When the rig is right should the downwind shrouds flop alot

tudorsailor

tudorsailor

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I have always wondered how one knows the rigging is set correctly. The cap shrouds are 14mm 1x19 so I cannot buy a strain gauge to measure tension myself.

I do recall when sailing on a beam reach in F6+ wind, the downwind shrouds were pretty floppy whilst of course the windward shrouds were tight! I do wonder if there should be that much play to allow the downwind shrouds to flop around but do I not know any better.

When riggers set the rig up and tune it, do they use a strain gauge? I wonder how tight is tight enough and how tight is too tight?

Sorry for being so niaive

TudorSailor
 
The correct tension is / can be set up by measuring the extension per meter of rigging as it is initially tightened. The Seldon guide to rigging and set up describes it.
 
Shroud tension

Hi

I don't know how big your boat is but I've been told that you can't overtighten shrouds on a 36ft boat. Anything you do is as nothing compared to how much strain the boat takes when she is on her side in a blow. The fore-and-aft tension is much worse for the hull because of the increased leverage and fewer bulkheads. Certainly you should not have floppy shrouds due to the strain when you change tack and the shrouds go tight.

Talk to the sailmaker who looks after your sails.
 
Slack Shrouds Are A Recipe For Premature Rig Failure

The leeward shrouds should not be slack so your rig is not set up correctly. Slack rigging can actually fatigue relatively quickly reducing its working life significantly.
 
In the Selden guide in addition to the "Folding Rule" method yYou will also find advice, for various rigs, on the angle of heel when sailing close hauled at which the lee shrouds should just go slack. In most cases they should not begin to slacken until the angle of heel reaches 20°.
 
Sail the yacht and check that the cap shrouds do not begin to slacken until about a 20° angle of heel

I just reached that part of the guide too. So the lee shrouds do go slack! This is reassuring

Anyhow, am due for a rig overhaul as yacht is now 10 years old and the mast has never been out

Thanks everyone

TudorSailor
 
tudorsailor said:
Sail the yacht and check that the cap shrouds do not begin to slacken until about a 20° angle of heel

I just reached that part of the guide too. So the lee shrouds do go slack! This is reassuring
Click to expand...

Yes, depending on the boat of course.

Here is a 32ft masthead sloop in no more than a good breeze:

http://www.youtube.com/watch?v=tIS-P3bJ6mY

Note the shrouds at about 30secs. A first class helm in charge for a YM test.
 
doug748 said:
Yes, depending on the boat of course.

Here is a 32ft masthead sloop in no more than a good breeze:

http://www.youtube.com/watch?v=tIS-P3bJ6mY

Note the shrouds at about 30secs. A first class helm in charge for a YM test.
Click to expand...

Dunno about the helm!!:D

But Gigi was Jeremy Rogers Contessa 32 and he knows a bit or two about the trim of them.

But every boat is different, what works for a CO 32, might not work for you

As long as the shrouds have tension in them when there are no sails up, I.e. Not floppy when she's on her berth you are a step in the right direction:)
 
Assuming the boat is GRP a little slack always happens on the lee side simply because GRP under load bends, metal boats don't. Pretty sloppy doesn't sound right but unfortunately isn't a very useful term as to how much it actually moves, please give us a clue.
 
Floppy is not good - with all due respect to the Contessa. Apart from the shock load on these loose shrouds when the rig flips over onto the other tack and they snap tight, there are toggles and pins that you have to be sure will realign correctly.
The leeward shrouds should lose their tension but not go floppy.
 
doug748 said:
Yes, depending on the boat of course.

Here is a 32ft masthead sloop in no more than a good breeze:

http://www.youtube.com/watch?v=tIS-P3bJ6mY

Note the shrouds at about 30secs. A first class helm in charge for a YM test.
Click to expand...

Very reassuring. Ours have less flop than the Co32 close hauled with 30 knots over the deck.

With deck stepped masts overtightening the rig can cause problems.

- W
 
Salty John said:
Floppy is not good - with all due respect to the Contessa. Apart from the shock load on these loose shrouds when the rig flips over onto the other tack and they snap tight, there are toggles and pins that you have to be sure will realign correctly.
The leeward shrouds should lose their tension but not go floppy.
Click to expand...

They'll never snap tight when tacking or gybing as the load is evened out as the boat goes through the wind. It's not a sudden change, no matter how fast you tack.

All rigging will go slack to leeward if it's blowing. The question is by how much. As long as the rigging is nice and tight when standing still then it's probably not going to come to much harm when sailing. Most rigs are far more robust than they need to be.

It's not so much a problem with smaller boats, but it's also worth remembering that over time, wire will stretch a little.
 
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