My 1986 5.8 has a mast rotation problem. Her mast slaps around when her sails are off her and the wind picks up. I replaced the Mast Ball and this didn't help. Should I replace the Shrouds since they have probably stretched? What about adding a Mast Rotation Control bracket? I had one on my 1983 5.2, but my 5.8 is Boom-less.
If I do add a Mast Rotation Control Arm, how should I rig it? Anybody out there have any experience with a Sloppy Mast? I know, this is kind of a personal question, but I just gotta know.

If it's flopping about when the sails are off then you don't have enough tension in the rig. Make sure your shrouds are tight, have a friend pull down on a trap wire while you are adjusting each side to get a nice tight rig
But so tight the mast doesn't rotate at all.

--
Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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Also check the tension on your diamond wires.

--
Dave Bonin
1981 Nacra 5.2 "Lucile"
1986 Nacra 5.7 "Belle"
Winnipeg, Manitoba, Canada
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Is your 5.8 the same as the 5.7 & 5.0 boomless setups?
They look like this;

The lines are not rigged correctly, it should be an endless line, giving 2:1
I have an extra if you are interested in setting your boat up this way.

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--

here's what my 5.8 setup looked like. teal colored line was used as a rotator topping lift. this arrangement won't help you induce rotation, just reduce rotation.
j






Edited by arch on Aug 05, 2016 - 02:52 AM.

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Aquacat 12 (sold)...'87 Nacra 5.8 (sold)...'03 Nacra Inter18 (sold)
Venture 15 (sold)....'89 Nacra 5.8 (sold)...'91 Nacra 5.8NA (sold)
'99 Nacra Inter20 (sold)
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I don't have firsthand experience with the 5.8. I thought all the boomless models faced the wishbone forward?

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--

Here's a picture with the arm pointing forward. This arrangement enables over-rotation of the mast (>90 degrees) when on a broad reach. Also shown is rigging for a 2:1 control line. The block at the trampoline is secured by a short pigtail with a stopper knot below.



--
Kip
NACRA 5.8na
Chesapeake, VA
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I can't open the link...
Did you right click the image, select "copy image location". Then click the "image" button,(just below where you are typing), then paste your link.

--
Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
--

Here's the image. (I posted originally using my tablet and did not find a "copy image address" option.)

One thing I forgot to mention is that the working end of the control line is secured in a clam cleat attached to the front beam. You can see a portion of the starboard cleat at the right edge of the photo.



--
Kip
NACRA 5.8na
Chesapeake, VA
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