Chotu's Advanced Running Rigging Thread (lots of pics)

[s/v Jedi]

Just to get an idea, what is the layup of that roof? Is it cored, how much glass etc.

When you reinforce between the two vertical pillars, you still need to be sure about the fore-aft stability of that reinforced “arch” created for the sheet attachments. This is done by the rest of the roof.

I would begin with a simple sheet arrangement: connect the end of the sheet to the boom (better to the becket of a single block), then down to a single block on one pillar, up through a single block on the boom (the one with the becket) then down through a single block on the other pillar then up to a second single block on the boom then forward to the mast and on to your winch table.

This is a basic sheeting that should work and show you which way to go using simple blocks and it probably is good enough for permanent adoption. I have a similar arrangement on my mizzen boom except with only one block on the boom because I have a winch down at the second lower block.

The blocks may be too far apart for you, but when you create a roof reinforcement between the pillars, you could move them closer later.

[Chotu]

Originally Posted by s/v Jedi

Just to get an idea, what is the layup of that roof? Is it cored, how much glass etc.

When you reinforce between the two vertical pillars, you still need to be sure about the fore-aft stability of that reinforced “arch” created for the sheet attachments. This is done by the rest of the roof.

I would begin with a simple sheet arrangement: connect the end of the sheet to the boom (better to the becket of a single block), then down to a single block on one pillar, up through a single block on the boom (the one with the becket) then down through a single block on the other pillar then up to a second single block on the boom then forward to the mast and on to your winch table.

This is a basic sheeting that should work and show you which way to go using simple blocks and it probably is good enough for permanent adoption. I have a similar arrangement on my mizzen boom except with only one block on the boom because I have a winch down at the second lower block.

The blocks may be too far apart for you, but when you create a roof reinforcement between the pillars, you could move them closer later.

The roof is 1” core with 36oz of triax on both sides. same laminate as the hull. That’s 1220 grams per square meter on each side with a 25mm core to give you units you can more readily have an instinct for.

Fore/aft stability is enormous. that’s the one thing it doesn’t need. not only is the laminate defined above carried throughout the roof, but the davit beams continue all the way to the front windows of the deckhouse, through bolted every 24 inches or so. They are incompressible. My entire deckhouse roof would have to tear away from the hull to move the attachment points fore/aft.

Yes. the simple arrangement you are describing is exactly what i was planning to do. precisely. Although i am fairly tempted to do the same setup but with a sheet on each attachment point instead of a single sheet. that way, i could get some downhaul action in place of a traveler. probably worthwhile. What do you think?

and actually, if I do the second sheet, one for each attachment point, they definitely won’t be too far apart. In fact, the farther apart the better

[s/v Jedi]

Originally Posted by Chotu

The roof is 1” core with 36oz of triax on both sides. same laminate as the hull. That’s 1220 grams per square meter on each side with a 25mm core to give you units you can more readily have an instinct for.

Fore/aft stability is enormous. that’s the one thing it doesn’t need. not only is the laminate defined above carried throughout the roof, but the davit beams continue all the way to the front windows of the deckhouse, through bolted every 24 inches or so. They are incompressible. My entire deckhouse roof would have to tear away from the hull to move the attachment points fore/aft.

Yes. the simple arrangement you are describing is exactly what i was planning to do. precisely. Although i am fairly tempted to do the same setup but with a sheet on each attachment point instead of a single sheet. that way, i could get some downhaul action in place of a traveler. probably worthwhile. What do you think?

and actually, if I do the second sheet, one for each attachment point, they definitely won’t be too far apart. In fact, the farther apart the better

Great… can you attach blocks to those davit beams? Dit you say you had more of this beam material? Maybe put a beam across connecting the pillars to take some load off the roof. Bolt some G10 plates on top to connect them.

[Chotu]

Originally Posted by s/v Jedi

Great… can you attach blocks to those davit beams? Dit you say you had more of this beam material? Maybe put a beam across connecting the pillars to take some load off the roof. Bolt some G10 plates on top to connect them.

yes to all!

that is the plan, structurally. Also very easy to attach the blocks and use those springs to keep them upright.

no problem with any of that!

[Cavalier MK2]

That would work fine, not self tacking but easy enough. You would loosen the lee sheet when coming about then adjust things on the new tack. This is helpful as multis with lighter weight can be pushed into irons by the main on the new tack while getting the jib sheeted in. Easing the mainsheet cuts down on the weathercock effect.

[dwightsusan]

Our catamaran is a one off 48’ x 28’ high performance cruising cat. In any conditions other than high wind and high boat speed we typically find it necessary to back the working jib when tacking to avoid going into irons. I think, in our case, this negates any benefit of the simplification that might be offered by a self tacking jib.
As an aside, I too am lazy. However, offshore on our high performance cat demands muscle and agility. Offshore, we sail at a minimum with a skipper and 2 strong and agile crew. Even in light air, double reefed and running our “storm jib”, Masalama would be a handful for 2 of us.

[Chotu]

Originally Posted by Cavalier MK2

That would work fine, not self tacking but easy enough. You would loosen the lee sheet when coming about then adjust things on the new tack. This is helpful as multis with lighter weight can be pushed into irons by the main on the new tack while getting the jib sheeted in. Easing the mainsheet cuts down on the weathercock effect.

ok. great! This is the plan.

[Chotu]

Originally Posted by dwightsusan

Our catamaran is a one off 48’ x 28’ high performance cruising cat. In any conditions other than high wind and high boat speed we typically find it necessary to back the working jib when tacking to avoid going into irons. I think, in our case, this negates any benefit of the simplification that might be offered by a self tacking jib.
As an aside, I too am lazy. However, offshore on our high performance cat demands muscle and agility. Offshore, we sail at a minimum with a skipper and 2 strong and agile crew. Even in light air, double reefed and running our “storm jib”, Masalama would be a handful for 2 of us.

this post is interesting. Now, my sister ship is single-handed up and down from the Caribbean to the extreme north Atlantic every year. He doesn’t seem to have any trouble handling the boat. however, I don’t know the story with very small wind and backing the working jib. Not sure how he has made out in light air like that. it will be interesting to see how this part works. do you crack off the wind then do an arcing turn to tack in light wind? that’s a technique i made up on my last catamaran with dismal performance. it kept me from having to go back the jib. i’m also lazy. ha ha

i’m curious what your sail handling is set up like. How your running rigging is.
it shouldn’t require tons of muscle and agility, but yours does I guess. How do you have everything set up?

if i have properly googled your boat, it’s more high performance than mine owing to no wind resistance from the smaller deckhouse. looks like a fast boat indeed

PS: i love the name of your boat!

[nofacey]

Cruised extensively in a 50 ft cutter (only monohull), both headsails on furlers, plus big asymmetric in snuffer. LOVED being able to shift gears by going thru assorted furling combos without going on foredeck, would never ever go back to hanked on sails.
- but if you told me I could only have one foresail, it’d be a 120 on a furler.
That would give you the greatest flexibility with just one sail - admittedly has to be too heavy to be a great light wind sail, and furled to stormsail size it’s going to have shitty shape - but it’s the best compromise.

[HabibiDah]

Originally Posted by rslifkin

Compared to a track the downside is worse sail shape once you come off the wind a bit and let the sheet out. It's the same issue you'd run into with a mainsail with no traveler and no vang. Once you let the sheet out too much you've got no ability to pull down on the sail

Mmmm...not really. I just did 1200 miles with a 145 AWA and a self-tacking jib. Like most when deep off the wind, the wind doesn't change much and you keep the same configuration for a long time. (5 days for this trip.)

It only takes 5 minutes to run a line from the jib clew to the midship leeward cleat to pull the jib down and change the sail shape. Even if I had a non-self-tacking jib, I would have had to do the same thing to get the right shape and angle at those AWA.

[s/v Jedi]

Originally Posted by HabibiDah

Mmmm...not really. I just did 1200 miles with a 145 AWA and a self-tacking jib. Like most when deep off the wind, the wind doesn't change much and you keep the same configuration for a long time. (5 days for this trip.)

It only takes 5 minutes to run a line from the jib clew to the midship leeward cleat to pull the jib down and change the sail shape. Even if I had a non-self-tacking jib, I would have had to do the same thing to get the right shape and angle at those AWA.

Could you install twings with a self tacking jib to do that? I guess two low friction rings, one for each twing, on the single sheet?

[rslifkin]

Originally Posted by s/v Jedi

Could you install twings with a self tacking jib to do that? I guess two low friction rings, one for each twing, on the single sheet?

I don't see why you couldn't.

[MicHughV]

In lieu of a twing I often use a snatch block that has one cheek that can flip open to attach over the jib sheet. Though the main snatch block position can be adjusted for and aft on a track, it is a pain in the butt to do so.
It is a useful gadget.

[Cavalier MK2]

The twang about twings etc... is you have to go on deck to rig them, fine for those long tacks but takes getting your steps in for shorter boards. This is the thing about reefing too, on the mast or back in the cockpit. For myself I leave the halyards and reefing at the mast, less spaghetti underfoot, less rope to buy. Slab reefing is traditional and effective. I actually use an ancient Scottish roller furler from the 50s or 60s... or the 30s, it is ancient but works well with the round boom and other antique bits. This disqualifies me from any more reefing input. The basic question mast/cockpit remains, do you have to be on deck to furl the main anyway? One advantage of the mast is one less turning block and good halyard access if you have to jig things around. Same with the jib halyards, spinnaker socks etc... some things are best closer to the foredeck. Furlers are great but changing a sail on one happens up front.

[s/v Jedi]

Originally Posted by MicHughV

In lieu of a twing I often use a snatch block that has one cheek that can flip open to attach over the jib sheet. Though the main snatch block position can be adjusted for and aft on a track, it is a pain in the butt to do so.
It is a useful gadget.

Antal has snatch lfr’s … snap hook: https://defender.com/en_us/antal-snap-hook

Originally Posted by Cavalier MK2

The twang about twings etc... is you have to go on deck to rig them, fine for those long tacks but takes getting your steps in for shorter boards. This is the thing about reefing too, on the mast or back in the cockpit. For myself I leave the halyards and reefing at the mast, less spaghetti underfoot, less rope to buy. Slab reefing is traditional and effective. I actually use an ancient Scottish roller furler from the 50s or 60s... or the 30s, it is ancient but works well with the round boom and other antique bits. This disqualifies me from any more reefing input. The basic question mast/cockpit remains, do you have to be on deck to furl the main anyway? One advantage of the mast is one less turning block and good halyard access if you have to jig things around. Same with the jib halyards, spinnaker socks etc... some things are best closer to the foredeck. Furlers are great but changing a sail on one happens up front.

Of course you can rig twings beforehand and use them from the cockpit