Hey Bubble7777, I have about 5 tell-tales on the leech of the main that extend past the end of the sail. When the sail is set correctly, these little fellow stand straight out. If I bring the main in, they tend to fold back away from the centre line of the boat (for want of a better reference point) and if I ease the main too much then they tend to curl back in towards the centre line of the boat.

Its a bit like reading the luff on a head sail when you compare the tellt-ales on both side of the sail. But with having them on the leech of the main, the one tell tail in each location is influenced by air from both sides of the sail.

Disclaimer. Probably wrong again but works well on my boat. And beside, in any discussion "The Captain is always right"


One problem with boat that heave big overlapping head sails is that they are unable to read the Main Sail Luff due to the head sail influence. This is why you need to have the tell-tails on the leech to set the sail correctly.

Back to basics. The sail is a wing. Wings stall if the angle of attack is too great. So as the wind moves from a beating position to a reaching position, the sail needs to move too. Hence typically the boom and main sheet is eased out on a reach.

However, if you have a twist in the sail from top to bottom, the top of the sail will not be driving when the boom is eased out. I think this is what you are observing. The twist may be caused by a numer of things, but usually if you tighten the boom vang it straightens some of it out. A similar effect can be achieved by easing the traveller instead of the main sheet.

Finally got a great day. Sailing along on a beam reach from Hunter Island to Kepple.12 knots wind on the beam and sailing along at 9 knots. Champaign sailing, have a good day at work.

bubble7777 said..
thanks for everyones replies.

I played around with the sails yesterday on a 6 hour sail down to peel island in 18 = 25 knots I applied the boom vang and it made a big difference to the sail shape and the tel tails where streaming better. as the wind was so strong it was hard to tell if any trim was making much difference. there was still a need for much improvement but it was a step in the right direction.
.

Like I said, vang for sail shape, sheet and traveller for angle of attack.

Bubble,
Your boat is different. Its all about sail balance. A balanced rig, with neutral helm will sail fastest. A ketch without a mizzen, is going to tend to not have weather helm, but rather lee helm.

With the ketch rig, when the wind gets up, normally you would reef the main and carry on. In your case, reefing will tend to increase the lee helm. However, if you ease the boom vang, and let the top of the sail spill, the balance is better. Hence a looser vang may be the better solution in a heavy breeze. Letting out the traveller will still drive you faster if you can do it and not have a completely flapping sail.

However, in your typical 10 to 15 knot breeze, pulling the vang on and getting the right shape with the boom out, will no doubt be the most efficient solution.

HG02 said..
I think Ill add those tell tails Cursoe
Hes a couple of short articles
www.rya.org.uk/knowledge-advice/cruising-tips/Pages/hub.aspx

www.rya.org.uk/cruising/handling-sail/Pages/Trimmingthemainsail.aspx

those links are awesome hayden!.


also like a few mentioned the vang is important in upwind. letting it flop around seems to have been a mistake that contributed in part to my problem.

I just spent the last 3 days sailing and studying teltails and sail position and experimenting was a big part of the adventure.

my conclusion is that this stuff takes years to master. although little improvements along the way are nice :)

Hi bubble777. If you yacht was originally ketch rigged but has mizzen removed, if the main mast has not been moved aft to compensate or more correctly, to convert it to sloop rig, you are behind the eight ball and will always have trouble balancing the boat.

You might consider properly converting her to sloop rig as your next project. Fair few dollars involved as apart from the rig there will be some sail work involved too. Maybe the boat is ready for some new sails anyway.

Now THAT is a great conversion "before and after" shot on the mast position HG! Nice.
Edit: I should say a good explanation on the different mast positions for balance, but you know what I mean...:)

cisco said..
Hi bubble777. If you yacht was originally ketch rigged but has mizzen removed, if the main mast has not been moved aft to compensate or more correctly, to convert it to sloop rig, you are behind the eight ball and will always have trouble balancing the boat.

You might consider properly converting her to sloop rig as your next project. Fair few dollars involved as apart from the rig there will be some sail work involved too. Maybe the boat is ready for some new sails anyway.

Cisco,
If you look at the internal pics of the Walker cutter design, you will see that there is also a stainless steel post inside the cabin. Moving the mast will also entail moving the chain plates, so the whole deal is not easy. Bubble has some videos on Youtube of him sailing, and you can see that whilst there is some lee helm, it is not too bad. Guess that is the advantage of a long keel.