General Info: 2sd stay for a storm jib on a lagoon ?!

[a64pilot]

You hoist the sail, furled, then really crank down on the halyard, it’s roller furling so you furl and unfurl it just like a regular furling jib. It’s not difficult, even I can do it, and I don’t know what I’m doing.
You may be right about it not being good to go to windward, but it’s what type of system that video had, near as I could see.

[Almi]

Originally Posted by DavefromNZ

My L450 storm jib solution:
Attachment 171119

Hi Dave, thanks for the picture. Do you mind sharing a bit more info on size and where you attached it to. We have just purchased a "new to us" L440.
Thank you very much

[arsenelupiga]

not sure on L 440 and if L440 is made strong enough but on L 400 one can use bow sprit hull attachment points and have bridle thru net and then furling sail attached to mast at second spreader.

Would help for windward work with apparent wind to 45 kn. ANd smaller sail (or partially furled staysail) for more.

But not sure if it is worth it as second reef seem to do okay at 45 app in high winds and seas up. And one does not really want to go fast in such conditions to windward except in lake.

[fxykty]

Originally Posted by arsenelupiga

not sure on L 440 and if L440 is made strong enough but on L 400 one can use bow sprit hull attachment points and have bridle thru net and then furling sail attached to mast at second spreader.



Would help for windward work with apparent wind to 45 kn. ANd smaller sail (or partially furled staysail) for more.



But not sure if it is worth it as second reef seem to do okay at 45 app in high winds and seas up. And one does not really want to go fast in such conditions to windward except in lake.

Our boat (not a Lagoon) has a non-structural gangway between the main and front beams, so we can’t attach an inner stay anywhere between the two beams. So just as you’ve suggested we’ve decided to use the bow sprit whisker stay attachments to support the bottom end of the inner forestay; there’s basically a straight line (from the side) from the bow sprit attachments up to the top of the inner forestay. This will position the tack of the storm jib about 1.1m aft of the main forestay.

Given that we fly a 125sqm screecher from the bow sprit on a 2:1 halyard with working loads up to 2,000kg, I assume that a storm jib won’t put anywhere close to that load on the fittings?

This stay will only be used for a storm jib. We will use an external halyard to hoist the jib. Alternatively, could we use the inner stay as as the halyard and stay in one, so rather than terminating it at the mast fitting it continues around a block and down to the deck?

One thing to make sure of is that the head of the forestay is attached to the mast near an aft supporting shroud or running backstay - otherwise you risk over-bending and breaking your mast.

[fxykty]

Originally Posted by rom

Thank you Dave, nice setup ! but wrong title it's actually not a storm jib I am looking for but a sail that is about 50% of genoa. Maybe the english name is forestay sail, I am not sure.

That’s usually called a staysail.

[arsenelupiga]

Originally Posted by fxykty

Our boat (not a Lagoon) has a non-structural gangway between the main and front beams, so we can’t attach an inner stay anywhere between the two beams. So just as you’ve suggested we’ve decided to use the bow sprit whisker stay attachments to support the bottom end of the inner forestay; there’s basically a straight line (from the side) from the bow sprit attachments up to the top of the inner forestay. This will position the tack of the storm jib about 1.1m aft of the main forestay.

Given that we fly a 125sqm screecher from the bow sprit on a 2:1 halyard with working loads up to 2,000kg, I assume that a storm jib won’t put anywhere close to that load on the fittings?

This stay will only be used for a storm jib. We will use an external halyard to hoist the jib. Alternatively, could we use the inner stay as as the halyard and stay in one, so rather than terminating it at the mast fitting it continues around a block and down to the deck?

One thing to make sure of is that the head of the forestay is attached to the mast near an aft supporting shroud or running backstay - otherwise you risk over-bending and breaking your mast.

you got some good ideas i may pinch

re forces - high level estimate. assuming storm jib area is 10 % of screecher, say 12.5m2, and 2000 kg forces are achieved at 25 kn apparent, then storm jib would achieve forces of 200 kg at 25 kn app. For storm jib to achieve 2000kg, wind would have to be 80 kn apparent ~ factor sqrt(10). Seem strong enough...

One would have to verify that stay attachments are not build directional, ie that orientation is for max force in direction of bow sprit. In this case some discount of strength is required.

Inner stay as halyard sounds interesting as easy to install/remove.

One could use more than one attachment on mast to spread load. One would be where spreaders attached (very strong) and other say 2m lower, similar to spinnaker halyard...

why all these trouble - do you really need storm jib and not just well furled jib to keep moving?

[fxykty]

Originally Posted by arsenelupiga

you got some good ideas i may pinch



re forces - high level estimate. assuming storm jib area is 10 % of screecher, say 12.5m2, and 2000 kg forces are achieved at 25 kn apparent, then storm jib would achieve forces of 200 kg at 25 kn app. For storm jib to achieve 2000kg, wind would have to be 80 kn apparent ~ factor sqrt(10). Seem strong enough...



One would have to verify that stay attachments are not build directional, ie that orientation is for max force in direction of bow sprit. In this case some discount of strength is required.



Inner stay as halyard sounds interesting as easy to install/remove.



One could use more than one attachment on mast to spread load. One would be where spreaders attached (very strong) and other say 2m lower, similar to spinnaker halyard...



why all these trouble - do you really need storm jib and not just well furled jib to keep moving?

Why all this trouble? Because our deeply furled jib stops working well for going upwind at about 40 knots apparent. That’s not good enough for us, so I want a rig that will enable us to keep sailing (upwind) up to survival conditions when that’s needed. It would also move the centre of effort with the storm jib aft rather than forward with the deep furled solent.

Interestingly, our reefing guide tops out at 50 knots, so that needs some work as well (a particularly deep 4th reef I think, moused to the 3rd reef clew - the changeover of the mouse line to the outhaul for the fourth reef clew line is a problem to be solved still). Or maybe we increase all of the reefs, such that the 3rd reef ends up with 25% luff remaining rather than the 35% it is now?

Upper end of inner forestay is immediately below the forestay, so well supported by the shrouds and running backstay. Lower end is connected through to the whisker stay attachments, which are through-bolted pad eyes with large backing plates and appear multi directional.

Thanks for the sizing calculations; I think ours would be about that.

[DavefromNZ]

Originally Posted by Almi

Hi Dave, thanks for the picture. Do you mind sharing a bit more info on size and where you attached it to. We have just purchased a "new to us" L440.

Thank you very much

Hi Almi, here are some details:
10sqm
9oz Storm Orange Dacron
Includes: "Gale Sail" Luff Pocket with Hanks, Tell Tales, Leech Cord, Sail Bag etc. Cost was about USD1,000.

I.e it is hanked around the forestay with the jib furled (jib sheets tied down at the tack area). We used the gennaker halyard and found a better place to tie the storm jib tack at the base somewhere.

It is a Cat 1 requirement for offshore from NZ. Not sure if I would ever use, more likely to keep furling the jib down, then away, throw out the Jordan series drogue and hang on [emoji15].

Cheers
Dave

[rom]

Originally Posted by arsenelupiga

not sure on L 440 and if L440 is made strong enough but on L 400 one can use bow sprit hull attachment points and have bridle thru net and then furling sail attached to mast at second spreader.

Thank you arsenelupiga & fxykty, that's what I had in mind. The L440 comes with a sparcraft mast. A guy there told me (unofficially) that I could weld a inner forestay attachment 1 meter below the main forestay. I heard multiple times that you can basically do whatever you want on a mast up to 1m away from the stays & shrouds. Ok, but then I would need another halyard... not so simple.


The reason for me is the same as described by fxykty, at lower speeds ! From 20AWS I could easily use a smaller front sail. From 25AWS I need to roll the genoa, it is not efficient and puts lots of stress on the rigging. Broke the genoa furler in the middle of the Atlantic...

[arsenelupiga]

you made me think... at 45 kn apparent furled jib was maybe just good for reaching, any higher, bad vibrations went thru rigging and that is no good.

It is all good if going downwind, but what if you headed for bad quadrant or shore?

I have to get my boat ready for this as well as my ambitions increased. I would attach where main stay is and use block lower. At angle 30 degrees from the mast, it is then only 50 % force on block which is way better than 100%. And probably use some sort of dyneema setup without welding.

[rom]

Originally Posted by arsenelupiga

you made me think... at 45 kn apparent furled jib was maybe just good for reaching, any higher, bad vibrations went thru rigging and that is no good.

yes, I should have stated from the start that I am interested in going upwind in strong winds, well, say above 25AWS. From say 70AWA to 180AWA the furled genoa does the job well enough.


As you noticed the furled genoa vibrates a lot in strong upwind. That's probably what broke my furler after about 7 days in a row furled at ~42AWA ... and almost broke the forestay as well !

Originally Posted by arsenelupiga

I have to get my boat ready for this as well as my ambitions increased. I would attach where main stay is and use block lower. At angle 30 degrees from the mast, it is then only 50 % force on block which is way better than 100%. And probably use some sort of dyneema setup without welding.

I am not sure I get it, which halyard would you use ? oh, maybe on the L400 you have the mast with diamond shrouds so no other possible attachment point ?

[arsenelupiga]

Originally Posted by rom

I am not sure I get it, which halyard would you use ? oh, maybe on the L400 you have the mast with diamond shrouds so no other possible attachment point ?

no halyard as it would double the force on top fitting of that stay when tensioned.Instead install forestay II at spreader attachment level, pass thru the block at appropriate level on mast and tension it at the deck level where bridle from bows attaches.

issues :
- how to protect net from too much chafing on bridle as it moves up and down in heavy seas.
- how to store it away when winds get stronger further.
- diamond spreaders are in the way , how to install not to interfere with mast dynamics.

i think couple of bottles of red will need to be deployed to solve this one.... and keep in mind that maybe, just cant be done ...

[Almi]

It is a Cat 1 requirement for offshore from NZ. Not sure if I would ever use, more likely to keep furling the jib down, then away, throw out the Jordan series drogue and hang on [emoji15].

Cheers
Dave[/QUOTE]

Hi Dave, thank you so much for the info. We are seeing our sailmaker on monday so will discuss.

I am with you on the JSD....a question though - where have you planned to attached this to? I am struggling to find info/examples on where best to have it and i don't think our current cleats at the back will be strong enough - by looking at them from the engine room it looks like only a thru-bolt and no additional backing plate - unless I am blind.
thanks again
Almi

[DavefromNZ]

Yep, you need to add these upper and lower plates, PM me for the design specs. They add strength and otherwise the drogue would rub on the stantions. I have also included the a link to one from my YouTube series of 7 videos of the drogue deployed. Cheers, Dave
https://youtu.be/2JDnxUyVjvk