Starboard Forums

Starboard Forums (
-   Free Forum (
-   -   Deboichet stiffnes index (

Expander 19th March 2007 08:56 PM

Deboichet stiffnes index

Dear All,

a simple question about Deboichet fins stiffness index:

how to interpret -- (minus, minus) signs ?

In other words, a S-- fin is stiffer or softer than a simple S one ?

Many thanks.

- Expander.

Remi 19th March 2007 09:14 PM

RE: Deboichet stiffnes index
Hi Expander,

A Soft -- is softer than the soft.

All the best

o2bnme 19th March 2007 09:49 PM

RE: Deboichet stiffnes index
I've never been clear on how to measure rake. Can you explain rake for me?

Remi 19th March 2007 10:54 PM

RE: Deboichet stiffnes index
Hi o2bnme,

3 Years ago their was only on rake, and Deboichet decide to mesure it like this :

From the original rake, you mesure at 68cm from the base and he reduce the angle by + 1 to + 12cm (vertical).

All the best

Expander 19th March 2007 10:57 PM

RE: Deboichet stiffnes index

Thank you, Remi, for very quick reply.

So, if suggested 161 fin (R19) with rake +8 and stiffness S-- should be used in light to medium wind (from 7 to 15 knots) and not over, I wonder if same fin rake +6 and stiffness S could be used from 15 to 20 knots.

R13, instead, could be used only over 20 knots.

In other words, what do you think of this 161 fins quiver:

from 7 to 15 knots: R19 +8 S--
from 15 to 20 knots: R19 +6 S
over 20 knots: R13 +6 M


Remi 20th March 2007 01:03 AM

RE: Deboichet stiffnes index
Hi Expander,

This is what I use right now :

Under 15 knots : R19 soft -- rake +8cm

Over I use R13 soft rake+ 8cm you accelerate more with the R13 profil in this condition compare to the R19. I prefer the soft one, you get more lift with it and very good also in extrem choppy water and waves.

The R13 medium rake +8cm, I like it also but from 16 to 20 in flat water, but with only 2 fins I am perfect.

All the best

Expander 20th March 2007 02:43 PM

RE: Deboichet stiffnes index

Thank you Remi for your infinite patience.

At this point I wonder what could be field of utilization of a R19 +6 S; in other words: when to use or who could use it?


- Exp.

Remi 20th March 2007 04:13 PM

RE: Deboichet stiffnes index
Hi Expander,

If you have to order it, go definitely to the R19 soft -- rake +8cm or 6cm but not the soft one, it's too stiff. It's not a bad fin but the soft -- is a lot beter under 15 knots. And over 15 knots the R13 profil is beter due to less drags.

All the best

G 23rd March 2007 04:58 PM

RE: Deboichet stiffnes index
Hi Remi,
what's the difference between R13S+8 and R17S+6 over 16 kns (on 161) ?
I find the R17 very fast in that condition but it put me in trouble when it gets lighter.No way to keep a good angle if not very good powered up from sail....
I think that the R17 should work fine since 13-14 kns to 25 kns (but with 11,0 or 10,7,not down) .
Just my 2 cents

Remi 23rd March 2007 05:08 PM

RE: Deboichet stiffnes index
Hi G,

You right for the R17 soft rake + 6cm, it's a fast fin in stable wind over 16 knots to 22 with a 11m particulary down wind, but prefer the R13 profil who give me a beter instant acceleration and angle and make an important difference in unstable wind condition and also on a start line.

All the best

All times are GMT +7. The time now is 11:35 PM.

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.