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PostPosted: Tue Aug 17, 2010 8:20 am 
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When sailing solo, I prefer the rear seat because it seems to go faster. When wind is strong I would like some movable ballast out on the akas near the windward ama to offset heel and reduce drag of leeward ama - all controlled from the cockpit. Any ideas on how to do this using the wind to power the movable ballast? Here are 3 half-baked ideas.

1. water bags strapped between the akas on both sides and interconnected with a valved plastic tube. Pull valve cord to let water flow from one end to the other just before tack using gravity and heeling forces.

2. ballast water containers open on top with remote cord dump control - windward ballast dumped remotely forcing leeward container to submerse just before tack. The stronger the heel force the faster it fills which is in proportion to ballast needed.

3. one water filled ballast that can be moved along guide from one side to the other with cord using force of main sheet - the stronger the wind the higher it hikes out on windward akas.

1 may take too long to move water - even 5 gallons of only 40 llbs. 3 may need too many complex parts that interfere with other functions. 2 seems potentially workable but the drag on the leeward side turns the boat in opposite direction to tack.

Some suggestions or other ideas when sailing the TI solo in high wind?

Bob


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PostPosted: Tue Aug 17, 2010 10:10 am 
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Location: Canyon Lake, Tx
Bob, I was sailing Mark's (TxYackMan) TI yesterday solo and with a passenger and I have a couple of observations...it was light wind sailing but sometimes sailing characteristics can been seen and felt better in light winds...water conditions were pretty flat except for power boat wakes...I noticed that with a passenger that the TI's bow cut through the powerboat wakes more easily than when I was sailing solo...when solo sailing the TI's bow seems to be set higher with the weight in the rear cockpit causing the hull to "slam"...Mark and I discussed that maybe some ballast in water containers in the forward compartment might help balance the boat out more and help with the "slamming" of the exposed flat underside into waves that slows the boat...Mark was sailing along side me in the Fulmar 19 that has a V shaped hull...when sailing through the boat wakes the Fulmar would pull ahead of the TI...Try some water ballast forward and see if that helps...I think Mark is going to try it and see what happens...I don't have much time in a TI so it might just be a WAG...

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PostPosted: Tue Aug 17, 2010 10:43 am 
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Ron,

I also observed the slamming through the wake but hadn't considered its slowing effects. In general, I like the bow riding higher since less drag I would think. I sail on an inland lake and do not have much waves to contend with except powerboat wakes.

I wonder if movable heel ballast between the windward akas would help cutting through the waves since then they would serve as an anti-heel force as well. Part may be due to more mass/momentum. The AI often cannot get through a tack without help from pedaling but the TI seems to do fine - perhaps due to its greater mass.

Bob


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PostPosted: Tue Aug 17, 2010 1:10 pm 
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How 'bout water ballast *in* the amas? One hose connects one ama to the other - in the middle in the front of the rear cockpit sits a reversable 12V pump, a small battery and 3 position switch...

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PostPosted: Tue Aug 17, 2010 2:15 pm 
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Location: Canyon Lake, Tx
Quote:
Some suggestions or other ideas when sailing the TI solo in high wind?

Bob


How about "Reef early and often"??

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PostPosted: Tue Aug 17, 2010 2:54 pm 
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Location: Kailua 96734
Seriously? Sand bags.

Loop a rope through the handles and throw a few in the front seat (or the bow). Then throw them out on the tramps if have those. This is the quickest and cheapest way to experiment.

Or wrap them on the Akas and slide them where you need them. You could rig a pulley on each side.

However, putting a supermodel out there is just as effective. Seriously.

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PostPosted: Tue Aug 17, 2010 5:26 pm 
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Location: Central Coast NSW Australia
Dry bags filled with water are a simpler solution again! :wink:
No lugging any extra weight a great distance. Just fill at waters edge. :)


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PostPosted: Wed Aug 18, 2010 2:01 am 
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Location: Point Lookout, Maryland
I can't get out on the water to go solo when the wind gets up - Cindy is becoming a speed queen and wants to be in on the action! I will say that with her out on the upwind tramp, the rudder behaves a lot better and doesn't act all strained like it does when she isn't hiked out.

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PostPosted: Wed Aug 18, 2010 3:41 am 
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Lots of alternative approaches: reefing, human ballast, and just sailing expertise. If the wind is strong and steady I use reefing but if low wind followed by strong gusts reefing makes it boring. Movable human ballast hiking out can constantly adjust but if solo then what. If gusts are long and can be seen coming then I can prepare by uncleating the main and adjusting at the expense of speed.

The AI seemed to be self correcting in gusts - as it heeled over it turned to wind and thus decreased the heel and drag so speed less compromised. But in the TI it does't seem to turn to wind as fast so more reliant on rudder and main sheet to avoid over heeling. In that case if not reefed, the sail is effectively shrunk in size by the front portion back winded and the rear full. But this has the effect of shifting the center of effort back and thus turning it into the wind slightly but not fast enough to avoid excessive heel and loss of speed. The ideal solution would be twist off where the gusts are dumped as in windsurfing - even human ballast cannot respond fast enough.
But it would be cool to have a corrective system that moved dead weight ballast as it heeled - thus the idea of running the main through a pulley that pulled the ballast further out on the windward aka if possible.

Bob


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PostPosted: Wed Aug 18, 2010 6:26 pm 
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Location: Kailua 96734
H2O ballast. Crazy, interesting concept. Impractical as hell.

But how much water are we talking about? 10-12 gallons? (About the weight of a supermodel).
I know it would mean drilling at least one hole, 1" or better in each outrigger.
You would need a 1500gph 12V pump to do this in 30 seconds or less, but which type?

A sealed low pressure system with intake and exhaust on each Ama?
2 Inline pumps?
A holding tank?
Sealed fresh water or salt water flushing?
What happens to all the air?


You hydrogineers out there have any ideas? Bobco is waiting to pimp his ride. :lol:

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PostPosted: Thu Aug 19, 2010 5:45 am 
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Nohuhu,

I agree. The more I look at it, the more impractical it seems. Yesterday, I had good wind and resorted to constantly reefing/unreefing the sail and the effort to do that was certainly less than any movable water ballast scheme. Since the drag is reduced when reefed, the speed increases - perhaps almost as much as if a had second person hiking out on the windward akas.

Bob


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PostPosted: Thu Aug 19, 2010 6:34 am 
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Location: Saint Johns, Florida
Personally I think 2 models would be more efficient than 1. They would each only have to move between the tramp and the seat and you would have someone in the front seat to take care of the rudder when you need both hands to open a beer.

If one had a red bikini and the other a green one it would prevent you from being confused.

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PostPosted: Mon Sep 06, 2010 12:16 am 
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Location: Brisbane, AUSTRALIA
Can someone assist me please.

I can't find which Hobie accessory catalogue page has these supermodel ballast things on it?

I do not want second hand or old ones as I prefer to buy new but would consider only slightly used. If anyone can help please let me know.

Also consider renting so in future I can trade in for new ones when they get a bit rough around the edges.

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