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  #1  
Old 07-27-2008, 07:38 AM
haaho haaho is offline
 
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Water ballast sail-boat?

Hi, I am looking for plans for a 24-28 f sail boat, with daggerboard and a water ballast system as a main ballast.

My idea is the boat to be light for trailering, and to use diferent weight daggerboards for calm lakes and sea. I saw in internet a boat which was class B or C depends on the keel waight.

I appreciate any help.

excuse my English.
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  #2  
Old 07-27-2008, 04:26 PM
Gary Baigent Gary Baigent is offline
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water ballasted skimmer

Here is my 5.5 x 2.25 metre Cox's Bay Skimmer -a trailerable lightweight dayboat with two mean bunks under the forward cockpit sides, two 6.5 metre wing masts in schooner rig, - design could easily be enlarged to 7 metres or so.
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Water ballast sail-boat?-copy-skimmer2.jpg  Water ballast sail-boat?-copy-skimmer3.jpg  Water ballast sail-boat?-img_1144.jpg  

Water ballast sail-boat?-img_1145.jpg  
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Old 07-27-2008, 05:59 PM
Doug Lord
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Gary, is there something under the water on that boat that I might find interesting?! Cool design!
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Old 07-27-2008, 07:54 PM
Munter Munter is offline
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Check the internet for details of designs by Jim Young. He designed a few water ballasted trailerables a while back.
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  #5  
Old 07-27-2008, 11:30 PM
Gary Baigent Gary Baigent is offline
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skimmer

Nothing special Doug, in fact very basic, just a good shaped dagger and transom hung rudder - the boat is for an architect friend. The original design had two asymmetric daggers that angled out a few degrees from the turn in the bilges, even that now is commonplace with IMOCA and other designs, but of course no lead keel. But two boards require shifting every time you tack and I decided to keep this boat simple. The water ballast will only be used in heavier wind conditions. Rig is low but of large area. Hoping for 120 kgs all up?
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Old 07-28-2008, 06:18 AM
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rwatson rwatson is online now
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28ft water ballast

I am getting one designed at the moment - 28ft, water ballast, twin keels, but also with an outboard option.

Just had the stability calcs done.

The first draft is attached for your info -

Inspiration is drawn from the Mac26, but with self tacking, inspection hatches on the water ballast to put in lead ballast for heavy weather, and to maintain fresh water bladders.
I am looking forward to 500 litres of fresh water on a 28footer - showers every day for a fortnight.

I am also having an internal nav station for heavy weather motoring with the 75hp outboard.
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Last edited by rwatson : 07-28-2008 at 06:24 AM. Reason: extra info.
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  #7  
Old 07-28-2008, 08:49 AM
haaho haaho is offline
 
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Very nice RWATSON, thats exactly my idea. When will it be ready. Tell us more about the lead ballast for heavy weather. Can't you just use different daggeboards?

The 75 hp is too much for me , I am thinking around 10 hp.
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Old 07-28-2008, 05:37 PM
Gary Baigent Gary Baigent is offline
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75 hp?

Surely a typo RWatson? If not, why are you bothering with sails?
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  #9  
Old 07-28-2008, 09:02 PM
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rwatson rwatson is online now
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No - 50-75 hp range is correct, like the Macgregor 26 . Will do around 20 knots with a bit of luck
Sails are for low cost, fun racing, motor is for emergencies, getting to the sailing area or across potentially hazardous stretches quickly and zero or too much wind.

The inspection hatches on the water ballast will be placed so that epoxy covered lead ingots can be placed amongst the baffles, in case I want to attempt some offshore exploration.

Bit more info on the concept at

rough draft of 28ft trailer/sailer/power cruiser with water ballast

Different daggerboards is a great idea. Normally they will be hollow to allow water inside. I will build an extra inlet at the top hole where I could pour leads shot in. Mind if I use the idea?

I am expecting the DXF files for cutting within 8 weeks, after the sailplan and ballast locations are confirmed.

After 18months of frustration, and over $5000, I finally have a designer that is 'in sync' and available.

Now - what to build it of ........... ??

I think the first prototype will be ply, then one in alloy.
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