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Beam seas under power - board up or down?
Posted: Sun Mar 06, 2011 10:49 am
by Spirit of the Wind
I've had my

since 1996. One of the issues I have not been able to figure out is whether it is better to have the centerboard up or down when running a pass with beam seas. Intuitively, I would think that board down would limit the pendulum effect. However, just as intuitively, board down might cause the boat to trip over the board.
Any thoughts???
Bob Cameron
Re: Beam seas under power - board up or down?
Posted: Sun Mar 06, 2011 12:06 pm
by mastreb
depends on the speed you're motoring and the speed of the seas, but I would be board up any time I'm going over the hull speed of the boat (about 7 knots). I'm really only board down under power when I'm doing close in maneuvers near a dock at low speed, and even then if the current is unstable I go board up.
Re: Beam seas under power - board up or down?
Posted: Mon Mar 07, 2011 3:58 am
by NiceAft
I agree with mastreb, but not just the center board. Above 6 MPH , the rudders should be fully up also.
Ray
Re: Beam seas under power - board up or down?
Posted: Mon Mar 07, 2011 5:30 am
by jschrade
You will find that stability improves greatly with main up motorsailing in all conditions. Putting the dagger/centerboard down has more of an impact on steering a straight course and preventing the side slipping when going windward, it has little impact downwind.
I soon realized there was a reason all those sailboats motorsail up and down the ICW with their main up - makes a HUGE difference on our Mac26's.
Jim
Re: Beam seas under power - board up or down?
Posted: Mon Mar 07, 2011 5:50 pm
by beene
I found when caught in rough seas:
- all fins down
- max speed 7kts
- ballast in
- keel down, whatever you have
- if it gets real bad, try to take the waves at 45 deg
- pray...... a lot.......
G
Re: Beam seas under power - board up or down?
Posted: Mon Mar 07, 2011 6:30 pm
by NiceAft
I assumed that the beam seas that were being discussed, were regular seas. When things get rough, the Mac is not designed to be in it. Not that it has not been taken there, but it is not designed for prolonged rough seas.
If I remember correctly, Mad Mike replaced his rudder barckets with much stronger ones. The problem he had was with following seas, but the point remains the same. You are chancing your luck when venturing into rough seas with standard Mac rigging, and hardware.
Ray
Re: Following Seas with MAC X, M and Others
by Don T ยป Tue Aug 10, 2010 4:53 pm
Hello,
We actually had a couple of members here break rudder brackets from side slipping with a following sea. Mad Mike for one and a European north sea sailor for another. I saw a Mac X up at Sucia in the San Juan Islands (2006) that had huge rudder gudgeons ( 1.5" pipe IIRC) after a trip in the Caribbean. The ones I remember were X boats with the aluminum brackets. I haven't heard of a stainless bracket breaking.
Don T
Captain
Re: Beam seas under power - board up or down?
Posted: Mon Mar 07, 2011 7:23 pm
by mastreb
jschrade wrote:You will find that stability improves greatly with main up motorsailing in all conditions. Putting the dagger/centerboard down has more of an impact on steering a straight course and preventing the side slipping when going windward, it has little impact downwind.
I soon realized there was a reason all those sailboats motorsail up and down the ICW with their main up - makes a HUGE difference on our Mac26's.
Jim
Hi Jim--are you daggerboard down when doing this? And are you talking about below hull speed or on a plane? I can't imagine going on a plane with the main up could be safe at all.
Re: Beam seas under power - board up or down?
Posted: Mon Mar 07, 2011 8:14 pm
by Divecoz
Unless your docking.. Motor down All Board are up..Lots issues with waves above and below to be motoring around in bad water with the boards down..
BTDT Not Good...
Re: Beam seas under power - board up or down?
Posted: Tue Mar 08, 2011 4:13 am
by beene
The problem with that Div, is when in rough seas, your motor will continually leave the water going over wave crests.
Happened to me more times then I care to admit.
Heavy winds and seas, your prop leave the water, the wind grabs your 26 foot billboard and will turn it on a dime in a second with no fins in the water to stop her.
The Mac has zero steering under motor only when the prop leaves the water.
I would not have made it home safe without all fins down, main up the size of a beach towel, motor down, max 7kts.
I could hear the prop leaving the water on every wave crest.... not a good place to be.
Do not plan on doing that again..... but then again, ship happens.
G
Re: Beam seas under power - board up or down?
Posted: Tue Mar 08, 2011 5:34 am
by Divecoz
My experience was just the opposite, or so I have been told.. It was the Dagger Board being down that caused the issue.
Under power, D.board down, weather getting really bad. I decide to turn her around and head her home. I did it too slowly.. Before I had accomplished my 180, another big wave had rolled under me and caught the dagger board. The curl of the wave, used the D.B. as a lever... with me riding the crest of the wave , as a fulcrum, it almost knock me down.
OR so at least, that is what was explain to me ,here and at the Marina when I got back in. A couple sailors said, it wouldn't?? Have been so dramatic if, I had been under sail?? I dont know...?? I am not about to test it and see

Re: Beam seas under power - board up or down?
Posted: Tue Mar 08, 2011 9:18 am
by bscott
Since I reef early and go to a "hove to" ASAP, my main is down, my CB is out 6-7" and rudders down. I have put out a minimum jib to add a small amount of lift to stabilize the ride. I use the jib because I can control it better with the furler.
I get nervous just writing this post
Bob