Nacra 5.2 pulling to port

Hi All - I've heard discussion of mast rake affecting the boat pulling into the wind. My new (to me) 1982 Nacra 5.2 is pulling to port. Mast rake is neutral. Pulls into the wind when on a port tack and downwind when on a starboard tack. I'm thinking my rudders must be misaligned. A friend suggested maybe the hulls are not evenly secured or maybe bridle wires are adjusted to different tightness. Any ideas from the group? Thanks,

Scott

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Scott
1982 Nacra 5.2 "Great White"
Ledbetter Beach, Santa Barbara, CA
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Check to make sure the boat is "square" on the beams. Measure from a fixed point in the middle front of the front beam to the tip of each hull, should be the same measurement.

Make sure you haven't installed your rudders reversed right and left. Check to make sure you don't have two left or two right hand rudder castings.

Check that your shrouds are the same length and attached at the same hole on each side.

Everything should be symmetrical, probably something isn't.

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Damon Linkous
1992 Hobie 18
Memphis, TN

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Ok Scott,


1.Make sure the boat is square. port bow to starboard stern = starboard bow to port stern.

2 Hulls parallel with each other. port bow center line to starboard bow center line = port stern center line to starboard stern center line.

3 Bridle wires equal length
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4 Side stays equal length and connected to the adjusters in the same holes.

5 Rudders both all the way down so they are parallel, leading edges of the rudders should line up vertically. If one rudder is not all the way down this can cause the symptoms you mentioned.

6 With the rudders straight and down measure from about 6 inches below the boat from the leading edge of one rudder to the leading edge of the other. Measure the trailing edge at the same height. They should be the same. Some people run a little toe in maybe 1/8 inch.

7 Mast rotation same in both directions.

8 Mast straight and diamond wires "if any" equal tension.

9 Both dagger boards same length and set at the same height.

In my experience it's usually the rudders not all the way down on my boat. But I have measured and checked all the other I items when I bought the boat. Also always check new rigging with old to make sure the length is correct.

I see you are on the "Left Coast" I would expect the boat to pull to port. icon_lol icon_lol icon_lol



Edited by skarr1 on Apr 22, 2011 - 11:06 PM.
@ Damon - thanks for the help. I'll check all those things today and bring my tape measure! My new avatar is pulling to the port as well. Any suggestions on how to fix that?
@ Skarr1 - thanks for all the suggestions. I'll run through the list before sailing today.

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Scott
1982 Nacra 5.2 "Great White"
Ledbetter Beach, Santa Barbara, CA
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Yeah, provided the boat has always been aligned prior to now, and the straps are rivetted to the beams (i.e. no center bar)that is almost always caused by one rudder not pulling down all the way. Rudder misalignment could also cause that but if your rudders have always been fine before and you are using a non-adjustable cross bar, that is unlikely unless you bent something along the way.

Number of causes for the rudder pull down problem. The simplest is that one of the rudder bolts is too tight causing the rudder to bind in the casting (need a nylock nut so you don't have to torque the bolt to the point of binding). Similarly there could be something in the casting itself causing it to bind, worn bushing, grit, flake from the casting, deformation of the rudder itself. All are pretty easy fixes, you can make a temporary bushing from a milk jug. Or you could just not be pulling one down all the way (I rigged a 2:1 purchase on my pull downs to prevent that).

First thing to check is the rudder pull down and alignment on dry land - those are the easiest to check. Then the rigging and lasly the boat alignment. If the boat itself is badly misaligned it should be pretty obvious quickly but it is hard to tell weather it is slightly misaligned or completely straight. Better to cross the other simpler problems off the list before you get into microadjusting the hull alignment.

Also, probably a stupid thing to say, but don't try and adjust the hull alignment with the mast up. :) Don't laugh I'm pretty sure some have tried it in the heat of the moment.

Dave



Edited by Wolfman on Apr 23, 2011 - 12:30 PM.

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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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Check that the rudders aren't on backwards.

I know it sounds ridiculous, but I've seen it three times in as many years now -- the rudders get removed from the boat for the winter or for transport, but they are left together with the crossbar as a whole assembly, and then when put back on the boat they were unfolded 'backwards' so that the bends in the tiller arms are pointing 'in' instead of out, which makes one rudder toe in drastically...at least it's drastic when steering, not so drastic when you just glance at it.

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Rob
OKC
Pile of Nacra parts..
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prelives My new avatar is pulling to the port as well. Any suggestions on how to fix that?


I thought you had done that on purpose. icon_smile You just needed to rotate it to the right before you uploaded it. I've fixed it for you.

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Damon Linkous
1992 Hobie 18
Memphis, TN

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Look at your rudder castings and you will see a pin below the rudder arm rivets. Your rudder pull down rope has to go OVER this pin or the rudder won't "slam home" in the rudder casting. One slow sailing day I decided to replace those ropes on my rudders as they were getting a little frayed. Well, after a few malt beverages I managed to feed the rope UNDER that pin on the port rudder and ended up with the same WTF head scratcher you describe
Ooo, I forgot about that one. I went a whole season and a half with that problem, all the time wondering what the heck that pin was for. It changes the angle to give you more positive downpull.

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Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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