Trapezoid Keels

ghostshaper

Phil Edwards status
Jan 22, 2005
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The greenough stage 6 and hatchet fins sure look like rudders. A fin maker (already mentioned in this thread) who makes fins based on the fastest fishes in the ocean once said, "there's a reason why you don't see fins like this on a fish."

Back to trapezoids, you see these on airplanes, but not so much in the ocean. Not sure why, but I'd give them a try.
 

JDJ

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Mar 1, 2014
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MrSteve said:
Anyone try them? Cant figure if they'd have more drive, or be looser, just more dangerous to genitalia, or ???

Interesting looking fins, and maybe they work great. But those fins look like trouble. Would hate to take one to the ribs. Fins are dangerous enough already.
 

griffinsurfboard

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Oct 31, 2004
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I am referring to those show winning ones you posted not these Trapezoid ones .

These trapezoid fins will be very powerful but won't re enter as well as Keels with tapering tips + a few other things narrow tips add to a fins performance .

 

Duffy LaCoronilla

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Apr 27, 2016
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deforest said:
Best in Show 2011 at Del Mar Sacred Craft Expo.

Rear trailer quad fins.... look familiar?

http://dantomo.blogspot.com/2011/10/next-gen-wins-best-of-show.html


A fin setup so good that everyone is using it now....

It’s all see these days.
 

Havoc

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May 23, 2016
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Duffy said:
deforest said:
Best in Show 2011 at Del Mar Sacred Craft Expo.

Rear trailer quad fins.... look familiar?

http://dantomo.blogspot.com/2011/10/next-gen-wins-best-of-show.html


A fin setup so good that everyone is using it now....

It’s all see these days.
roy stewarts tunnel fin is a faster design
 

deforestcooper

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Nov 1, 2016
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Duffy said:
deforest said:
Looks like another attempt to replicate a Daniel Thomson/Mark Thomson fin design (IMO).
Lol.

https://trueames.wordpress.com/2012/09/06/greenough-surf-fins-history/

Here is a question for Duffy or Greg.

Can you guys see or guess who's initials are on the bottom of that board that Chuck Ames posted on his website?

Keep in mind that on Chuck Ames website he says in his "History of the stage 6 fin" timeline that in "1987 Greenough encourages 'CHUCK AMES' (emphasis added) to use the paddle fin design on surfboards. The result: A thruster setup with 3 small paddle fins, unfortunately they would break off since they were glassed on with and had a very small base."

In case you cant see... the initials on that board are "MT" because Mark Thomson shaped and glassed that board and fins. And I dont think Chuck has any first hand knowledge of how those fins worked or what broke or didnt break unless Greenough or MT told him. I think its missleading to say the least that Chuck Ames would put a picture of Mark Thomson's board and fins on his website then take credit for the thruster set up as his own. Not an accurate narrative to surf history at all.

 

xmesa

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Jul 25, 2014
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i have a set, they're weird. I'll loan em out to anyone local to o'side if you want to try em.

i bought a set of futures from Vulcan after surfing a Vulcan Tachyon. it was too big and boaty for me ... by a lot... but i had a few surprisingly good waves on the Tachyon

i need to read the thread to see if i have anything new to contribute but ...

the trapezoids do feel like they load-up and release the way the hatchets do, it's kind of trippy but fun once you get used to it, i expected them to feel super stiff and i was wrong.

they turn a lot more quickly than i expected them to. I've only ridden them a handful of times in a 5'0" fish in about head high waves. i need to surf them more before i can have much of an opinion.

They don't go from arc to pivot seemingly randomly the way the hatchets do.
I really like Thompson's hatchet keels in small waves a lot more than the quads.


 
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xmesa

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Jul 25, 2014
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i got the thompson keels because he and tomo were using 'em on a fish design a long time ago and just generally speaking i think having more fin surface area works on boards with wider tails... i dont have an HP twin to try the trap's out in.

i did not like the hatchet quads on HP boards. i don't like them on superchunk (pictured) if the waves have any size.

the hatchets (quad/tri) were super twitchy and unpredictable feeling in hp boards, maybe it takes a better surfer like tomo to appreciate.

i've been thinking about trying out just the hatchet trailer with my normal fins when the waves are weaker for the sake of experimentation... futures released a set like that awhile ago (vectors?)
 
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feralseppo

Billy Hamilton status
Feb 28, 2006
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i got the thompson keels because he and tomo were using 'em on a fish design a long time ago and just generally speaking i think having more fin surface area works on boards with wider tails... i dont have an HP twin to try the trap's out in.

i did not like the hatchet quads on HP boards. i don't like them on superchunk (pictured) if the waves have any size.

the hatchets (quad/tri) were super twitchy and unpredictable feeling in hp boards, maybe it takes a better surfer like tomo to appreciate.

i've been thinking about trying out just the hatchet trailer with my normal fins when the waves are weaker for the sake of experimentation... futures released a set like that awhile ago (vectors?)
Forestcrapper is going to send you death threats for not giving the "original" hatchet fins 5 stars and a happy face.
 

xmesa

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Jul 25, 2014
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^ if he's a true fan his rage will be offset by the fact i commissioned a drongo-fish copy and bought the fins from Mark... ( through @foamandfunction )

despite qualms about supporting someone who beats on women in the line up
 

teeroi

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Oct 21, 2007
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4FCB3A6A-5DF3-4868-9FCA-0B3A41A323EB.png

I have an HIC Eric Arakawa Wombat. It’s a double wing swallow fish style board but thruster. Haven’t ridden it in awhile but it’s fast and fun. I was having issues surfing it vertically cause it’s flat and has a full outline. It was suggested by someone at HIC to try the hatchet trailer. That adjustment really helped. I remember I could almost hear the board fight going straight up after I squared up a bottom turn screaming go down the line stupid. But the short base helped the board pivot easier side fins being the same. Your mileage may vary.