Fin areas??

ben.eliyahu.tom · Joined: 31 Dec 2013 Posts: 36

hey guys and gals, I am hoping someone here can help me... I recently purchased a 2012 Starboard Quad IQ 74L and would like to know what the fin area is for the 2x11cm and 2x13cm Drake Natural Wave fins supplied with the board is. I would like to get the most possible range out of this board and without knowing the fin area I unfortunately have no starting point to add or subtract fin area from. Starboard has been pretty shitty about answering this inquiry and I was wondering if anybody here has an idea? suggestions pertaining to fin combinations used, their positioning on this board, and technique modifications going from a single fin to a quad would be greatly appreciated as well!
Cheers, Tom

xander.arch · Joined: 23 Apr 2009 Posts: 217

Let me know if the data isn't available and I can help. You will need to very carefully trace the outline with a black pen pointing the tip inwards so that it actually follows the fins curvature and send me the scan. I will then put the scan into my magical mix of presto chango raster to vector area software. In other words, I'm an architect and work is a little slow this week so this is a pretty easy exercise.

Arrgh · Joined: 05 May 1998 Posts: 864 Location: Rio

Sounds easier than counting squares on graph paper. I find it odd that even some after market fin makers don't list area on their websites. I was looking at a JP fin that was for sale and found this on their website. I don't know how good their new fins are but they certainly aren't stingy with information.
http://jp-australia.com/2013/products/fins/freestyle-wave/ (click on board/fin combination chart)

U2U2U2 · Posted: Wed Mar 19, 2014 11:48 am Post subject:

Draw fin outline on paper.

From the base draw parallel lines across side to side .5 cm apart

Measure line distance edge to edge in mm , with ruler or digital caliper.

ADD up all line lengths. This example 237.45, divide by 2 = 118.725

thats the area is square cm. Written 118.725 cm2

From fins that have a published area that I have done for comparison its damn close. Formula came from Maui ULTRA fin, MUF.

they are way smarter than me.

For small quad fins, you can do this while the commercials are on while watching Dancing With The Stars .

wdsurf · Joined: 22 May 1999 Posts: 335

try black project fins.i think they have production board charts for fins/sails/board volume Question

swchandler · Joined: 08 Nov 1993 Posts: 10588

For windsurfing fins, you might consider True Ames. They identify the area of their fins. For example, the following information covers their Enduro model.

http://trueames.com/shop/enduro-wind-surf-fin

U2U2U2 · Posted: Wed Mar 19, 2014 2:35 pm Post subject:

think a couple posts are missing the question ;

The OP want to know what the area is on his existing fins, probably to get fins that are larger or smaller in area.

Once he knows that then lots of companies quote the area, but not all.

ones I remember

K4, Maui Ultra Fin, True Ames, Makani

ben.eliyahu.tom · Joined: 31 Dec 2013 Posts: 36

thanks for all of the responses so far, I will trace out the fins tonight and send them to xander.arch. I'll also try out U2U2U2's method as it looks pretty cool and lets see how well these methods work, I think if they are within 5% of each other the average should be a pretty darn good idea of what the actual area is. I do really like the lines method though as you can easily calculate how much area is placed in which part of the fin. if we can get some sort of database out about these specs I think it could really help shed some light on what characteristics fin shapes have and what works for everybody. obviously looking only at area and where its placed is an over simplification but it could be a good starting point! so, measure out your fins people and post it here with a comment on sail sizes used and your weight and all that fun stuff?? Cool

ben.eliyahu.tom · Joined: 31 Dec 2013 Posts: 36

U2U2U2 · Posted: Wed Mar 19, 2014 3:18 pm Post subject:

I have a lot of BPF, they are very efficient , they 'tend' to run streamlined in relation to some, so the area is smaller VS the length compared to others.

They are really jewels, well made ,fast .

I have some of the first QUAD , Drake fins from Starboard, they are nice.

K4 have now large range of fins most all are multi fin, they are really sweet, the Graham Ezzy model is asymmetrical with built in toe, very reasonable in price, due to non G10 but NASA age plastic composite materials, available in most boxes, with areas published.

Which BPF did you order ? size ?