How many water ballast trailer sailers are there?

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I've heard of Macgregeor and Hunters but I'd never heard of the Dehler 25 until someone plonked one next to my boat in the yard.
Are there any others?
the term "water ballast" seems to confuse the hell out of google.
 

John the kiwi

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I have a Young 780 which is a water ballasted 7.8 metre GOP trailer yacht designed by Jim Young in New Zealand.
Jim Young was a prolific designer and a keen racing sailor so even my boat which was designed for accommodation and low weight on the trailer is reasonably nimble - unlike a Macgregor for example.
(OTOH, I dont have a 50 hp motor and can't waterski behind my boat.)
The design is from an era when the family car was a 2 litre sedan or 2.4 if you were posh and the idea was to make a largish boat that could be trailed without needing a truck.
I have toyed with the idea of substituting lead for water and loading up the centreboard weight as well to increase stiffness, but probably wont make the investment.
I use a 12 volt mattress inflator to suck in or blow out the ballast water and being able to "blow all tanks" and reduce draught when going into lagoons for a night is quite cool.
I'd be surprised if any Young water ballast designs were in the UK, but the water ballast principle is entirely sound.
I have seen where some people on forums have tried to "prove" that water ballast doesn't work, but all they prove is their own ignorance of simple physics.
There is no question that for a performance monohull, a large lump of lead or better still, depleted uranium on the end of the keel is the best thing. Where i sail though, my boat will beat your fixed keel boat because i will be over the bar and gone hours before you can leave harbour.
Just shows all over again that all boat designs are a floating set of compromises.
Cheers
 

jakeroyd

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I think the issue with water ballast is there is no problem if the volume you are filling is full completely with water.
If so then this is effective cos water is heavy stuff as we all know.
If a volume/tank is not full then it can slosh about affecting trim and stressing the tank ?
 
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I have a Young 780 which is a water ballasted 7.8 metre GOP trailer yacht designed by Jim Young in New Zealand.


Just shows all over again that all boat designs are a floating set of compromises.
Cheers

Thanks for all the replies so far.

Cecil Kimber, the man behind MG cars would like the 780 as it "looks fast standing still".:encouragement:

Having owned a Seal 22 for a few months I've decided I prefer a different set of compromises. As I am inland and intend using lakes etc. I am drawn towards ease of trailing/launching, and better accomodation if I'm changing boats.
Out of those mentioned so far I think in practical terms it will be a choice between the three I mentioned before.
 

maby

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I think the issue with water ballast is there is no problem if the volume you are filling is full completely with water.
If so then this is effective cos water is heavy stuff as we all know.
If a volume/tank is not full then it can slosh about affecting trim and stressing the tank ?

If the tank is not full, then it does nothing - the water just slops from one side to the other
 

Seajet

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If the tank is not full, then it does nothing - the water just slops from one side to the other

But it will go to the downhill leeward side, wheras a full tank might contribute a bit towards righting moment !

Until you get to the stage where you can pump water side to side in tanks at the beam width of the boat, water ballast is pretty inefectual; even boats with lead or iron internal ballast don't stand up very well.

Just about Ok on a lake, but I've seen it get pretty lumpy on Windermere and the regular katabatic squalls on most lakes will be fairly unwelcome on a lightly ballasted boat; are you staying onboard overnght ? If not, a dinghy and a tent / camper van / B&B might be a better bet, safer and more fun ?
 
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But it will go to the downhill leeward side, wheras a full tank might contribute a bit towards righting moment !

Until you get to the stage where you can pump water side to side in tanks at the beam width of the boat, water ballast is pretty inefectual; even boats with lead or iron internal ballast don't stand up very well.

Just about Ok on a lake, but I've seen it get pretty lumpy on Windermere and the regular katabatic squalls on most lakes will be fairly unwelcome on a lightly ballasted boat; are you staying onboard overnght ? If not, a dinghy and a tent / camper van / B&B might be a better bet, safer and more fun ?

Blimey! I've just had to look up "katabatic". It has to the word of the day for tomorrow; try and get it into conversations at work.

Why would anyone partially fill their water ballast? Could you partially fill it by accident? The Dehler system is automatic with air bleed valves if my information is correct, and if it isn't we'll soon hear about it.

I've read in other places that a WB boat heels over quickly to about 15 degrees then goes quite solid. In his promo video for the 26M, Macgregor stands on the extreme of the boat to demonstrate a lack of movement, is he cheating?
 

Seajet

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It's going to depend on how much water ballast, where it is in the boat design, and if it's a wide boat with ' form stability ' as well as the rather poor ' ballast stability ' conferred by water then it will be more stable than a pencil thin design with a one gallon jerrycan on the cabin sole !

Water ballast is helpful for trailing, but so is a trailer and not many boats set off in boat mode with those; unless one goes to extremes like a racer and pumps it side to side, it's not much use as ballast, people use cast iron or lead, several feet below the hull, for good reason.

I've enjoyed katabatic squalls at Studland Bay too, the nasty thing is as they blow downwards not along the surface like the winds we're used to, heeling - whether with sails or just bare poles - presents more area rather than spilling wind so she'll go further over, relying on every bit of stability she has, form and ballast - and crew weight if available - to bring her back upright.

It's even nastier if in an aircraft like a glider, microlight etc, getting pushed down on the leeward side of a hill is known as getting ' rotored ' and has been known to be fatal.
 

AngusMcDoon

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I've read in other places that a WB boat heels over quickly to about 15 degrees then goes quite solid.

You have to remember Seajet's rule of boats and stuff : if it's on his boat, is his boat or is a Harrier, it's wonderful, the greatest, fantastic, the best, bombproof, go anywhere and so on ad nauseum; everything else is utter rubbish.
 
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You have to remember Seajet's rule of boats and stuff : if it's on his boat, is his boat or is a Harrier, it's wonderful, the greatest, fantastic, the best, bombproof, go anywhere and so on ad nauseum; everything else is utter rubbish.

Shouldn't you add a smiley to the end of that as you are besy mates?

That's it then; I'll get a couple of Harrier drop tanks, nail them to the side of an Anderson 22 and flood them. Water ballast!
 

AngusMcDoon

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Blimey! I've just had to look up "katabatic". It has to the word of the day for tomorrow; try and get it into conversations at work.

Get the context right though. :) They are formed by intense cooling of air at height compared to the air at lower level making it significantly denser so that it rushes down the slope. Common in Greenland, Antarctica, Canada, Patagonia and other places where there is snow cover at height to cool the air. You don't get them in Studland Bay; there's not the temperature difference at the modest height of the adjacent hill to drive them. That's just turbulence on the lee side of a hill affecting the bog standard gradient wind - a very common effect in West coast Scottish waters.
 
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Get the context right though. :) They are formed by intense cooling of air at height compared to the air at lower level making it significantly denser so that it rushes down the slope. Common in Greenland, Antarctica, Canada, Patagonia and other places where there is snow cover at height to cool the air. You don't get them in Studland Bay; there's not the temperature difference at the modest height of the adjacent hill to drive them. That's just turbulence on the lee side of a hill affecting the bog standard gradient wind - a very common effect in West coast Scottish waters.

Thanks, I'll bring it up at the water cooler.:rolleyes:
 

Seajet

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Shouldn't you add a smiley to the end of that as you are besy mates?

That's it then; I'll get a couple of Harrier drop tanks, nail them to the side of an Anderson 22 and flood them. Water ballast!

What size drop tanks ? if empty that would make a buoyant, boat shaped version of Angus's boat wouldn't it ?! :)
 
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Get the context right though. :) They are formed by intense cooling of air at height compared to the air at lower level making it significantly denser so that it rushes down the slope. Common in Greenland, Antarctica, Canada, Patagonia and other places where there is snow cover at height to cool the air. You don't get them in Studland Bay; there's not the temperature difference at the modest height of the adjacent hill to drive them. That's just turbulence on the lee side of a hill affecting the bog standard gradient wind - a very common effect in West coast Scottish waters.

Oh. A fart doesn't qualify then. That's ruined a joke I'd just written.
 
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