Carrying on from my 'Class 5 Set up issues' thread....
thought you all would be interested in the feed back from setting up my old class 5.
I still have a light front wheel even with 2.5kg of lead over it. And sitting up and shifting my weight forward going into the luff turn with a sheeted in sail. I'm thinking that I need to sheet in even harder. Which means I either need to remove my head when I go sailing so the boom can make its way to the other side or... I have to stand the mast up some more. Which is going to change the CofE! I think that to avoid this if I put a rollock on the end of my boom it will force more bend into the mast and flatten out the sail more and earlier. Currently the boom pushed beyond the mast to one side when max sheet is applied. What do you guys think?
See video for help. 20 > 26knts wind.
My 5 suffers from the same problem, I had to move my weight forward to be able to get around corners in anything like 20kns wind (I can move the steering back for light wind days). It was downright dangerous at Lake Wallyungup as there was a real danger of entering outcrops. I have a R&J sail to that I sheet in real hard maybe the foot is cut higher at the back of my sail that your sail. Just clears my helmet.
I would love to remove the rowlock from my boom but the distance is to short between markers at our site and it is difficult to hold the boom across and set up for the next turn.
I now have a 4.5 meter sail for strong winds
I get the same problem or worse. Last time in 20+knots the wheel lifted a good(
) 3-400mm. 5.5m2 R+J sail. The advice I've been given is 1) more mast rake as the wind speed gets faster, 2) sit up or move weight forward into the turn, 3) sheet in hard as possible as sail flapping moves the front wheel, 4) down on sail size - most of which you are already doing
I have noticed that if I swap from my R+J sail to my converted windsurf sail which though it's the same area it's only got 4 battens and doesn't cause anywhere near the same problem so I'm going for a forward shift of the bodywork and a cut down sail till my skill levels match my aspirations
Cheers Col
If you look at a lot of the french yacht video, they hold there boom across so that the front of the boom is on the right side of the sail. Pic below shows one with rubber attached to the end of the boom to make this easier.
My 4.5m sail is the same height as my R&J but is cut narrower at the back
To me it looks like you are still not sheeting in hard enough when you hit the turn. You may need to get another pulley ratio on the mainsheet. I have triple blocks top and bottom and still tie the tail end down to the floor of the seat giving me a 7:1 ratio. You will also need to get the boom a bit higher for headroom. Can you get the sail further up the mast? Shortening the top shackle and the one on the boom or make a different shape crane? Also I would rake the mast a bit forward. When you get that sail sheeted in harder it will come back to the same position of COE. Also when you come into the turn slide down into the seat with knees bent to get your head down lower. The flatter the sail is the less drag there is on it and the quicker it will flick over to the other tack. It scares the hell out of me every time. I guess that why we do it.
You can see the shape of the airtrack sail better in this pic
I have moved the block back 200mm since this pic was taken.
Thanks for suggestions, they all sound good.
I was thinking that as my yacht has the ability to adjust the angle of the front wheel beam relative to the tub and rear axles. If I raise the tub and there by raking the mast back more I can then stand the mast back up to where it was and gain some boom height. Enabling me to crank in the sail more and still keep my head. Pictures may help with my poor description!
I suspect you will need to rake your mast back AND drop the back of your seat, lots. Its a strange sensation that we dont need to do on our hard surface , but it seemed the way on the beach
Are OK thanks. Too me, as a sailor, that looks like how you would hook up the leech of your sail and get better pointing by centering the main sail without oversheeting and flattening the sail and loosing power. I'm not sure how moving the (gooseneck) boom end to the new tack makes a difference?
But looking at the French Airtrack sails they look like they have a much higher sail foot angle. Which I think could be the most important thing to change on my sail. My boom looks longer too. Or my tub shorter as those guys heads seem to be behind the boom when fully sheeted?
EDIT: I can't see any device in that video that stops the boom from going below eye line (and or) 45cm from the ground, as the FISLY rule stipulates.
I've changed the front main beam angle and added a Rowlock, and booked in my sail with the sail doctor to reprofile the foot a little. Now I need to wait untill October to get a sail in to test it!
to get that amount of sheet on with the old sail shape this is where the boom would be....
Thanks US772... I am a short (5'4") 75kg ( sorry for mixing imperial and metric! )
I can confirm a huge improvement! I have control in 20>25knts! One interesting thing was that with the 90Ëš on shore breeze one direction the yacht was 100% balanced with feet off the pedals the other way it would bear off quite hard. I think it might be the gradient of the beach... but it was bearing off up the gradient? I suppose also one of my wheel angles may have slipped earlier in the day. I noticed it later on.
I also found really giving it the beans going into the tack helped kick the back out more which in turn stuck the yacht though the wind much quicker. I still at time lost a little traction on the nose wheel meaning the exit was wider than I would have liked but 200% better than before. The front turning axle bolt was found to be lose at the end of the day too, so this may have contributed to lower front end traction? It needs a split pin to stop the nut working lose.
I'll post a video in a bit.
video:
does suspension make much of a difference to control? Those who have it... what was your yacht like before and after?
Ooooo.... I see. I like that idea of creeping up in the gusts!
I was thinking either the suspension system pictured or the type AUS230 has put on his yacht. Do they end up doing the same job or is one better at one thing or another?
If you scroll beyond the Standart I turn the camera around to face me and you can see the boom height and relative boom position through the tacks gybe's etc...
I am very happy with the setup on aus230. Mainly fitted it to stop sail shake. The system is adjustable but I could not comment if one idea is better or worse than another. I think Clems system would be much easier to fit as it does not require a major rebuild to the frame.
If you fit a suspension system that is behind the steering pin then the suspension
will affect the steering by an amount that depends on how behind the steering pin it is Hope this makes sense
In other words if the steering pin is rocking forward and back then the wheel will be tending to wobble from side to side if the foot pedals are stationary
Having the suspension right back at the mast this is negligible or alternatively springing the forks will stop this wobble also as they are in front of the steering pin
Having the steering pin rocking forward and back is also altering the steering caster geometry Thats my thoughts anyway
