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Old 17th February 2007, 12:35 AM   #3
Roger
Dream Team - School Guru
 
Join Date: Aug 2006
Posts: 2,109
Default RE: Start centerboard?

Hi guys,
First, let's determione which Start center fins you have, how much water
depth you are teaching in, and what sort of "storage" problems longer center fins might create?
So, what color and shape are the center fins you are using?
This one......?
http://www.start-windsurfing.com/image/parts.jpeg
This one......?
http://2002.star-board.com/products/image/start_mn7.jpg
This early "Starbox" Retractable....?
http://2003.star-board.com/products/boards/star_box.gif
The first "Clipper Box" retractable....?
http://2004.star-board.com/products/image/clipperbox_blue.jpg

Depending on which you have, we have solutions for you (based on your available water depth).
I've used all the models of the Start boards to teach more than 1000 new windsurfers in the Starboard/Sailworks "A Taste of Windsurfing" program, and while I've not always agree with the philosopy and performance of the various center fins and centerboards *bd has supplied, we've always been able to come up with some alternative that worked and allowed our "fledgling" windsurfers to sail back upwind to where they started, once they get the their basic skills (uphauling, getting underway, tacking) mastered. Most of them have had no problems what so ever sailing back to where they left from on their very first time on a board.
There have been occasions where there were adverse, strong, sideshore currents where we were forced to use rather drastic "measures" (like tethers in the Hampton Roads main channel) to keep our students in the beginner area, but mostly we've been able to come up with fins that balance well with the board/rig and there are no problems staying upwind.
So, if you can identify which center fin/retractable centerboard "system" you have on your boards, we can offer some suggestions that we've found to work and solve any "downwind tendancies".
A couple of major variables here is where you place the mast foot, and
the sail sizes and rig types you are using.
For sails smaller than 3.0 m2 it's absolutely critical that the mast foot be as far back in the slot as possible.
This is a CLR (Center of Lateral Resistance) of the fin/centerfin vs the CE
(Center of Effort) issue and with the smaller sails, the CE is so close to the mast that there is really no way to get the CE to "balance" over the CLR (or better still behind it) with the distance from the Start mast base slot to the CLR of the center fin or center board.
I've tried numerous times to have a longer mast box insert put into the Start, Rio, and Starsurfer/Kiddy boards to solve this issue, but the problem remains.
So, I&#39;ve built a "mast box extender" that really does solve the problem and you could easily build the same device for your smallest sailors on < 3.0 m2 rigs.
An alternative would be to have a local board repair shop put a auxilliary mast box in some of your boards ( or do it yourself) for your tinyest sailors.
So, please reply as to which center fins you are using, and we can suggest what we have used that solves this problem.
There are also some "beginner technique" issues that we&#39;ve encountered and can offer some suggestions on this aspect as well.
Hope this helps,
Roger is offline   Reply With Quote