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Re: Blade F18 video [Re: Inter_Michael] #68842
03/12/06 07:13 PM
03/12/06 07:13 PM
Joined: Jun 2003
Posts: 887
Crofton, MD
Chris9 Offline
old hand
Chris9  Offline
old hand

Joined: Jun 2003
Posts: 887
Crofton, MD
Inter_Michael,

How did you run the line? It doesn't get in the way of snuffing? Diagram?


Chris Allen
Nacra 20 Gertie
www.wrcra.org
-- Have You Seen This? --
Re: Blade F18 video [Re: Jake] #68843
03/13/06 01:26 PM
03/13/06 01:26 PM
Joined: Nov 2002
Posts: 606
League City, TX
flumpmaster Offline
addict
flumpmaster  Offline
addict

Joined: Nov 2002
Posts: 606
League City, TX
Quote
We spent probably about 40% of last year's 523 mile Tybee 500 running as high and tight as possible with the spinnaker. I will attest that the loads are quite high - most of the crews hands (including mine) really paid the price. The truely grueling fact was that the spinnaker was adding a lot of drag for the power it generated - we were getting about an extra .2 knots out of it for all the work going into it...but we were racing!


Jake,

Did you run a doubler on the spin sheet to ease the loads. We've found this really helps on crew fatigue when carrying the kite high on distance races. We tied a pigtail to the clew of the kite with a carbo block on it and tied a stopper knot in the end of the spin sheet. When you want to deploy the doubler you draw the stopper knot back from the pulley to a hook attached to the shroud adjuster (or on top of your spinnaker turning block on the hull).

Chris.


Dave Ingram is my president. tcdyc rules
Re: Blade F18 video [Re: flumpmaster] #68844
03/13/06 01:30 PM
03/13/06 01:30 PM
Joined: May 2002
Posts: 3,114
BANNED
MauganN20 Offline
Carpal Tunnel
MauganN20  Offline
Carpal Tunnel

Joined: May 2002
Posts: 3,114
BANNED
no doubler

the doubler is to slow when playing the curl of the luff.

Re: Blade F18 video [Re: flumpmaster] #68845
03/13/06 02:10 PM
03/13/06 02:10 PM
Joined: Jun 2001
Posts: 12,310
South Carolina
Jake Offline
Carpal Tunnel
Jake  Offline
Carpal Tunnel

Joined: Jun 2001
Posts: 12,310
South Carolina
nah...I don't think Carl would have had enough patience for me to go to the low side to cleat it...he and I share similar focus levels. Running so high, I wonder if with 2:1 if I could react fast enough to a collapsing kite.


Jake Kohl
Re: Blade F18 video [Re: Jake] #68846
03/13/06 02:59 PM
03/13/06 02:59 PM
Joined: May 2002
Posts: 3,114
BANNED
MauganN20 Offline
Carpal Tunnel
MauganN20  Offline
Carpal Tunnel

Joined: May 2002
Posts: 3,114
BANNED
no doubler needed, just use your legs to pull the line. Wrap it around your arm a couple times so you can grip it.

Or use jake's gauntlet.

Re: Blade F18 video [Re: Jake] #68847
03/13/06 04:14 PM
03/13/06 04:14 PM
Joined: Jun 2002
Posts: 806
Toronto, Ontario
pitchpoledave Offline
old hand
pitchpoledave  Offline
old hand

Joined: Jun 2002
Posts: 806
Toronto, Ontario
Yes, the 2:1 works great. I wouldn't do a long distance event without it..

Re: Blade F18 video [Re: Rolf_Nilsen] #68848
03/13/06 04:35 PM
03/13/06 04:35 PM
Joined: Nov 2005
Posts: 807
Hillsborough, NC USA
I
Isotope235 Offline
old hand
Isotope235  Offline
old hand
I

Joined: Nov 2005
Posts: 807
Hillsborough, NC USA
Quote
I suggest you listen to the lyrics while looking at the different scenes, this is obviously done with great consideration.


Yeah, I kept waiting for the line "She's so fine, there's no telling where the money went".

Regards,
Eric

Re: Blade F18 video [Re: MauganN20] #68849
03/13/06 09:03 PM
03/13/06 09:03 PM
Joined: Jul 2001
Posts: 851
US Western Continental Shelf
hobiegary Offline
old hand
hobiegary  Offline
old hand

Joined: Jul 2001
Posts: 851
US Western Continental Shelf
If you take a look at the beautiful job that Performance Catamarans of Santa Ana, California did on the new Nacra 580, you'll find that a kick up centerboard, that has a proper foil shape, can indeed be self sealing with no added gaskets.
Pictures of the Nacra 580 with kick up centerboards

This centerboard seals the trunk when it is fully retracted and it also seals the trunk when it is fully extended.

Flashback in time: Check out my April Fools Post from 2003:

Quote
A Nacra Formula 20 CB is the centerboard version of the F20 boat
that is based on their new F18. The hull shapes are very similar to
the newer Nacra F18 but a bit larger. They are narrow, have a very
fine entry, tall plumb bows, and a super-cool ultra thin walled
chromium-alloy (chromolly) super strong and lightweight mast that
has better flex characteristics than other current aluminum or
carbon fiber masts.

The centerboards are high aspect ratio eliptical shaped foils that
employ a new centerboard gasketing system that provides a near
perfect seal in all the centerboard trunk that is not occupied by
the long slender foil. When the boards are lifted half way up, they
swing so far aft that the center of lateral resistance is moved
significanlty aft and thus provides a superior resistance to
broaching.

It's my dream; very much a dream boat!

GARY
post



GARY

Attached Files
69667-nacra580 (2).jpg (52 downloads)

Santa Monica Bay
Mystere 6.0 "Whisk" <--- R.I.P.
Re: Blade F18 video [Re: hobiegary] #68850
03/14/06 01:47 AM
03/14/06 01:47 AM
Joined: May 2003
Posts: 4,451
West coast of Norway
Rolf_Nilsen Offline
Carpal Tunnel
Rolf_Nilsen  Offline
Carpal Tunnel

Joined: May 2003
Posts: 4,451
West coast of Norway
That daggerboard is a bit to short with too long a chord for my taste. The sealing part of it could use some adjustment to fit the hulls properly
But kickup daggers would be great on a distance racer, no reason to worry too much about what you can hit with them. The extra weight added to the kickup mechanism can probably be re-gained as you dont have to reinforce the daggerboard well and bulkheads around it as heavily. I like it a lot! Just need a working and robust mechanism.
Have you tought about starting a fortune-telling business Gary? Seems like you are plenty succesful at it, or is your talent limited to beachcats?

Re: Blade F18 video [Re: hobiegary] #68851
03/14/06 03:13 AM
03/14/06 03:13 AM
Joined: Jun 2001
Posts: 9,582
North-West Europe
Wouter Offline OP
Carpal Tunnel
Wouter  Offline OP
Carpal Tunnel

Joined: Jun 2001
Posts: 9,582
North-West Europe

Pardon my french here but what a non-informative post that turned out to be. Look at it was stated :


Quote

A Nacra Formula 20 CB is the centerboard version of the F20 boat
that is based on their new F18.


Both info elements in this sentence are just plain non-sense. It was actually just a centreboard version on the Nacra 5.8; that is even reflected in its name. It DOES NOT comply with F20 rules; it is not heavy enough. So that info element was non-sense as well.


Quote

The hull shapes are very similar to
the newer Nacra F18 but a bit larger.



Not really, the hullshapes are more like the old nacra's; the N5.2's, N5.5's, N5.8's and even N5.7's, then the nacra F18.


Quote

They are narrow, have a very
fine entry, tall plumb bows,



What is narrow on a catamaran. I think the hulls to be rather medium in the way of narrowness. And it doesn't have a plumb bow like the Inters. Tall ? Well the Nacra F18 has tall bows the nacra 580 doesn't. At least not more then its predessor 5.8 and other nacra boats of that time frame.


Quote

and a super-cool ultra thin walled
chromium-alloy (chromolly) super strong and lightweight mast that
has better flex characteristics than other current aluminum or
carbon fiber masts.



Right ! All other designers are still using wooden masts on their boats right ? And clearly carbon wing masts are inferiour to this pretty standard tear drop shaped mast. Talking up your product is one thing but still is more then a little over the top is it not ?


Quote

The centerboards are high aspect ratio


The N580 centreboards have an aspect ratio of 2 (the width fits 2 times in the wetted length); see provide pics.

As comparison :

F18's daggers aspect ratio are between 3 and 4. Nearly double that of the N580.
A-cats daggers are close to ratio of 4.
Even the old Nacra 5.8 (predessor) had a daggerboard aspect ratio of 2.4 = 20 % more then the new one.

But we call these new dagger "high aspect ratio" !


Quote

When the boards are lifted half way up, they
swing so far aft that the center of lateral resistance is moved
significanlty aft and thus provides a superior resistance to
broaching.



Please all catamaran sailors that suffer broaching on their boat raise their hands.

No-one ?

Ofcourse broaching is a monohull problem. It is linked to the heeling of the boat and the weatherhelm that is caused by the centre of effort being suddenly moved far out of line to the single daggerboard as a result.

I rest my case now.

Wouter

Last edited by Wouter; 03/14/06 06:20 AM.

Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
Re: Blade F18 video [Re: Wouter] #68852
03/14/06 03:37 AM
03/14/06 03:37 AM
Joined: May 2003
Posts: 4,451
West coast of Norway
Rolf_Nilsen Offline
Carpal Tunnel
Rolf_Nilsen  Offline
Carpal Tunnel

Joined: May 2003
Posts: 4,451
West coast of Norway
Wouter, I think the key here is "Check out my April Fools Post from 2003:".


Re: Blade F18 video [Re: Wouter] #68853
03/14/06 05:00 AM
03/14/06 05:00 AM
Joined: Dec 2005
Posts: 55
Los Angeles, CA
chrisun Offline
journeyman
chrisun  Offline
journeyman

Joined: Dec 2005
Posts: 55
Los Angeles, CA
Quote


Pardon my french here...

...I rest my case now.

Wouter


Nice one Wout. Way to see the forest for the trees.


C-Class USA75
Re: Blade F18 video [Re: Rolf_Nilsen] #68854
03/14/06 06:51 AM
03/14/06 06:51 AM
Joined: Jun 2001
Posts: 12,310
South Carolina
Jake Offline
Carpal Tunnel
Jake  Offline
Carpal Tunnel

Joined: Jun 2001
Posts: 12,310
South Carolina
Do they have April Fool's Day over yonder? (April 1st - a day for jokes and hijinx)


Jake Kohl
Re: Blade F18 video [Re: Jake] #68855
03/14/06 07:54 AM
03/14/06 07:54 AM
Joined: Jul 2001
Posts: 364
Andrew Offline
enthusiast
Andrew  Offline
enthusiast

Joined: Jul 2001
Posts: 364
Quote
hijinx


haha, good one, Jake...


Andrew Tatton Nacra 20 "Wiggle Stick" #266 Nacra 18 Square #12
Re: Blade F18 video [Re: Rolf_Nilsen] #68856
03/14/06 08:15 AM
03/14/06 08:15 AM
Joined: Oct 2002
Posts: 1,226
Atlanta
bvining Offline
veteran
bvining  Offline
veteran

Joined: Oct 2002
Posts: 1,226
Atlanta
Quote
That daggerboard is a bit to short with too long a chord for my taste.


agree with that


Re: Blade F18 video [Re: Wouter] #68857
03/14/06 08:18 AM
03/14/06 08:18 AM
Joined: Oct 2002
Posts: 1,226
Atlanta
bvining Offline
veteran
bvining  Offline
veteran

Joined: Oct 2002
Posts: 1,226
Atlanta
Quote
Pardon my french here but what a non-informative post that turned out to be



Lighten up, Francis.

Re: Blade F18 video [Re: Jake] #68858
03/14/06 12:27 PM
03/14/06 12:27 PM
Joined: May 2002
Posts: 3,114
BANNED
MauganN20 Offline
Carpal Tunnel
MauganN20  Offline
Carpal Tunnel

Joined: May 2002
Posts: 3,114
BANNED
Quote
Do they have April Fool's Day over yonder? (April 1st - a day for jokes and hijinx)


I just blew milkshake out my nose when I read that.

Jake owes me a new laptop keyboard now :P

Re: Blade F18 video [Re: MauganN20] #68859
03/14/06 03:21 PM
03/14/06 03:21 PM
Joined: Nov 2002
Posts: 612
Cape Town, South Africa
Steve_Kwiksilver Offline
addict
Steve_Kwiksilver  Offline
addict

Joined: Nov 2002
Posts: 612
Cape Town, South Africa
oh boy I`ve missed the forum for a while, but this one is much too good to miss.
Maugan, gotta meet you some day. Wouter too.
if laughter is food for the soul, my soul just gained a few pounds.

April Fools Post from 2003 ? [Re: hobiegary] #68860
03/14/06 03:34 PM
03/14/06 03:34 PM
Joined: Jun 2001
Posts: 9,582
North-West Europe
Wouter Offline OP
Carpal Tunnel
Wouter  Offline OP
Carpal Tunnel

Joined: Jun 2001
Posts: 9,582
North-West Europe


April Fools Post from 2003 ?!

Ahh darn !

I'm know to put my foot in my mouth from time to time, but this one beats all the rest I'm sure.


Hook, line and sinker guys, no doubt.

Yep we have april fools joke overhere as well so I should have know better.

Good one

Wouter


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands
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