Shroud Tension

[bluefightingcat]

I've got a 5.25m day sailing dinghy (something like a GP14 or flyingScot). I was wondering what is the best way to ensure that my shrouds and forestay are tensioned enough? This is not a performance dinghy but none the less it would be nice to get as much performance out of it as possible. I'm relatively new to all this.

 

[fastyacht]

Spreaders or no? Wire luff or cloth (wire inside jib serves as forestay, or do you hank or slide your jib over the forestay)? Forestay tension is important aspect of upwind performance. The sail will have a certain optimal tension range built in.

Shroud tension depends on the rig--spreaders or not, bendy rig or not, the luff round of the main, wind speed etc.

 

[Rasputin22]

Check the Friday themed luff tension thread!

 

[Locus]

many boats have adjustable forestay and pins in the shrouds. Set the base tension when rigging using the pins and tighten the rig with the forestay. Or as above if the jib has integral luff wire us the jib halyard with some purchase to get tension. 

 

[bluefightingcat]

Spreaders or no? Wire luff or cloth (wire inside jib serves as forestay, or do you hank or slide your jib over the forestay)? Forestay tension is important aspect of upwind performance. The sail will have a certain optimal tension range built in.

Shroud tension depends on the rig--spreaders or not, bendy rig or not, the luff round of the main, wind speed etc.

Yeah it has spreaders. The jib is attached with hanks, so no wire luff. The boat is old, from the 80s, so there is not much information around about how much tension there should be. I was hoping for some sort of basic "rules of thumb" to try and experiment and see what works. 

 

[bluefightingcat]

I was reading up on this. Some say that forestay tension is not an issue since, the jib halyard will provide tension. As long the mast rake is ok then it's fine. Also I read that for the shrouds, it's enough that the leeward shroud doesn't go all untensioned when sailing upwind. 

 

[Terry Hollis]

On the type of dinghy that you describe with a floppy hull the maximum fore stay tension is determined by the main sheet the shrouds will determine the minimum tension.  Think about it,

 

[Rambler]

I was reading up on this. Some say that forestay tension is not an issue since, the jib halyard will provide tension. As long the mast rake is ok then it's fine. Also I read that for the shrouds, it's enough that the leeward shroud doesn't go all untensioned when sailing upwind. 

Without a luff wire, the rig tension will depend on the forestay.

With an old wooden hull, don't be silly about how much shroud tension you put in.

In similar (lower performance) Australian boats, the forestay would normally be tensioned by a lanyard on the base of the forestay, wrapped around with four or so loops between the forestay swage and the forestay fitting and tensioned by hand. For anything but top level racing, that's enough. 

 

[chuso007]

As a rule of thumb, you want them tight enough to keep the mast straight (laterally) most of the time except maybe when you are overpowered, then you might want the top of the mast to fall to leeward and open the top of the mainsail. Keep in mind that spreaders length and angle play a role in this too.

Go out sailing in 8-9 knots and see how slack the leeward shroud is, if too much, shorten it, tack and shorten the other side the same distance. In very heavy wind they should be slack, otherwise it means they are too tight for light conditions

Keep sailing and do adjustments until you feel the boat is always easy to control and doesn't feel slow.

As for forestay length, it'll determine you mast rake. It should be so that you have just a little weather helm. this means that if you let the tiller go, the boat will slowly turn upwind. (you shouldn't have to put more  than 2-3º angle on the rudder to keep the boat sailing straight). 

If it turns too fast, shorten the forestay if the opposite happens, let the mas fall back a little.

 

[bluefightingcat]

As a rule of thumb, you want them tight enough to keep the mast straight (laterally) most of the time except maybe when you are overpowered, then you might want the top of the mast to fall to leeward and open the top of the mainsail. Keep in mind that spreaders length and angle play a role in this too.

Go out sailing in 8-9 knots and see how slack the leeward shroud is, if too much, shorten it, tack and shorten the other side the same distance. In very heavy wind they should be slack, otherwise it means they are too tight for light conditions

Keep sailing and do adjustments until you feel the boat is always easy to control and doesn't feel slow.

As for forestay length, it'll determine you mast rake. It should be so that you have just a little weather helm. this means that if you let the tiller go, the boat will slowly turn upwind. (you shouldn't have to put more  than 2-3º angle on the rudder to keep the boat sailing straight). 

If it turns too fast, shorten the forestay if the opposite happens, let the mas fall back a little.

Thanks. This is what I'm looking for.

 

[chuso007]

That's what I thought