This contra -‘arguing from authority’
debate has been getting very trite:
I lump this in with the
'Dont believe everything you read ’ line
which someone will drag out when
they dont’ have anything else to void your
argument.
I think we all read, absorb from authority and use
our discernment, but dismissing authority out
of hand is the same as
‘dont believe everything you read’
Which gets you no where, and leads to these
tail-chasing threads!
You either get it or you don’t. If you are a mental purist then you will get it. And it is logically correct whether you think it is trite or not. Arguments from authority are always fallacious. I am not dismissing authoritative sources of information out of hand, I am merely pointing out that a theory is never true just because it comes from an authoritative source. If you wonder why I am persistently making this point then realise that it is because I have been hearing arguments from authority a lot recently and they always confuse an issue.
Roy
2 Points.
1)Actually, quite seriously and earnestly,I have
a reply to your previos post, but out of respect
for your authority and staying true to my words,I prefer not to engage in a little bit of chasing my own tail.
You either get it or you don’t. If you are a mental purist then you will get it. And it is logically correct whether you think it is trite or not. Arguments from authority are always fallacious. I am not dismissing authoritative sources of information out of hand, I am merely pointing out that a theory is never true just because it comes from an authoritative source. If you wonder why I am persistently making this point then realise that it is because I have been hearing arguments from authority a lot recently and they always confuse an issue.
Roy
Your penguin needs oxygen? 
Fascinating. Opinions, contentiousness, apologias, contrition, self flaggelations. And, roller coaster repeat. C’mon, syllogists, this is fuckin’ smegma. Everybody’s right, and nobody’s wrong (lyrical, eh?) LOL, read the thread title.
Ah, what the hell, carry on.
me like surf
Your penguin needs oxygen?
What? You dont respect your authority?
“They are the most intelligent people in the world who imagine they must personally experience, evaluate and verify all things in order to regard them as true. That, or they know absolutely nothing.”
Wilfrid Sellars
Why don’t you guys take all this cerebral stuff and start a thread with it?
Things have gone so far off on a tangent I don’t see how fin theory could ever get back in the circle this thread started in. As far as I’m concerned this thread is dead.
IMHO if you’re going to get into personal issues or develop you theories on authority you ought to do it somewhere that’s appropriate not on a thread that’s devoted to fin theory.
Try and stay on task. I know it’s hard but we are adults.
If you feel persecuted or have a problem with the way someone addresses you try using a personal message option on this site. It makes a hell of a lot more sense than clogging up a good discussion on a topic with a bunch of personal moments.
Cancel my subscription to this thread.
Gone Fishin’, Rich
Once upon a time there was a man called Galileo. He made fins which rotated around the sun. . . .
I think that in this same time, there was a man who wanted the sun to rotate around his own fins…
3 hours in Marid’s airport waiting for my plane to Portugal and i still don’t know when it will arrive here… The good think is that at least i know my board is already in Portugal, waiting for me.
Please guys, turn this thread back to the fins theory, i want to learn more.
Hi Rich,
tell us something about fins then. You are right that it got off on a tangent but that’s the way it is sometimes when one is trying to get to the bottom of things. Are you in a hurry or something? I am just defending the idea that basic principles are more fundamental than any “so and so is an expert so his fins must be good” nonsense. Here’s some fin theory for you. The tunnel fin may be tuned for tighter turning by shortening the length of the fin. A fin three inches long or less will turn very tightly. Also making a thicker fin will enable the foil to turn more tightly.
Roy
Why don’t our fins look more like windsurfing sails?
Hey Roy,
In the interest of courtesy I’ll answer your question.
Thanks for asking but frankly I don’t think I can tell you anything about fins. Secondly I don’t think we’ll every get to the bottom of things.
Am I in a hurry? well I have many things to do before I die and one of the most important of them is increasing my scope. I do that on my own terms, at my own peril and find nature as the ultimate authority.
When it comes to fin theory I prefer to maintain my humility and leave all the technical jargon to those who want to spend their time there.
Don’t expect me to get in a debate with you. I have better things to do. As far as the merits of you semicircular fin are concerned. I may be missing out on the best thing that has ever been developed in surfboard performance but when I look at the surfboards you’r3 riding and consider foiling and mounting the system the time investment for the return expected makes to project prohibitive. My intuition leads me in a completely different direction. You may go on tauting the design infinitum if you choose I just wont be on the bandwagon. It won’t serve my developmental process at this point and time.
The one thing that an arc on the bottom of a board has potential for is as a base for a hydrofoil like the one that Laird is riding where the board he’s staped to rides completely out of the water. The arched base might be a good way to mount the hydrofoil on if it’s foiled properly and it might be foiled to add lift to the system as well. One sure thing is that it would dampen vertical motion of the foil. It would also be very strong. However foiling one would be a nightmare unless it could be foiled and then flexed into the arc, which I can’t invision as a possiblity unless it was made of metal. I’ll see what Laird thinks (-;
Hey Rob,
How would you attach the sail outline to the board? The base only touches the board where it attaches to the mast. You can’t get enough structural integrity out of a slim vertical mount for it to hold up under the stresses of turning underwater. If you extend the base at the leading edge along the board bottom to get enough surface to mount it with the template would work. With the very wide tip area it would impede rail to rail transition though might be used with some success as a twin fin template or as a power single for big waves.
A similarly templated (Bottlenose) fin is attached.
Ask me why I choose the name.
Off to the fin shop, Rich
Here’s a glass and resin semi - bulb keel fin for a hybrid tunnel setup made for me by Chris Carr of ‘CC’ foils. I don’t work with glass myself but Chris did me a couple for Christmas. The second pic is of the panel for my new 13’9" Dragonboard fin.
Roy
Hi Halcyon
The wind surfer sail plan shape,these sails are meant to have minium distance between the water and the foot of the sail
Therfore effectivly the bottom of the sail would be in contact with the board if the template was used on a board
As for the tip are it would be good for providing lift but as you say a bit too much will stiffen up your board and a little too little will not produce enough lift and so just cause drag rather than function ,guess it finding the balence
Roy
I have a 42 foot yacht I designed and built myself, I have sailed it around the world, its very light, very flat, has water ballest, surfs ocean waves at speeds inxcess of 20 knots with no problem
It has twin semi balanced carbon rudders and a vertical small cord 3 meter deep keel with a bulb
But its a boat not a surfboard so I dont include it in these threads ,the boards that I think we in this thread have been talking about were mostly short boards 5 to 7 foot with the odd fun/mal to 9 foot
Maybe for your long speed boards fin setups you should have another thread cause what you use on a 17 footer is not going to do the same on my 6 footer
Looking forward to more relevent fin disscussion
Reagards Mike
Hello Mike,
That ocean surfing on your yacht must have been a blast! If you had been reading carefully you would know that I haven’t put tunnel fins on seventeen footers. The tunnel fin setups I have been discussing are presently, as I write, on a 7’5" , 9’1" , 9’6" , 10’4" , 11’8" , 11’9" , and 14’9". All these boards are successful easy to ride boards.
We are also in the process of building an 8’1" which will have a carbon fibre narrow based bulb tipped front fin and a six inch tunnel.
I have posted pictures of the 7’5" already.
I have also built various other flat plane and full circle winged fin boards at 6’1" , 8’5" , 9’1", 10"4" , and twelve feet.
Some of these boards tested many different winged fin prototypes, including twin in -line flat plane bulb tipped cruciform fins and hydrofoil double bottoms.
I hope that this information clarifies the situation regarding the relevancy of my fin designs for standard board lengths.
Roy
PS Perhaps if you prefer to discuss fins for boards in the five to seven foot range then you could start a new thread yourself. I have a 5’9" tunnel finned kneeboard spoon drawn up which will be started soon. It will be sporting a ten inch pure tunnel fin. So I will be active in discussions about fins for shortboards.
Ben Lexcen was a surfer and boat designer....he was into driving fast cars...
he was a great family man and loved his wife very much…he taught me so much about hydro-dynamics that has helped and is still helping the surfing world today.
Ben Used to go out in the rain as a kid with boats he had built and block the streets off so the water would build up and then race the boats down the street.
There was alot of time, testing and technology go into the Americas Cup and we were lucky to get a small piece of all that wisdom from someone who knows Ben Lexcen.
Hi Roy
Yes point taken
I think that the point you raise answers my sometimes frustrations with the threads
I feel that when disscussing fins maybe we need to first highlight which size boards
These threads quite offten seem to get very close to answering questions only to suddenly disapear of on another tangent
mike
Cheyne,
Everybody has a part to play in this world. Ben Lexcen was obviously a talented person. Thanks for telling us a little more about him.
Roy