Does a lazyjacks system need to be fixed so high on the mast?

johnalison

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Why is it heavy? I would have thought that for a tri it would be light weight. That is, after all, part of its performance advantage off the wind. My fully battened fibrecon mainsail on 31 ft mono is 8oz cloth & that should be plenty for a 30ft lightweight boat. My last dacron sail was 7oz
It doesn’t sound well sorted out. The Hydranet main on my 34 footer is pretty heavy and fully battened, and I have no purchase to help. In spite of this, I can just about haul it fully up. This is only possible if I release the clutch to reduce friction and have someone ready to close the clutch when the sail is up. It is also easier if I wear gloves and brace myself with a foot on the mainsail track which is conveniently sited low mid-cockpit.
 

Chiara’s slave

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Why is it heavy? I would have thought that for a tri it would be light weight. That is, after all, part of its performance advantage off the wind. My fully battened fibrecon mainsail on 31 ft mono is 8oz cloth & that should be plenty for a 30ft lightweight boat. My last dacron sail was 7oz
We have about 4 times the righting moment that you do. Your boat heels to absorb the energy. Ours stresses up the rig and pushes forward. That is the main reason multis are fast. Why we outperform sports 30ft monos, for example. Everything is bigger and stronger in the rig because of that. We have, for instance, a 24:1 2 speed mainsheet. I’m not notably weak, I pull that in by straightening my legs in anything more than 10kn, the load is up around 75kg by then.
 

Daydream believer

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We have about 4 times the righting moment that you do. Your boat heels to absorb the energy. Ours stresses up the rig and pushes forward. That is the main reason multis are fast. Why we outperform sports 30ft monos, for example. Everything is bigger and stronger in the rig because of that. We have, for instance, a 24:1 2 speed mainsheet. I’m not notably weak, I pull that in by straightening my legs in anything more than 10kn, the load is up around 75kg by then.
So I now understand that. You sail with the main sheeted in on most points & probably sail off the leech. Hence the sheet tension. ( I have 4:1 plus another 4:1 for trimming, ) But the question was -why so heavy? What weight is the cloth?
 

Aja

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Not sure it needs to be that technical.
It's two panels of canvas hanging from three strings each, via some mediocre line.
You make it sound like Nora Batty's underwear.
When I fitted lazyjacks I too had a good look at what others had done. The first thing that struck me was that those boats that had only 3 attachment points on the boom/sail cover had much larger gaps than this that had 4 attachment points.

I went with 4 on the boom. I also placed the blocks on each spreader (single, therefore about 50%) 300mm out from the mast. This gives plenty of space between the lazyjacks for sail raising and lowering. 4 attachment points ensures no parts of the fully battened main 'escape'.
 

LittleSister

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When I fitted lazyjacks I too had a good look at what others had done. The first thing that struck me was that those boats that had only 3 attachment points on the boom/sail cover had much larger gaps than this that had 4 attachment points.

I went with 4 on the boom. I also placed the blocks on each spreader (single, therefore about 50%) 300mm out from the mast. This gives plenty of space between the lazyjacks for sail raising and lowering. 4 attachment points ensures no parts of the fully battened main 'escape'.

Surely the optimum number of lower attachment points, and the ideal distance out on the spreaders (if the upper part is 'sprung' out), are entirely dependent on the size of the boat, or more specifically the size and shape of the mainsail?
 

Chiara’s slave

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So I now understand that. You sail with the main sheeted in on most points & probably sail off the leech. Hence the sheet tension. ( I have 4:1 plus another 4:1 for trimming, ) But the question was -why so heavy? What weight is the cloth?
We didn’t buy the sail, so I don’t know the spec, except it is visibly thinker and stiffer than any similar, or even substantially larger mono. And the leech has to support at least twice the tension yours does, and therefore corresponding increases in luff and foot tension. The mainsheet fine goes on the winch in 15kn, if the main isn’t winched up hard enough you get sags in the luff between the cars. Shrounds are 7mm dyform, the base is wide so loads there are contained a bit. The whole structure is very loaded. Have you heard the noises the SailGP boats make? Obviously way more extreme than us, but probably not as big as the gap between us and you.
 

B27

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I've used 2:1 main halyards on dinghies.
Half the rope stretch.
Each cm the rope stretches only lowers the head by 0.5cm, so 1/4 as much lowering of the head when lots of downhaul is applied.
 

Chiara’s slave

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I've used 2:1 main halyards on dinghies.
Half the rope stretch.
Each cm the rope stretches only lowers the head by 0.5cm, so 1/4 as much lowering of the head when lots of downhaul is applied.
It used to be common on cats, but for a long time now all the mainstream performance cats use a halyard lock and a f@&* off downhaul arrangement. 8 or 10:1 is normal. We don’t have a rotating mast, so a lock would be complex and fraught, and then there’s reefing to deal with.
 
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