A new Paulownia shortboard singlefin

[Roy Stewart]

Just finished :





More pictures over here:




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[TReMoR]

wow! thats amazing!! how long did it take?

[Roy Stewart]

Thanks TReMoR, from start to finish was 8 months, as I had other boards to do so it just pottered along at a leisurely pace. I'm not exactly sure in terms of hours, about 100 hours or so.

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[RJD]

Given up trying to make a noserider ay?

[Hang11]

That's gorgeous. What's the deal with the fin - never seen one like it before?

[Roy Stewart]

Thanks Hang 11

The fin is a 'Spitfire' fin, based on the wing of the Spitfire WW2 fighter plane. We were the first to apply these fins to surfboards in 1995, and advertised them as Spitfire fins. Now there is another company ( Revolution surf) doing Spitfire fins, but we were the first by 11 years.

The story with the Spitfire fin is that it has the lowest induced drag of any fin or wing planform, essentially this means that it has less tip vorteces and a better lift/drag ratio than other shapes. It is the fastest most efficient flat plane non twisting wing planform possible.

It is interesting to note the turning characteristics of the spitfire compared with its rival the Messerschmitt 109. The ME109 with its narrower linearly tapered wing had a tighter turning radius than the spitfire, but the spitfire had a higher turn rate. In other words the spitfire could maintain such a high speed during the turn that it would complete a 360 degree turn before the ME 109 even though it travelled through a larger turning radius. The closest surfboard fin to the ME109 fin is probably the wavegrinder.

Another characteristic of this fin other than low drag and its ability to maintain high speed through turns is its benign stall characteristics . When the Spitfire fin starts to stall it does so first near the base of the fin, this makes the onset of the stall predictable and the stall easier to avoid. In comparison the linearly tapering wing like the ME109 or the wavegrinder will give less warning of the impending stall and will basically spin out suddenly and without warning. The spitfire fin does have a higher stall speed though.

The characteristics of elliptical planform fins were predicted by the classical lifting-line theory developed
by Ludwig Prandtl and published in 1918.

"The first closed-form solution to be obtained from lifting-line theory showed that in-
duced drag could be minimized by using an
untwisted wing of elliptic planform.

The classical lifting-line theory developed
by Ludwig Prandtl and published in 1918 was
the first analytical method to satisfactorily pre-
dict the performance of a lifting wing. Moreover,
until the development of the digital computer
in the early 1960s, it was the only analytical
tool available for wing design. Early compar-
isons between results predicted from lifting-line
theory and experimental data showed remark-
able agreement. Even with modern computa-
tional fluid dynamics (CFD) , it is difficult to im-
prove on the induced drag predictions derived
from lifting-line theory."

http://209.85.173.104/search?q=cache:fe ... cd=1&gl=nz

Bottom line is that they are a very fast fin, with a high speed turning capability and a high turn rate.

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[oldgrom]

AWESOME !!!!!!!!!!!!!! Absolutly AWESOME !!!!!!! LOVE IT !!!!!!!!! OMG BEAUTIFULL!!!!!! A true looker, fantastic work !!! Hands down get's my vote for one of the best !!! I gotta say some of the nicest I've seen !!! Love the WW II fin who don't love them WW II planes and the spitfire was one of the greats UK had to offer durring that time and love the hydronamic explanation of it's foil as for a log/wood it looks to be in the perfect shape (old school fin) which works great. Sheazz can't take my eyes off it.... Gotta love them woody's, just on looks alone,,, and yours are looking great !!!!!! Fine work... fine indeed !!

[Roy Stewart]

Oldgrom I confess to goggling at the pictures a bit myself, quite stoked as the board took so long to make and was justy a dusty forlorn object on a stand in the corner for months, thanks for the good vibes.

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[oldgrom]

Love that enormus tunnel tube fin too. Trust me I build surfboards and RC and custom furniture/homes and have gunsmithed for many many years and look at that board/boards created and just smile truly a art piece!!!, ha ha that works and you can use it!!!. Oh man the talk and conversation that thing would have with my buds while drinking down some pints!!!! Thaks for the good vibes ????!!!!! Anybody saying any negitive jiz about it ...well sir they have thier head firmly up their arse. I have balsa and will make a balsa one myself just havent done it yet but after seeing your beautifull working art pieces .... I am mor than just inspired. Ive allready tabed all my surf bro's to look at these gorgeuos baby's,one bud allready responded to me and said it looks so good he can't believe it took as long as it did "that thing is so cool and the lines are perfect allover it must have taken a year to do" "How do I get one?" ha ha ME TOO!!!
Good Sir those board creations have the honor of history and the beauty to where they can sit with the very best of the wood boards ever!!!!! and will allways outclass any foam/glass board!!!!!! Can't prais those sweety's enough all I can say is you must have been visited by some Hawaiian surf gods in your sleep,,, and you put a killer UK original twist to it with that Spitfire fin... To cool man,,, I'm gonna enter your stuff in a custom competition/display here in the U.S. Soyou might be getting a few more contacts!!! MAN O MAN hate to see what you'll do if ya got 5 or 6 months of dedicated time!!! ha ha keep it up and show that lovely off!!

[Phil]

hi roy how are things? love the boards, but being that i am a true longboarder and that longboarding is all about nose riding i was wondering how well your boards nose ride?

[Roy Stewart]

Hi Oldgrom I'm really happy that you are getting a kick out of the boards, they are a lot of fun to make I think you'll find that the building method we use is quite fascinating and easy too just very time consuming. It's been an interesting ride over the past 15 years making these boards ever since the first inspiration, lots of stories to tell !
I firmly believe that the the old surfers who have passed on are still with us, and if we tune in sometimes we become aware of their presence, I notice this when riding very big boards on really pristine days, and when designing and building boards.
On the wood work side of things mostly I just use bandsawn wood not thicknessed, and I'm relaxed about width of glue joints and so on, to me the resin is part of the medium so I just let it be rather than hiding it. This possibly comes from years of making boards on the road and out of doors with handtools.
Your stoke has come at a good time, it's been a long winter and it's always nice to get a dose of enthusiasm

[Roy Stewart]

hi roy how are things? love the boards, but being that i am a true longboarder and that longboarding is all about nose riding i was wondering how well your boards nose ride?

Hi Phil,

Thanks, I haven't built a noserider yet although I did design one for a guy a while back. I think that the parallel profile system has interesting possibilities for a noserider, maybe I'll dial one up soon but it's not my habit to walk the nose so someone else will have to try it out

To me longboarding isn't just about noseriding, I see noseriding as a recent trend and somrthing that really only applies to shorter boards under 12 feet.

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