VANCOUVER ISLAND WINDTALK • Evo fin box placement
Page 1 of 1

Evo fin box placement

Posted: Thu Jun 16, 2011 8:40 am
by eastside
Anybody have a Starboard Evo 80 ? I (Aftanas Surfboards) am converting my Evil Twin to a quad plus adding a single fin box so I need to know how far from the tail to put the single fin box. BWD kindly gave me some measurements and pics for the "thrusters" from his new 77 SB quad so I think I have that dialed.

Posted: Tue Jul 12, 2011 8:49 am
by ~~~~~4j~~
Have you finished this project yet? If so, how is it working? I'm tempted to experiment with this on my old RRD which is flat rockered. I'm interested to see how the "forward additional ailerons" affect peformance, especially turning. When you have a chance please post an update on your FAA-Quad, including what kind of fin system you used, symmetrical or asym fins, toe-in angles, measurements, etc. Or we can just discuss it at the beach. Thanks!

Re: Evo fin box placement

Posted: Tue Jul 12, 2011 11:08 am
by KUS
eastside wrote:Anybody have a Starboard Evo 80 ? .
yes, in my garage ...at your convenience. 8)

Posted: Tue Jul 12, 2011 11:11 pm
by eastside
The project is on hold due to the Chinook fin box getting held up by the mail strike and then me needing the board. Stefan is using a new stronger FCS fin box which he says is strong. Starboard doesn't have toe in so I don't plan on doing it. You can cant the Probox system but Stefan seemed more familiar with the FCS so I thought I would go with that system as SB is not canted. We are using the measurements from Big wave Dave's 77 L. I obtained some measurements of the single fin placement on the Evo IQ. Starboard uses symmetrical fins for the forward fins on the 2009 quad. They are FCS type fins. Most of the smaller thruster type fins are asymmetrical. SB had 10 and 11 cm surfinz (compatible with FCS). I have the 11 cm ones but want to try some smaller ones. At least the fcs type fins are relatively cheap. So I will likely try the asymmetrical ones. I will have to check out some of the surf shops and the internet. Any ideas? Will probably need some smaller 14 or 15 cm twin fins now so if anybody has some to sell pm me. Now I need 14 days of 25 knot winds to test it. The permutations of all the fin combinations is mind boggling.

Posted: Wed Jul 13, 2011 10:44 am
by winddoctor
eastside wrote:...Starboard doesn't have toe in so I don't plan on doing it.
There are threads in the Boards windsurfing forums that suggest at least some toe-in is a good idea despite a number of production manufacturers not having toe in for the front fins. The threads get into the reasons why toe in is better and also where to position the front cluster in relation to the back. Lots of guys have been experimenting with different fin set ups and have come up with good working after-market systems to convert a twin to quad.

http://boards.mpora.com/forums/quatro-q ... 56567.html

http://boards.mpora.com/forums/quad-con ... 53716.html

You need to wade through the usual BS, but some interesting stuff is buried in the pile...

quads

Posted: Fri Jul 15, 2011 3:40 pm
by wind-and-wave
Anybody know or try the 2010 starboard quad 86?

Posted: Fri Jul 15, 2011 11:52 pm
by nanmoo
I think Keen might own that one...

Posted: Sat Jul 16, 2011 8:39 am
by winddoctor
nanmoo wrote:I think Keen might own that one...
His is a 2011. Different set up.

Posted: Sat Jul 16, 2011 11:00 am
by eastside
Ok Winddoc. I will go with the toe in. Looks like 1.8 degrees is the number.

Wind and wave, I have a 71 L SB Quad 2010. Great board. Don't see why the 86 wouldn't be good for around here in all but the windiest of conditions. And if you get some 14 cm and maybe 13 cm fins then you can radically improve the high wind performance.

The upwind performance of the 71 got me on this conversion project of my Evil Twin 80. I used the twin a couple of times in Florence and once at Doug's Beach on my recent trip, so I haven't given up on the twin. You can crank turns better on the twin in the right conditions so I don't think there is anything magical about the quad. I want to try and make the twin more versatile at Columbia Beach on those gusty 5.0 days.

Posted: Sun Jul 17, 2011 8:19 pm
by ~~~~~4j~~
Thanks for the links Wdoc. I have been researching this quite a bit, and find that forum quite useful. You do have to wade through a lot of banter, but there is some good stuff there (and knowledgeable people!). The discussion can get quite in depth with lots of jargon. Someone appropriately posted this link to youtube. I'm leaning toward asym mini tuttle fins with a similar toe in. This way I can swap with my AHD.

On a related topic, I'd be interested in any feedback on how to make fibreglas copies of fins from a mold: I was thinking of something like this. I think this would be strong enough for small fins.

Eastside, I'm looking forward to seeing your project progress. Please post photos to keep us updated!