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PostPosted: Thu Jul 15, 2010 8:31 pm 
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Dan P. wrote:
Loosening the downhaul. Good topic to discuss - I was under the impression that downwind downhaul/cunningham loosening has one purpose, which is mainsail shape. I had never considered that a mainsail tear could result from forgetting to loosen it before launching the spi. Makes sense though. Is anyone out there knowledgeable about this?



You don't loosen the downhaul to protect the mainsail, its to protect the mast. the downhaul causes the top of the mast to fall off, and in the case of having the spinnaker up it'll pull it out of whack enough that you could break it.

Both the Tiger and FXone masts are fricken barn poles, especially in the case of the FXone. It would have to be flat out nuclear for either of those masts to break from just losing the main sheet. Typically even with a wing mast, or what is essentially an A-cat mast on my boat, you have to stuff it, and lose the main to have any real issues.

Main things are to release the rotator and allow it to rotate fully, so the diamond wires can take up some of the load from the spinnaker, and to ease the downhaul. In light air you may want some downhaul on to get a good shape though.

I used to just crank on the main sheet when I put the spinnaker up, but I was always over sheated when going downwind and not getting good flow on the main sail, which is still providing some drive as the main basically thinks its going upwind. So you still have to trim accordingly and keep the leach tells flowing appropriately.


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PostPosted: Fri Jul 16, 2010 3:35 pm 
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Hi Karl (are you sailing a Tiger now?? - I thought you were headed for F16 land) Thanks for the great input. It is interesting, the majority of my pondering in the area of cats is about improving performance, not keeping the boat from self destructing. Fun topic. Which telltales are you using with spi up? - I use jib.

Jeremy - I didn't know you were a musician! I've been a guitar operator for about 38 years. We should jam. My main instrument is piano (20th-c stuff & composing) so my guitar "rock" songs are unorthodox and high energy (from ska to folk to metal). And, unless you are John Galt, my lyrics will just piss you off!

Peace,

Dan Peake
Campbell, CA
05 FX1
02 Tiger


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PostPosted: Mon Jul 19, 2010 7:34 pm 
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Dan P. wrote:
Hi Karl (are you sailing a Tiger now?? - I thought you were headed for F16 land) Thanks for the great input. It is interesting, the majority of my pondering in the area of cats is about improving performance, not keeping the boat from self destructing. Fun topic. Which telltales are you using with spi up? - I use jib.



I'm sorta in limbo right now. I bought a 09' Viper, which I just sold a few weeks ago, and now I'm awaiting my 10' Viper to show up. I'm contemplating buying an A-Cat to fill in while I wait. Wild thing downwind with an A-Cat is an absolute blast!


More than anything I look at the leach tells at the top. That's the first thing I look at in sail trim. I usually throw three at the top, inbetween #1&#2 battens, inbetween #2&#3 battens, and inbetween #3&#4 battens. The 2nd tell tale being the most important for how hard you should be sheated, (provided downhaul and your angle to the wind is correct to begin with). You want those tells to be just hooking, then flying back, then hooking, then flying back, then..... etcetera. If its light I will pull on some downhaul, and possibly a little bit of rotation with the chute up. With the FXone there's pretty minimal risk even if its blowing out, the loads just aren't that high compared to a F18. With the F16 most have a mast that isn't nearly as robust as the bigger boats, and they do require being a bit more conservative. The Goodall wingmast that most of the US F16's are using, (Falcon, Blade, Viper), is just an old aluminum A-Cat extrusion, so not real forgiving to misuse.


When sailing with a jib I use the jib tells for steering while going upwind if the wind is too light to do so off of feel. Downwind I do a couple of different things. If there is enough wind to fly a hull, then I'm steering almost strictly off of windward hull height, that also applies if I, or the crew is on the wire. If I can't fly a hull, then I'm boards up and trying to sail the best angles I can, and I definitely don't get it right often enough, its an experience thing I think. If it gets super light, (like when its tough to keep the spinnaker filled :evil: ). boards stay up, and I drop off some traveller.

My last few spinnakers have had tell tales on them, there's only a very small window of conditions that I even look at them. Some people use them solely. I sheet almost solely on the curl of the luff on the spinnaker, you want that just winking at you, so pretty much always on the verge of collapsing. You do have to get your luff tension setup correctly, most have there's set way too loosely for modern, (ie flatter cut), spinnakers. Which the cuts keep getting flatter and flatter.


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PostPosted: Mon Jul 19, 2010 11:09 pm 
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Location: Campbell, CA
Hi Karl,

Thanks for the info.

In super light air have you had any luck letting off 20-30cm of head (Cant be done on my FX, but I have spi tack and head on my Tiger.) Similar topic - any improvement pointing when you tighten the head and let out 20-30cm of tack?

What is the procedure for adjusting spi luff tension?

Why the quick succession of Vipers?

A-Cat Wild-thing: One of my favorite things to do, (FX1, Tiger, going beck to my 17's) is wild-thing down wind. I considered getting a GPS to measure the speed, then realized I'd be disappointed if it turned out to be something unimpressive like 11kts! It is an amazing blast though. Is the A-cat markedly better, thrill wise, than the FX1 (no spi) in down wind wild-thing ops?

Peace,

Dan Peake
Campbell, CA
05 FX1
02 Tiger


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PostPosted: Tue Jul 20, 2010 7:23 am 
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Location: Northfield Minnesota
Dan P. wrote:
In super light air have you had any luck letting off 20-30cm of head (Cant be done on my FX, but I have spi tack and head on my Tiger.) Similar topic - any improvement pointing when you tighten the head and let out 20-30cm of tack?


I've never tried it. At this year's Alter Cup one of the teams were able to carry the chute up wind a ways doing that, and they did make up quite a bit of ground. I don't think you can tack with it up though and it has to be dropped before you tack. It depends on how you're sailing, (1up vs 2up), if you overstand a mark with the spinnaker up. 2up crew goes on the wire, if it still isn't enough play the main traveller, if its still not enough I'll go as far as I can travelled out and hope for a shift or the wind to let up. If it doesn't, then you need to drop the chute and reach into the mark.


Dan P. wrote:
What is the procedure for adjusting spi luff tension?


A few things. Raise/Lower the bail at the mast. Raise/lower the spinnaker pole. Some spinnakers have a luff cord making it semi adjustable as well. You need to measure the luff of the spinnaker, then tie a tape measure off to the halyard then hoist the tape measure and find out what the distance is to the end of the pole. I don't remember what the percentages are for sure, but I think you want to be 2-3% longer than what the luff of the spinnaker measures laying on the ground.

Dan P. wrote:
Why the quick succession of Vipers?


I bought the first one with the same intentions I did when I bought the FXone, and that was to sell it locally and grow the fleet. Just really poor timing for me, as there aren't any new Vipers available.

Dan P. wrote:
Is the A-cat markedly better, thrill wise, than the FX1 (no spi) in down wind wild-thing ops?


I never really tried to wild thing the FXone, I should have as it took me quite a while to figure out how to drive it in heavy air down wind with the spinnaker up. Wild thing is a tricky beast too, so...... Its real easy to lose track of angles and end up reaching around for no reason.


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PostPosted: Thu Nov 11, 2010 2:13 am 
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So am I reading right, let your mast rotation off, increasing mast rotation when flying a kite? I have always believed the opposite. Increasing mast rotation allows the spinnaker to pull more side on to the mast where the section is narrower, the diamond wires do not support the top section where the spinnaker attaches therefore damage is more likely to occur? I bring in the spanner line to reduce mast rotation (spanner pointing to end of rear beam) I believe this is best and I haven’t had any problems. So what’s right?


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PostPosted: Fri Nov 12, 2010 7:33 pm 
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Mast rotation off.


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PostPosted: Sat Nov 13, 2010 5:50 am 
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Karl Brogger wrote:
Mast rotation off.

I’m sorry, I take your word but I still struggle to accept this.

Mast rotation off, as in increasing mast rotation? Even in stronger wind where mast breakages are more likely and sail camber is less sort after?

If a vector was to be drawn for the pull of the spinnaker in relationship to the boat, I would guess that the major pull would be forward, then to leeward. At worse case, forward and 45 degrees to leeward. Yes?

The mast should only ever break above the hound, where it is not supported by diamond wires. Therefore we can ignore the strength of diamond wires. The mast is far stronger front to back than it is to the side, due to the larger section. Yes?

If you let mast rotation off, the pull of the spinnaker is going to move closer to side on to section the mast, where the mast is weaker, therefore increasing the likely hood of breaking your mast????

I understand the main sail acts as a very effective aft stay, perhaps overruling the need to keep the mast section parallel with the boat and forward pull of the spinnaker???? And allowing the mast to rotate around presents a stiffer section to the leeward pull of the spinnaker?

I’m happy for anyone to prove me wrong, until then I think I am going to continue to haul in the mast rotation in heavy winds.


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PostPosted: Sat Nov 13, 2010 5:54 am 
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So yea I am 50/50 at this point haha. Hope it doesnt blow up too much for racing tomorrow or I am going to be thrown into a state indecision.


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PostPosted: Sat Nov 13, 2010 4:46 pm 
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The strength is in the diamond wires. Believe what you want, not my boat.


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PostPosted: Sun Nov 14, 2010 11:45 am 
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Karl Brogger wrote:
The strength is in the diamond wires. Believe what you want, not my boat.


The diamond wires finish before the hound, what strengthens the mast above there?

Talking today, as far as I can tell, the masts are very strong, mast rotation is irrelavant, just ensure you keep your mainsheet hard in.


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