roy-
my humblest apologies for my caustic (i re-read it this morning) posting…it had no place on a friendly forum like swaylocks where an open exchange of information is key…
after thirteen hours in the shaping room yesterday i was tired and out of sorts, not the frame of mind to be in when trying to make a point and be civil…
any disparaging remarks towards you were uncalled for, again i apologize…
jim
I don’t believe any of the defenses of the Starfin need be apologized for. Roy took simple reasons why the starfin works and then dismissed them because of vertical forces acting on the fin. I bit illogical to say something isn’t so because here is this other thing.
It’s nice to have a holistic perspective when designing things. It’s also nice to disagree respectfully. And yes, sometimes people tend to communicate differently behind a computer.
We all appreciate Roy’s different perspective that’s what Swaylocks is about. It’s also about getting along.
Lighten up; try to accept other’s ideas. You may learn something too.
ps. You’re probably the first person, Roy, to describe Ben Lexcen as a member of the so-called establishment or authority.
Your reference to Ben Lexcen and his credentials is just the old ‘argument from authority’ which is always fallacious. Try taking a basic course in logic.
Huh?
I think that was dismissing “argument from authority” as compared to “argument from facts and theory and logic”
Ben Lexcen has great hydrodynamic credentials - arguing that you should just accept his idea because it is his is arguing from authority, which has its pitfalls. Just because some of Ben Lexcen’s ideas are terrific doesn’t imply all of his ideas are.
However, my “proof is in the pudding” argument was more that the Starfin receives excellent reviews from surfers of all walks of life, including some of the world’s best. I had not heard that it had problems of the sort Roy described (and still haven’t). That is arguing based on “empirical evidence”, which Roy dismissed out of hand based on his own experiences of some sort he didn’t really qualify or explain.
I’d still be interested to hear what experiences you had, Roy, that imply that tip eddies are a problem on horizontally oriented finlets.
Good words, Rob!
Roy… basic courses in logic teach that the so-called “argument from authority” is not always logically fallacious, since the strength of the support is contingient upon the quality of the authority in question.
In reality, there are many people who know far more than we do. Pointing to such legitimate sources does not necessarily invalidate the referrer, or the authority.
That fact should be obvious to anyone who participates in Swaylocks.
rob-
thanks…
i wasn’t backing away from my defense of what i consider a great fin design, i stand by that as well as “if something works, all the contrary theory in the world doesn’t change the fact that it IS working” …
i regretted the TONE of my argument and my thinly veiled sarcasms directed at roy…i’m not a wise-ass, nor cruel (people who live in glass houses, etc.,etc.) and apologized for coming across just that way…
this has been a great thread, though…
jim
Hey Jim,
Passion is good. If you’re angry express it. Better things will come of that then stuffing it, unless you let you anger turn to distructiveness.
To all:
I appear here to make a few observations, not to take sides.
Anger disguised as comedy can be very enlightening.
I know that I reveal what I don’t know by everything I say.
When I play a master out as a fool my act is an excercize in self rightousness. It leaves me stuck in a ditch.
What I know is that I don’t know.
I learn about what I don’t know by failing.
Failure’s road leads to success.
Success is momentary, and happens in the shaping room for a few of us that are very fortunate.
The best part of life is the inclusive part.
The reason sea otters nap at high tide in the sun is because they have their act together.
Mahalo, Rich
P.S. Hey Mike, Thanks for the great job you’re doing here for all of us here ~ !Swaylocks Rocks!
Cool pic. Watched a swan fly this morning. Really noticed the same wing position as in the picture. Probably influended by Roy’s half-circle fins. Swans seem ungainly in flight; still beautiful.
Edit: Now I’ll have to watch Winged Migration again tonight. cool.
Hello Blakestah,
Regarding tip eddies, I didn't actually say that they were necessarily going to be a problem, rather that all fin tips produce tip eddies at times. I accept that wing tiplets will improve the situation regarding downwash and the theory behind it all makes sense. My point was rather thus rather academic, and I was actually (as you have accepted) really just pointing out that annular wings have zero tip eddies.
My objection to the 'proof is in the pudding' argument was not to say that practical results don't count, I was objecting because the contents of the pudding were not described at all. I was thus expected to take the 'proof is in the pudding' statement as an argument in itself. I agree that it is relevant that the star fin receives good reports. The Star fin is also set up a little differently from my flat plane hydrofoil fins which caused problems, so perhaps I am comparing 'apples and pears' to some extent.
Nevertheless a fin like the star fin which has a lot of wing area at the tip is definitely going to be harder to move from rail to rail than a conventional single fin, or a tunnel fin. Perhaps surfers like it that way, it is not for me to say, except that I prefer a board with free rail to rail roll characteristics.
Roy
Hi Dale,
Sorry to disagree, but it is always fallacious to use the argument from authority. The idea that credentials offer even the tiniest bit of support to a theory is and has always been, untrue. In other words, " The star fin must be good because Ben Lexcen designed it" is untrue. Whereas " The star fin is good because a lot of surfers like it" is a perfectly valid point.
Roy
No worries Jim, I think Halcyon’s right, it’s a good idea to express these feelings. It does clear the air which is necessary sometimes. Regards, Roy.
Roy,
As I said before… in reality, there are many people who know far more than we do. Pointing to such legitimate sources does not necessarily invalidate the referrer, or the authority.
That fact should be obvious to anyone who participates in Swaylocks.
To not recognize legitimate authority is foolish in the extreme. Especially true if that “authority” is a 10 foot closeout beach break wave!
But if you hold that all experience and knowledge are relative, personally subjective… then you are consistent.
In logic there are five conditions for a legitimate “appeal to authority”:
1)The authority must have competence in an area, not just glamour, prestige, rank or popularity.
2)The judgement must be within the authority’s field of competence
3)The authority must be interpreted correctly
4)Direct evidence must be available, at least in principle
5)A technique is needed to adjucate disagreements among equally qualified authorities.
In any case, I have no problem agreeing to disagree agreeably… no biggie! And if anyones curious, theres plenty of info on the internet from which to draw an accurate conclusion regarding the subject of logic.
pura vida
Hello Dale,
Even if the five criteria are met, the authority being appealed to can still be wrong. This shows that the ‘five criteria’ are really only a ‘rule of thumb’
Your statement that “to not recognise legitimate authority is foolish in the extreme” is absurd. The world is full of supposedly legitimate authorities who have opposing views.
The true seeker will always establish truth using first principles and personal experience, and will not even accept theories from his or her own teacher unless they are independently provable.
Regards, Roy
PS this does not mean that all knowledge is subjective.
Roy,
I agree. But note… I said “legitimate authorities”, not “supposedly legitimate”.
Speaking of the establishment of truth by means of first principles and personal experience… a 10 foot beach break closeout is an outstanding teacher! Wow! Pass or fail!
Ha ha!
Thanks again for sharing your wisdom.
Such warm and fuzzy thoughts.
Whos to say whats actually “good” or “bad”? How do you even know there`s any such things as “good” and “bad”?
In respect to surfing, surfing equipment (and life in general)?
Theres all manner of "legitimate authorities" who have contrasting opinions. Masses of "truth seekers" who arrive at opposing viewpoints through their experiences. Sober and altered. All it proves is nothing. The scientific method of first principle, the establishment of "truth" can only go so far. Because its limited by our core ability: human thought. Thoughts can`t be directly seen, held, weighed, measured, or quantified.
When you go surfing, are you riding a wave, or is it riding you? Some would say questions like this don`t even matter.
pardon my ignorance, but could someone post a pic. of a starfin, i didn’t see one in the archives. thanks
pardon my ignorance, but could someone post a pic. of a starfin, i didn't see one in the archives. thanks
It is basically an elliptical wing (Spitfire wing), if you split it at the last 2 inches, and form a Y - the two sides are 60-70 degrees from the main foil
much thanks blakestah and cheyne
Nice one Dale,
However deciding just what a ‘legitimate authority’ is, is just as problematic. Even if we have a reasonable set of rules for what constitutes a legitimate authority, when we apply the rule, we still have no guarantee that any such authority is correct. So we are back to square one.
Roy
Shorebreaks are certainly good teachers. Sometimes my board rides the wave better without me. On the day I broke my seventeen footer I actually lost the board way out the back and it surfed the wave all the way in to the shorebreak on it’s own.
Fins are a drag.
