Mast rake advise needed

jfkal

jfkal

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I have a Jeanneau 36. Friend of mine now pointed out that the boat has a to big of a rake (taking a weighted halyard down lands about a foot aft.
Any ideas or comments whether this is a concern. Comparing with other Jeanneaus and Bennteaus it looks significant more as most of them are totally straight up.

Many thanks

Joerg
 
jfkal said:
I have a Jeanneau 36. Friend of mine now pointed out that the boat has a to big of a rake (taking a weighted halyard down lands about a foot aft.
Any ideas or comments whether this is a concern. Comparing with other Jeanneaus and Bennteaus it looks significant more as most of them are totally straight up.

Many thanks

Joerg
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Mast rake is the the angle between a vertical mast and a mast leaning backwards (as opposed to mast bend).
If the mast have changed it's rake it can be a sign that something have happened to the forestay.
When did you do a rig check last time?

If there is nothing wrong with the rig the mast might have been set with this rake on purpose.
Increasing mast rake (leaning the mast aft) will move the sail center aft, decreasing rake will move sail center forward.
So adjusting rake is used to change the balance while sailing (rudder used to keep the boat on track).

Before you start changing the rake you need to know what you will gain with doing so.
 
Unless your friend has the same boat or is very familiar with your model of boat (correctly set up), looking at the amount of mast rake is not a very useful way of deciding if there is too much or too little.

Better (as sailorman says) to judge it from how the helm feels when sailing upwind. Its common to set a boat up with just a touch of weatherhelm in order to give the helm some feel upwind. Some sailors prefer neutral helm. Lee helm is not usually desirable.

So, if your boat feels good on the helm upwind, leave the rake alone. If you feel like you have too much weatherhelm, move the rake forward a little and test again.
 
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I have a Jeanneau SO35 (2005) with in mast furling. It also has significant mast rake (about a foot). I have compared it with other SO35s boats with the same rig and it is same. Its always been like that since new. It is a Sparcraft mast.
 
Thanks for all your replies. Some rake was there from the time I bought her. Then someone commented on a too loose forestay. More oompf on the back sorted that out. Boat balanced fine until I got my new main. Now the weather helm is very strong. So guess I nudge the mast up a little.
 
jfkal said:
Thanks for all your replies. Some rake was there from the time I bought her. Then someone commented on a too loose forestay. More oompf on the back sorted that out. Boat balanced fine until I got my new main. Now the weather helm is very strong. So guess I nudge the mast up a little.
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I would strongly suggest that you get or do a rig inspection if you have not done so recently.
Do you have an adjustable head stay with or without furler?
What is the difference between old and new main sail?
 
I have a furler and the fore stay is not easily adjustable. Mainsail difference is only that the new one is NEW and the old one was end of life.
 
jfkal said:
I have a furler and the fore stay is not easily adjustable. Mainsail difference is only that the new one is NEW and the old one was end of life.
Click to expand...

Normally the position of maximum draft in a sail moves aft with age, so if you replaced the main with a new one of the same design, you would expect to see the opposite effect, with weatherhelm being reduced. I'm guessing therefore your new sail has come from a new loft / designer?

Anyway you have the right idea - move the rake forward until you're happy with the helm when on the wind with the correct sail trim / amount of backstay for the conditions.

One question - is your rig masthead or fractional?
 
jfkal said:
I have a furler and the fore stay is not easily adjustable. Mainsail difference is only that the new one is NEW and the old one was end of life.
Click to expand...
This doesn't make sense..

The reason I'm advice that you do or have someone do a rig check is that a halyard wrap on a furling head sail can cause an elongation (and weakening) of the head stay, thus needing to tighten the aft stay and as a result give more rake.

A new main sail with exactly the same dimensions should give less weather helm not more, assuming the new sail has better & flatter shape than the old one.

I however the new main has more roach than the old one you might need to reduce rake to get boat in balance with the new sail.

Some furlers have a turnbuckle as part of the furling unit or inside the furling unit.
 
Yeah you got it spotted. I came from a different loft and has slightly more sail area as it is higher cut (hope that is the right terminology. No turnbuckle only a crude plate with holes which would allow to shorten the forestay in 2 inch steps. Oh, and it is a masthead rig.

Many thanks
 
A 2" change on the forestay may be enough but the other option is to change the toggle. I've just had to move mine 4" at the top to vertical (possibly forward of) because of very slight change in sail size (34' boat). Helm is now just right. Andrew
 
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