Rig Tension

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ReggieK

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Some time ago I dropped mast to replace the windex, we didn't have a tension gauge at the time and and re tensioned a bit tighter than before. Boat sails so much better it's incredible. However, I have been worrying we may have overtensioned. I put gauge on this morning and found Port & starboard shrouds to be 36 and forestay 38.
She is a fractional rig with 4mm stainless steel shrouds. The boat is sailing so much better I'm reluctant to release them but what do you guys think?
 
Tension should be around 230kg on the forestay and 160kg on the shrouds.
If you have a Loos Standard gauge (91M) that would be 38/40 on the shrouds and 42/44 on the forestay.
If you have the Pro series gauge (PT1M) that would be 30 on the shrouds and 35 on the forestay.
If it's not a Loos gauge I can't help.
 
But which Loos gauge? If you are using the silver anodised aluminium one that's the Standard gauge, the Pro PT1M is black.
You can go up to a maximum of 25% of the wire breaking strain, but that would be exceptional. Better to stay around 15% - 20%.
It's unlikely you are overstraining the rig - it's difficult to do with normal hand tools.
Your leeward shrouds should lose tension - but should not go slack and flop around
Here is some information:
http://www.saltyjohn.com/resources/Rig%20tensioning%20using%20the%20Loos.pdf
 
I have known a rig to be overtightened using hand tools. It depends on the construction of the boat. On the boat in question the chain plates were bolted to the forward bulkhead, and the holes through the bulkhead had elongated because of the stress. It wasn't terminal but did show what could happen if a gauge was mis-usd.
 
For advice on setting up standing rigging even without a tension gauge I recommend the Selden Masts "Hints and Advice" publication from HERE

Down load it and save it!
 
Hi Vics
Yes, I did download that before and the promptly forgot about it. There's good info there.
However, I'm inclined to just get in and drive and I never have the proper info to hand when needed.
We had a window to drop the mast and just dropped it, fitted windex, whacked mast back up and went sailing. The tension was a pure fluke that we hit it as it is and it made so much difference.Obviously originally the shrouds were too slack.
 
[ QUOTE ]
We had a window to drop the mast and just dropped it, fitted windex, whacked mast back up and went sailing.

[/ QUOTE ]

Could be that the improvement was damn-all to do wilth rig tension, and you were just using the windex!!
 
<<< There was an old rigging adage for the Mirror Offshore---"-if you can't open the loo door your rigging is too tight." >>>

With Sigma 33s it is said that the boat won't point unless the rig is so tight that the loo door won't open. Maybe says something about the relative hull rigidities of the two marques. I suppose it's 'bucket and chuck it' when racing.
 
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