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Author Topic: Solweig cutter sail boat  (Read 2559 times)

john44

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Solweig cutter sail boat
« on: April 28, 2013, 12:06:30 PM »

Hi guys,
 I have just tried to sail my Solweig cutter sailboat,
and trying to control her was impossible
she just went where the wind took her. (Its a good job I fitted a motor)
I rigged her similar to my IOM yacht, with the foresail and main sails
attached to a sail arm to let them in and out.
Is it better to fix the front sails and just have the main sail operating,
or put the front sails on their own sail winch/arm and how far do the
front sails have to be set if they fixed.
I know for the IOM its 5 degrees for the foesail & 12 degrees for the
mainsail. But with this type of boat I havent got a clue.

john
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tigertiger

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Re: Solweig cutter sail boat
« Reply #1 on: April 28, 2013, 02:30:11 PM »


First thoughts.

Both sails on the same winch should be fine, if set up correctly.
This sounds like a sail issue. Check that neither jib nor main is sticking or jamming. It sounds like the jib may be jamming.
The sail sets sound about right, when fully hauled in. When fully let out are both sails at approx the same angle (approx 90 degrees).

Another problem could be if the winch is not powerful enough. Then the sails will be pulled all the way out by the wind, and she will try to just run with the wind.

One problem I did have once is the the tray, that had the winch mounted to it, had broken loose. Not immediately apparent, but when the winch was operated, the tray turned and the sails were not hauled in.
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rmaddock

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Re: Solweig cutter sail boat
« Reply #2 on: April 28, 2013, 03:21:57 PM »

When you say "where the wind took her" what do you mean?  was it always going into the wind?  Out of the wind?

Could be the rudder's too small to have authority.  Could be that the centre of effort of the sail plan is wrong.  If the CoE is too far forwards, she'll always be blown away from the wind and vice-versa.

However, try the obvious first, as suggested above.
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tigertiger

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Re: Solweig cutter sail boat
« Reply #3 on: April 28, 2013, 03:25:57 PM »

As @rmaddock mentions.
Rudder could well be the issue, if she is a converted static model, and the rudder has not been increased in size.
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Netleyned

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Re: Solweig cutter sail boat
« Reply #4 on: April 28, 2013, 03:36:11 PM »

Any chance of a photo showing rig and keel/rudder
The guesses then may be better informed.
Yachts like IOM's have evolved over the years
and mast position, rig percentage and keel/rudder
are pertinent to the hull design and class rules.
Probably will not work for a static conversion
if that is what you have.

Ned
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john44

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Re: Solweig cutter sail boat
« Reply #5 on: April 28, 2013, 08:04:10 PM »

Hi guys,
I scratch built the boat from a plan,for a RC model.
She is 36" long not counting the bowsprit.
She has an oversize rudder, but the rake of the mast
does seem a bit too forwards, but is as the plan stated.
so her COE could be wrong, see what you think
I will post photo,s of her tomorrow

john
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tigertiger

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Re: Solweig cutter sail boat
« Reply #6 on: April 28, 2013, 11:56:48 PM »


Asking again...

When you say "where the wind took her" what do you mean? 


Do you mean no real steering at all?
Or do you mean she had lots of lee helm or weather helm?
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john44

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Re: Solweig cutter sail boat
« Reply #7 on: April 29, 2013, 01:39:12 PM »

Hi tigertiger,
she would not sail on a lee helm(into the wind)she even went backwards.

john
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tigertiger

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Re: Solweig cutter sail boat
« Reply #8 on: April 29, 2013, 02:51:43 PM »

Lee Helm is the tendency of a sailboat to turn away from the wind while under sail. It is the opposite of Weather helm which is the tendency of a sailboat to "round up" into the wind. A boat with lee helm will be difficult to sail Close Hauled and tacking may be difficult. A little weather helm is OK.

You can adjust for lee/weather helm by canting the mast back/forward with the stay(s). Backwards to give weather helm, forwards for lee helm. Only a little tuning is needed.


A gaff rig will not sail as close to the wind as a bermuda rig, and so she will not perform into the wind anything like as well as your 1m. If you go head to wind and end up 'in irons' she will be pushed backwards by the wind.
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tigertiger

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Re: Solweig cutter sail boat
« Reply #9 on: April 29, 2013, 03:01:22 PM »

Looking at your pictures, I cannot see if the gooseneck is rigid in the up/down direction. It looks like it isn't.


If that is the case, do you have a kicking strap? It looks like there is a metal loop for one at the base of the mast. This will be required to hold the boom down, that will also help her sailing.


I think I can also make out a bowsie on a line from about the middle of the main boom back to the mast. Is there any chance of a close up picture of that to work out what it is?


Your mast does appear to be canted forwards, which will give you a lot of lee helm making her difficult to sail into wind. Try relaxing the forestay and tightening the two rear stays.


It could just be that the rigging needs a bit of tuning and bobs your uncle.
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rmaddock

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Re: Solweig cutter sail boat
« Reply #10 on: April 29, 2013, 04:04:11 PM »

Have you tried sailing it without the jib, but with only the stay sail on the front?  To my eye it looks like the mainsail is quite small.  This would make the rig's CoE too far forwards resulting in the behaviour you describe. 

The hull has a centre of balance and, when sailing (and in simple terms) it acts like a pivot.  If the effort of the sails is centred too far forwards of this point then you're pivoting the hull out of the wind.  Loosing the jib (foremost sail) would move the CoE backwards and might help.  A longer boom and bigger mainsail would do the same.
As Tigger says, a bit of weather helm is considered a good thing in real boats.  This is where the CoE of the sails is slightly behind the centre of the hull.  A gust of wind will, therefore, tend to turn the boat into the wind.  The worst that happens then is that you stall the sails and get embarrassed.  Lee helm has the boat being forced out of the wind which turns it sideways on and can cause a capsize.
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john44

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Re: Solweig cutter sail boat
« Reply #11 on: April 29, 2013, 05:52:21 PM »

Thanks for your imput lad,s, although the mast angle and positioning was exact to drawing
it did seem to lean forwards too mutch. I have removed the mast and made a pivot in it at the base
so I can adgust the mast forwards or back using the stays.
The bowsie in the boom was for adgusting the angle of the main sail.
The kicking strap was a chord fixed to the deck and the bottom of the boom.
but gertting back to my main question ,how far do the front sails have to come out?

john
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john44

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Re: Solweig cutter sail boat
« Reply #12 on: April 29, 2013, 06:45:50 PM »

tigertiger
the bowsie I think you were looking at in the middle of the boom is
for the clew/outhaul.
Would it be better to control the both front sails, fix the middle one,
,or fix them both at a set measurement?
If so what should the measurement be?fixed or controlled.

When the boat is on its waterline/in the water, should the mast be
exactly vertical. e.g. spirit level vertical I mean.
Once again thank you all for taking time to try and help me.

john
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tigertiger

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Re: Solweig cutter sail boat
« Reply #13 on: April 30, 2013, 09:56:09 AM »

Both front sails can be controlled, and should be otherwise she won't sail well.
All three sails can be controlled from one sail servo.
I would set it up so that each sail, going forward from aft to fore, should be a little bit further out than the one behind.


The angle of the mast relative to vertical is not important.
The angle should be one that allows the boat to sail with slight weather helm. If you boat has been built from a plan, the designer would have sorted out all of the important dynamic issues (CofE, CLR, etc.). If the sail plan (size and shape of sails and mast) is as shown in the plan, it should only be a matter of tuning the rigging.


Once you start to stray from the original plan, you risk compounding some problems and adding new ones to the mix.
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john44

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Re: Solweig cutter sail boat
« Reply #14 on: May 01, 2013, 12:12:27 PM »

Hi guys,
I did stray from the plan regarding the mast, it just looked wrong
and sailed like a log.
I have made the mast rake adjustable like my IOM and with pulling
the mast back, fitting a adjustable kicking strap, fitting more bowsies
to create more curve and also set the sails forward from aft as
tigertiger stated, well I took her to the lake and she sailed like a dream.
Thanks for everyone who helped me and thanks Martin for this
brilliant forum.

1 happy model sailboat captain

john
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rmaddock

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Re: Solweig cutter sail boat
« Reply #15 on: May 01, 2013, 09:12:45 PM »

Excellent  :-))
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