's regular name is The Chesapeake Bay

[Marino]

The one you are pouring the lead into. Would be interesting to see how the boat performance and handles.
That's a BIG lake.

[micah202]

Yah, I don't think the keel weight comes into play at all, until the boat is laying on the side panel. Did that once, messing around between races.

...at that point, you may just wish to have some weight there.