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 Post subject: down wind speed
PostPosted: Mon Aug 28, 2006 8:25 am 
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Joined: Mon Aug 28, 2006 8:09 am
Posts: 28
Location: Ottawa Canada
Hello, just bought a brand new tiger! Wow what a ride.
The question i have is; what am i looking for to find the fastest course downwind. On my 18 i would use the back side tell tale to indicate stall and thus know we were too low.
With the tiger, the main cant travel out too far before the shrouds interfere. Do i still use the backside tell tails or should i look for something on the spin.
There are no other tigers around to compare


Moyra
(Ottawa)


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 Post subject:
PostPosted: Mon Aug 28, 2006 10:14 am 
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Joined: Thu Nov 13, 2003 10:00 am
Posts: 383
Location: Long Beach, CA
Moyra:

The test to see if you are going fast downwind.

Taking 10 knots of wind for example:

Turn the boat downwind
Set the chute while saillng downwind
center travel the main and sheet it pretty hard
sit at the back crossbar with your crew right next to you
start heading up intil you are really scared to go any more
You should be flying the hull and feel that you are about to go over
At this point you are almost there
Now sail just a bit higher

This is almost exactly the way I found out how to sail downwind.

Later,
Dan


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PostPosted: Mon Aug 28, 2006 2:50 pm 
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Joined: Sun Nov 20, 2005 8:32 pm
Posts: 18
Dan's pretty much nailed it.

A couple of other hints and reasons etc.

1. Keep the main sheeted on "firmly" (and cleated). The main sail is acting as a back stay and supporting the mast against the loads from the kite.

2. As Dan said centre the traveller. Once you get going your apparent wind is going to come a long way fwd. Generally speaking, as your boat accelerates your hull will lift higher, as it does you should slowly bear away. If you are in shifty conditions, or struggling to make a mark you can ease the traveller (not the main sheet) to depower the boat a bit.

3. Generally speaking, if we have no-one on trapeze going upwind then when we turn down hill my crew will go and sit inboard "wild thing" style

If we only just have two on trap upwind. we'll both sit on the windward side down wind, right at the back of the boat.

If we're fully powered up (two on trap upwind without a doubt), then we'll have one crew member on trapeze down wind (me until the first gybe, and my crew after it). This person will usually stand right at the back of the boat. (back foot on the transom, front foot on the back beam.

4. Put a foot strap and/or a chicken line at the back of the boat. Nothing causes a capsize faster than the person on trapeze swinging fwd when you go in the back of a wave.

5. You'll definately capsize a couple of times learning to go down wind fast. Put the kite away, get the boat upright pull it out again and go for.

6. enjoy your new toy.


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PostPosted: Mon Aug 28, 2006 6:43 pm 
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Joined: Mon Aug 28, 2006 8:09 am
Posts: 28
Location: Ottawa Canada
thanks for the responces, hopefully we will look a little more impressive at our next club race!

since people were kind enough to give me pointers downwind, purhaps i can push my luck with a question about upwind. i read the excellent thread 'changing gears on the tiger'. there is a ton of great advise there. a question i have is about footing for spead upwind. from that thread i read that the tiger gets to the windward mark faster by covering more ground but going faster by footing. i am sure experince with the boat will be the best teacher but, we will not get to race againt other tigers untill Madcatter next spring and we must stop looking like a slowbie cat at our club.
in light air conditions, with the jib sheeted moderately, if i head off the wind untill the jib lee tell tail starts to lift then head up a smidge, would this be considered footing enough? too much?

and...we had a hell of a time getting the top battons (the light ones) to pop last race in light air with zero tension. i thought we were going to be DSQed for pumping ourselved back across the startline, any suggestions or does that just suck for us to have brand new super stiff sails?


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 Post subject:
PostPosted: Mon Aug 28, 2006 10:35 pm 
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Joined: Mon Nov 22, 2004 7:18 pm
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Location: League City, Texas, USA
moyra wrote:
and...we had a hell of a time getting the top battons (the light ones) to pop last race in light air with zero tension. i thought we were going to be DSQed for pumping ourselved back across the startline, any suggestions or does that just suck for us to have brand new super stiff sails?


The following seems to work for us in the light stuff:

Crank on the downhaul (Cunningham) hard. This makes it easier to pop the battens over. Plus the boat goes faster in the super light stuff with a fair amount of down haul. This opens up the top of the sail and prevents it hooking to weather (which is dog slow). This then lets you put on a little more main sheet. This keeps the sails flat and lets the air flow reattach quickly when going through chop

As soon as the pressure builds back up to single trap conditions you can let the down haul off to power up - there will then be enough pressure on the top of the main to stop it hooking.

Chris.

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 Post subject:
PostPosted: Wed Aug 30, 2006 1:30 pm 
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Joined: Thu Nov 13, 2003 10:00 am
Posts: 383
Location: Long Beach, CA
My feeling about upwind is that footing starts to work when the wind and seas are up. I am talking 18 plus on the wind and 5ft plus on the swells. Other than that I think that you just point where the boat feels it likes to be presuming that you do not have tons of weather helm. Footing is only 1 to 2 degrees by the way, not like a Hobie 16 which foots at about 5 degrees. You like to get the hull out of the water or at least light and that is about it.

Later,
Dan


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 Post subject:
PostPosted: Tue Sep 05, 2006 5:56 am 
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Joined: Mon Aug 28, 2006 8:09 am
Posts: 28
Location: Ottawa Canada
thanks for the replies.
our racing was cancelled last week do to the hurricane but we got out yesterday in a nice double trapping wind and did a bunch of windward leewards.
we still haven't tried the spin yet, just getting comfortable with the way the boat handles is OK for now (although we are both getting itchy to try it) plus we haven't installed a foot strap yet. (wimp!?)
we moved the forestay to the top hole but the helm is still quite neutral, but not tending as much to lee helm. it is not a problem going upwind or downwind without spin but i wonder how it will be with the spin up. any advice on getting more weather helm other than drilling the rudders and if this is the only option, does anyone have any experience with this?

having fun in Ottawa


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 Post subject:
PostPosted: Tue Sep 05, 2006 8:28 am 
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Joined: Fri Jul 08, 2005 1:30 pm
Posts: 260
Location: Vancouver, WA
You don't have to re-drill to adjust your rudder rake. Pretty much any even vaguely new-ish Hobie has adjustable rake.

Pull the rudders and castings off or turn them all the way to one side - there should be a set-screw in the bottom of the casting. Screw it in a few turns (increases weather helm, which is what you want in this case). Then you have to reset the plate on the top casting where it locks into the cam (loosen the bolt and move the plate back a tiny bit, then retighten). Easier to have someone help you the first time until you see how it works, I think - the system is the same on all the boats so it shouldn't be too hard to find someone to help.

Take the time to measure your rake and rudder alignment while you are at it!

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 Post subject:
PostPosted: Tue Sep 05, 2006 11:14 am 
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Joined: Thu Nov 13, 2003 10:00 am
Posts: 383
Location: Long Beach, CA
If you would like to be able to get the rudder rake right without too much work for testing purposes use tape. You can layer tape in the casting where the rudder sits against it to the point where you have some weather helm.

I had to do this on one side as I had too neutral a helm for my taste. I would sail the boat one time and see if it was enough. If it was not I would add more tape until I got it just right. Then I measured how much tape I had in there. It was a bit less than 1/8 inch. I then put fiberglass and resin on the rudder as a spacer to get that exact distance.

The way that I did this was to put some thin tape in the casting where the fiberglass was going. This is so it will be able to release easily. I measured enough fiberglass to achieve the 1/8 inch and wrapped it at the bedding area on the rudder. I locked the rudder down in sailing position while it dried. I kept some resin in the stir pot next to the boat. When I thought it was hard enough I used a razor knife to clean up the rudder while I could still cut the not completely hard cured resin. While the rudder is still down just cut on top and bottom of the casting where the fiberglass it on the rudder and peel off the excess. It has worked great and the tape experiment allowed me to get it exactly right the first time.

If I were to suggest you do this I would recommend setting your mast rake as well as all the rigging setting to "the book" suggestions. Then start your experiement. This way you will have the rudders set to a fast boat setting.

Later,
Dan


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