Currently not having a jib sail, my P18-2 has a strong tendency going into the wind; holding the boat on course requires a continuous effort pulling the tiller.

Having never sailed one with a jib, I suspect this is because of the missing jib sail.

However, could it be that the angle of the mast is not optimal? (We had to make a new standing rig from scratch, again no data to compare here.)

Thanks,
Dan

until you get better info, try this

it is usual practice to have a boat that will slowly turn into wind if the rudder is let go. (for safeties sake if you fall off or need to let go of the tiller etc.)

to do this you have the center of pressure on the sails slightly behind the center of balance of the boat

to sail a straight course with the sails set like this you will then need to pull slightly on the rudder

if you remove the jib, the center of pressure on the sail moves further behind the center of balance. so you have to pull MORE on the rudders to make the boat go straight

this is normal

if you are never going to fit a jib and don't want to always be pulling this hard on the rudders you could bring the rake of the mast slightly forward. this will have the effect of moving the center of pressure clsoer to the center of balance and so reducing the pull needed to keep it going straight

but don't rake the mast past vertical or you will get other, bigger, problems



edited by: erice, Aug 31, 2009 - 06:31 AM

Without a jib there is so much pressure from the mast back that the boat only want to head into the wind. The jib will help balance out the boat. You can rake the mast a little forward and set the traveler out a little and try different setting with your center boards to see what combination helps the best. When I sailed a P-18/2 I kept the mast straight up, no rake at all, but I was sailing with both sails. Best solution is to try and find a jib.

You can also rake your rudders further under the boat to counter the effect of weather helm.

PS you really should be able to find the factory lengths of your stays. YOu can call performance, or a dealer (I would think)



edited by: andrewscott, Aug 31, 2009 - 11:30 AM

Cat Dan, are you sailing because you don't have a jib? If that is the case I have one for sale, or you can get the jib from a Prindle 18 classic as well.



edited by: JohnES, Aug 31, 2009 - 01:28 PM

--
John Schwartz
Ventura, CA
--

The jib tends to moderate a lot issues that affect boat balance. Andrew is right that raking the rudders forward will decrease the perceived weather helm by giving you more leverage on the rudders (center of effort closer to pivot). The weather helm will still exist and have a negative effect on boat speed, you just won't feel it as much.

Erice is also correct. Too much mast rake will increase weather helm, but it is imporant to set mast rake for the conditions. I learned this the slow and painful way, so make sure that the mast is raked enough to avoid burying the leward hull and cartwheeling the boat.

If you have the rake set properly and are still getting a ton of weather helm, flatten the main and move as much weight aft as possible. A fuller main will have more heeling power and will tend to push the bows toward the wind.

Since you have centerboards, you have the option of partially lifting the boards to move the board center of force aft. This will also decrease weather helm. If you were running daggerboards, you can partially raise them to allow the boat to slip sideways, but that is a last resort as it is a little counter productive (you would be better off depowering first).

I have seen an adjustable mast step setup that allows the base of the mast to be positioned a few inches forward or aft of normal. I know the P18-2 doesn't have this, but setting the mast step further forward would also decrease weather helm.

Whatever you do, don't set the boat up to have no weather helm. You want the boat to turn into the wind if you are not able to reach the controls (for whatever reason).

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Whatever you do, don't set the boat up to have no weather helm. You want the boat to turn into the wind if you are not able to reach the controls (for whatever reason).

OR worse... leehelm... that will cause you to powerup as you fall off...

I actually get different helm (lee and weather) depending on wind conditions... and since my days usually start light with increasing wind (seabreaze) its impossible to set it up for 1 condition.

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I actually get different helm (lee and weather) depending on wind conditions... and since my days usually start light with increasing wind (seabreaze) its impossible to set it up for 1 condition.

I used to have the same issue when I sailed the eastern great lakes (based out of Kingston, Ontario). A thermal would build in the afternoon and a light breeze could turn into an exciting ride. The thermals cause problems (broken equipment etc) most years for people at Cork (Canadian Olympic training Regatta-Kingston). Luckily the water is relatively warm (around 70F) by then.

Dallas seems to have more consistent wind velocities.