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ruipina
04-03-2009, 12:36 am
I was wondering if anyone would Know the shroud tension values for the rigging on a Beneteau Oceanis 351?:confused:

sailingdog
04-03-2009, 02:16 am
The tension is often based on the diameter of the shrouds. What is the specific problem you're looking to address?? There's a good basic article on tuning the rigging here (http://www.fxsails.com/article_rigtune.php).

Glenn Henderson
04-03-2009, 10:22 am
With the lack of numbers, you can start at the point where the leeward shrouds have a little slack when the sailplan is fully powered.

ITMaster
04-03-2009, 06:36 pm
The tension, like SD said is pretty much a function of the diameter of the shroud and is generally not much more than 15 percent or so of the burst yield of the wire. A Loos Gage and careful adherence to the instructions that come with it would probably be a fairly easy approach for you. Make sure your mast is set up properly before you start working on the shrouds though.

ITMaster
04-03-2009, 06:45 pm
the point where the leeward shrouds have a little slack when the sailplan is fully powered.

Help understand something here please Glen. I thought that the leewards should always have tension on them; not a lot, but minimal none the less. This way, in case of an abrupt transfer of heading from an abrupt wind shift or other uncontrolled event, that by having tension already on the (leeward, changing to windward) shrouds that there would be minimal transfer of "shock" load to the rig from the slack being abruptly taken up.

Am I far off base or do different rigs, such as the B&R, get set up differently? (As a Catalina owner, I'm fairly ignorant to the way Hunters and others get set up so please pardon my ignorance)

Thanks, Tom

Glenn Henderson
04-04-2009, 06:02 am
Tom,

When the leeward shrouds are tight, you are just adding more compression to the mast. Large safety factor in rig design makes up for dynamic loads applied when tacking. masthead rigs and fractional rigs are tuned differently but I think that principle applies across the range. Some racing classes have very loose rigging.

Ken13559
04-04-2009, 06:13 am
Glenn,
I've B&R rig and I cannot measue the forestay tension due to the headsail furler. So using the Loos gauge to tighten the cap shroud and lowers how do I know my forestay is good enough ?

Glenn Henderson
04-04-2009, 06:27 am
If your cap shrouds are properly set, the headstay fall into line. Keep in mind the sails are designed for an amount of headstay sag. All headsail on all boats are. Since the B&R rig does not carry genoas, sag is minimized. The B&R rig are mainsail dominant rigs. As a rule one is generally trying tp power up a headsail. Also my boats are designed to sail low and fast. They are not to be pinched unless in flat water with some breeze.