National 12
Sidebar
 

T foil rudder conversion on a Winder Foolish

Started by ifoxwell, 25 Mar 2011, 10:12

« previous - next »

andymck

Steve

Toms system has the rope held in the slot, so it cant come out, then a control to tension up the system, so the jibsheets then work as ours do. The system allows the board to kick up about 1/3 if you run aground. You dont have the leeward mark issue, as the rope is always in the control slot on the board. It appeared very simple, and well sorted when I looked. Mine is currently in for repair of the trailing edge, and conversion to the new system. I will take some pics when the boat is back.

Andy
Andy Mck<br />3529

ifoxwell

Quote from: Steve (Guest)I have the trim tab centreboard and I would agree with Andy on the damage and the light airs issue. In the right conditions (medium wind strengths) I feel it does give a bit of a benefit. 
Getting the board down at the leeward mark is an issue with the system I have, so I was considering making some changes. I wasn't aware that Tom had fitted a different system to his. Maybe Andy or Tom could enlighten me about the details.

Steve
N3531


Hi Steve

So if its only really of benefit in medium winds do you find it a hindrance  at other times or just no different?

Ian

Martin (Guest)

Trust me...I have raced against Steve at our club, and he can make his dcb go in all conditions.
I normally need binoculars to see his transom!!! :(
 

Steve (Guest)

Ian,
The centreboard has a cap that can be put over the top, which locks the trim tab in line with the rest of the centreboard. In that mode the only difference to a normal centreboard is that the join between the trim tab and the centreboard is not absolutely smooth as it is with a single piece centreboard. The problem I find in light airs is spotting the transition and knowing when to lock it/unlock it. when it gets to about force 5 or more I don't think it makes much difference and we usually leave it locked and concentrate on other things like keeping the boat upright.

Steve
N3531

Steve (Guest)

Andy,
Thanks, some pictures would be handy when you get the boat back. I was thinking of 2 possibilities. One sounds simila,r which was to combine the trim tab ropes with a downhaul control line and the other was to add some "wings" to the top of the trim tab and permanently attaching the control lines to the trim tab wing ends then running the line straight to the forward turning blocks. The line would automatically tension when the board was fully down. One problem would be that the jib sheet tension would tend to pull the centreboard up. Maybe a downhaul rope is required for that as well.

Steve
N3531

grazz

Steve,

I thought through loads of options before making the system for the Very Hungry Caterpillar. My main aim was to have a system that was good around the cans for pond \\ river racing so it just needed to look after itself.
We have some "ears" on the head of the centre board with tiny pulleys at the trailing edge. There are trim tab control lines that attach to the trailing edge, go around the pulley and up to another pulley at the foot of the mast then cross over and onto the helms toe strap on the other side. 
There is then a cheeky spring bar which encourages the trim tab to stay on the side you left it, handy if you have to stop hiking.
The final piece is a cunning clip to lock the trim tab in the centre when the board is raised. The clip has elastic attached so when you raise the board the clip in engages and centres the trim tab.
It took a bit of tuning to get the forces and friction right but seems to work pretty well now.

I guess pictures might help, alternatively you're welcome to have a nose around
Happy sailing
Graham

Steve (Guest)

Graham,
Pictures woud be great if you could post some as I'm struggling to visualise the details from the description. Having an automatic system that just operates with putting the plate down is the aim.

Regards,

Steve

grazz

Steve,
Here's a picture of the assembly. There are control ropes travelling up inside the black "ears" which turn around small pulleys and attach into the trim tab (you can just see the pin and split rings that secure the pulleys). The other end of the control ropes turn around a pulley attached to the mast foot then go back to the helm's toe straps.
When the board is raised the semi-circular clip engages as the top pulls against an elastic loop attached at the base of the thwart and located into the groove in the clip.
I'm not sure if it makes sense from the photo.
Graham

andymck

Steve
Just go my boat back, most of the rope is under the kick bars.
Best have a look at either mine or toms



Andy
Andy Mck<br />3529

Steve (Guest)

Graham,
Thanks for the picture at least I can see it now. I don't claim to fully understand it yet, but as Andy says probably best to have a look at the alternative arrangements first.

Regards,

Steve