View Full Version : ISonic 117 (2011) Fin question for Remi

12th October 2010, 11:24 AM
Hello Remi!

The 117 is deep Tuttle. Is there any problem, potential dommages or speed lost if I use Tuttle fins instead? What are the inconvenience, if any?

Also, in previous thread, the fin charts says 44 cm Deboichet R16 fin for 7.5m sail, what would you suggest about the fin stiffness? As I see on the Deboichet web site there's stifness option we could choose from as well as the Rake angle, what would you suggest?

I am 170 lbs or 77 kg.

Thanks a lot!

Chris Pressler
14th October 2010, 04:32 PM
Hi Peteless,
you can go with normal tuttle fin! Guess you are good in the choose of the size. I tested the board with 48 cm and 8,1, but would have wished to have a bit smaller sized fin around 46cm.
Choose the medium stiffness.

All the best,

15th October 2010, 08:49 AM
hello again, i've read in another forum that deep Tuttle box has been created for fins of 60 cm and longer, is this true?

If true, so why the iSonic 117 has a deep Tuttle box since the max size recommended fin is 48cm?

Is using a deep Tuttle fin instead of a Tuttle would have something to do in the board behavior?

Chris Pressler
15th October 2010, 05:31 PM
Hi Peteless,
you will not have any problems or loosing speed, when using tuttle fins in deep tuttle boxes so far the fin fits well. The fin is just lighter. In terms of finsizes and stiffness Remi will answer you for sure!

Hope it helps,

16th October 2010, 08:27 PM
as far as I read on the Deboichet site the stiffness choice is available only for R16 formula fins, not for the R16sl slalom fins (<60cm).
Am I wrong?

Chris, in what wind/water/sail condition you found the R16sl 48 too big?

17th October 2010, 01:24 PM
the deep tuttle was born with Formula boards when growing in width year by year.
55cm to 60cm was ok in normal tuttle boxes but longer sizes over 60cm started creating problems in the Formula boards.
I imagine the main reason for deep tuttle in Slalom boards is the lower weight compared to the normal tuttle box which has additional the two openings for screwing full laminated.
So dont worry to use up to 52cm normal tuttle! I never saw or heard about broken boxes except material defects.
BR pfaffi

Chris Pressler
17th October 2010, 09:25 PM
Hi Cholo,
I found it too big with 8,1 and 15 knots sideonshore conditions.

18th October 2010, 12:05 AM
I found now best combo (117W and Reflex 8.6) with 43,5cm S1 fin! (184cm 91kg)
Tried before 47,5cm and 45,5cm
For me to big and not fully releasing the board



18th October 2010, 10:57 AM
hello pfaffi, what is S1 fins, a new brand or custom made?

18th October 2010, 02:01 PM
at the moment custom production on specific request just for a view top (and PWA) racer.
see: http://www.pfaffi.at/pfaffi_fins/Home.html
I do it for fun from the scientific view and not so much from the loft style try and error.

19th October 2010, 03:52 AM
Hi Pfaffi,

you fins look interesting (and good!).

What's the reason for the tip shape?


4th November 2010, 03:18 PM
Hi Cholo!

Fins are designed to maximize lift by a minimum of drag. Out of this is the special Tip shape. Additional to reduce the twist by outline design and not only by twist reinforcement. The used laminar profile is one of the fastest and non critical. Find some lift/drag diagram and profile views on my starting page.


Cheers pfaffi

4th November 2010, 09:09 PM
Tested 117 w from 18 kts to 30 kts.I found out the following set ups were excellent:

18-23 kts. low chop 0.2 m -severne code red 8.3-deboichet silver select 44 cm deep tuttle
25-30 kts.moderate chop 0.5m-severne code red 7.0-maui techtonics 40 cm tuttle

I am 84 kg.Surprisingly the board did not feel big or heavy or uncontrollable at 30 kts.On the contrary it felt even better than IS 101.Strange...