Symmetric or Asymmetric Spinnaker for Simplicity?

[thomm225]

The good thing about asymmetrical spinnakers is that you don't need a bow pole or any pole so you can handle them as a single hander.

But the asymmetrical spinnakers are usually flatter and for fast boats which is why they were perfect for single handing beach cats

[Alistair242]

We can fly our assym up to about 60 AWA(off the bowsprit) and the sail itself is considerably larger than our screecher so more effective in very light air.
But yes, agree that a screecher and a symmetrical spinnaker cover all bases if you have a bowsprit. If no bowsprit the assym will give you about 60 to near DDW.
Its worth getting a bowsprit IMHO as the screecher/code 0 is very useful in a lot of different situations.

[Chotu]

Originally Posted by Alistair242

We can fly our assym up to about 60 AWA(off the bowsprit) and the sail itself is considerably larger than our screecher so more effective in very light air.
But yes, agree that a screecher and a symmetrical spinnaker cover all bases if you have a bowsprit. If no bowsprit the assym will give you about 60 to near DDW.
Its worth getting a bowsprit IMHO as the screecher/code 0 is very useful in a lot of different situations.

I will definitely be getting a bowsprit. Definitely. But not right now. There are a lot of other rigging projects going on right now. Probably next year for the bowsprit. An upgrade.


Is it possible that where I have this wrong is I am thinking that I can bring the symmetrical spinnaker farther away from 180 than is possible?

If I get kind of far away from 180, will the apparent wind just collapse the symmetrical spinnaker? Is that the problem?

Also, how well does the asymmetrical work at 180? Is it equivalent?

Can I tack down the asymmetrical to my bows at 180?

Where do I put the sheet? I don’t have hardware yet. I have some cleats. I have a midship cleat and an aft cleat. These will be my attachment points for now.

[Alistair242]

With the symmetrical there is less adjustment because it does not have a straighter/shorter luff. It will collapse much earlier than an assym. The bridle system with blocks on either bow can move back and forth like a pole and guy system on a monohull giving you a little more leeway for both but the assym will always have a much wider wind angle range.
Assym can work at 180 with the tack on one bow with no main. You will still have a sheet on the other side running back to the cockpit. I have even seen people fly their code sails like this. Looks a little awkward but seems to work.
For the bridle system you need blocks as far forward as possible on each bow. The tack lines can be run aft through these or straight to your bow cleats from the block(harder to adjust under load). If you have no cleats or blocks right up on the bows you could attach blocks to dyneema straps at the extremity of your crossbeam on each side as the tack bridle points.
Sheets should be run outside everything to blocks well aft and then to a winch. These blocks will most likely work attached to your aft cleats.
Its hard to say exactly without seeing your boat but I am sure a rigger with cat experience could give you a path forward. Of course you need to make sure that all attachment points will take the load.

[Chotu]

Originally Posted by Alistair242

With the symmetrical there is less adjustment because it does not have a straighter/shorter luff. It will collapse much earlier than an assym. The bridle system with blocks on either bow can move back and forth like a pole and guy system on a monohull giving you a little more leeway for both but the assym will always have a much wider wind angle range.
Assym can work at 180 with the tack on one bow with no main. You will still have a sheet on the other side running back to the cockpit. I have even seen people fly their code sails like this. Looks a little awkward but seems to work.
For the bridle system you need blocks as far forward as possible on each bow. The tack lines can be run aft through these or straight to your bow cleats from the block(harder to adjust under load). If you have no cleats or blocks right up on the bows you could attach blocks to dyneema straps at the extremity of your crossbeam on each side as the tack bridle points.
Sheets should be run outside everything to blocks well aft and then to a winch. These blocks will most likely work attached to your aft cleats.
Its hard to say exactly without seeing your boat but I am sure a rigger with cat experience could give you a path forward. Of course you need to make sure that all attachment points will take the load.

This is finally starting to sink in. Thank you for the detailed yet simple description of this set up. I think I understand now.

For this kind of quick set up so that I can try things out this winter to motivate for more building of the interior, as well as fixing all of the damage on the exterior, the simple block on the aft cleat sounds brilliant. I didn’t even think of that. I was thinking I had to do a through deck penetration with a turning block.

Yeah I think it’s that fact right there that helps me understand how the asymmetrical might actually be better.

It can also carry me for more wind angles. I would probably be a set it and forget it type of sailor with it. Same like the symmetrical. But I have more wind angles that I can set it for. So that’s quite a positive feature. And if I can run at 180 with it, then it can do everything and a little more than a symmetrical spinnaker could.

Maybe I would also be able to change the tack around a bit and bring it more Leeward at times? That way if the wind changed directions and became a little bit more on the beam, I could maybe still carry it with the asymmetrical whereas the symmetrical would have collapsed?

If I am not trying to gybe the asymmetrical going downwind, which I definitely am not because I don’t want to do all that work when I’m trying to get places, then it should be equally as easy to operate as the symmetrical spinnaker. Would anyone disagree with that?

[malbert73]

They aren’t as different as you’d think. I have a pole, and often fly my symmetric off a bow cleat (monohull) on a broad reach without the pole. It’s fine. I’ve flown to 90 AWA in light air but I don’t need reaching help- I really want to power between 150-180 AWA which is where a symmetrical chute shines.
With a cat no pole is needed- just toggle between bow cleats or midline as needed
Asymmetric is sure more versatile (ie you add tighter reaching angles at the expense of DDW performance which IMO is where you really need it.
Finally, there are lots of used symmetric chutes as racers turn them over quickly. Asymmetric are scarcer and more expensive
I got a very nice used symmetric spinnaker for about $500 from Bacon sails in Annapolis. Makes me less hesitant to use it more often as I’m not afraid to shred it as I would be spending 2-4x as much

[fxykty]

Originally Posted by Chotu

This is finally starting to sink in. Thank you for the detailed yet simple description of this set up. I think I understand now.

For this kind of quick set up so that I can try things out this winter to motivate for more building of the interior, as well as fixing all of the damage on the exterior, the simple block on the aft cleat sounds brilliant. I didn’t even think of that. I was thinking I had to do a through deck penetration with a turning block.

Yeah I think it’s that fact right there that helps me understand how the asymmetrical might actually be better.

It can also carry me for more wind angles. I would probably be a set it and forget it type of sailor with it. Same like the symmetrical. But I have more wind angles that I can set it for. So that’s quite a positive feature. And if I can run at 180 with it, then it can do everything and a little more than a symmetrical spinnaker could.

Maybe I would also be able to change the tack around a bit and bring it more Leeward at times? That way if the wind changed directions and became a little bit more on the beam, I could maybe still carry it with the asymmetrical whereas the symmetrical would have collapsed?

If I am not trying to gybe the asymmetrical going downwind, which I definitely am not because I don’t want to do all that work when I’m trying to get places, then it should be equally as easy to operate as the symmetrical spinnaker. Would anyone disagree with that?

Yes, easy to disagree. In a straight line either sail will work fine and simply. But gybing is vastly different and like tacking, not something you can avoid if the wind or course changes. The symmetric makes gybing very simple.

If you want to run effortlessly 180* AWA then a symmetric spinnaker will be more efficient. The symmetric spinnaker will take you up to 90* AWA, but at that point you’d be using a screecher/code 0 or genoa. The asymmetric will do best at 150-160* AWA (optimum downwind angle is based on wind strength, but generally never lower than 170* AWA) and will certainly do better reaching, but DDW is not the happiest angle for an asymmetric.

For a symmetric you will need 2 lines minimum (a guy from each clew to the respective bow - you will need a high load block on each bow, or at very least lashed to a properly backed-up bow cleat). Ideally you’ll have 4 lines - on each clew you’ll have a guy to the bow and a sheet to a turning block somewhere far aft (again, a dedicated turning block or lashed to a stern cleat - there’s lots of load there when reaching so make sure your cleats are up to the job).

For an asymmetric you’ll need minimum 2 lines (a tack line to the windward bow and a sheet to your stern quarter). Second tack line and second sheet are needed if you want to gybe. If you want to run tight reaching angles (tighter than 130* AWA) with an asymmetric then you do need a bow pole - the tack line to the windward bow will allow the tack to rise too high and the sail will not work well. With a symmetric you can allow the tack to rise when reaching, so the windward bow location is just fine.

You’ll need a dedicated turning block for your future screecher/code 0 sheet anyway, so you may as well put in a pad eye or chainplate on each stern quarter.

Look for a used sail of suitable size of either flavour and try it out. If you’re not even sure whether you’re keeping your cat it doesn’t seem worth spending much time on this. BTW, the charter-oriented cats generally come with no downwind sails and you can often see threads here on CF as someone asks how to add a gennaker or spinnaker to their cat. That will give you some additional ideas of what’s needed.

[Chotu]

Originally Posted by fxykty

Yes, easy to disagree. In a straight line either sail will work fine and simply. But gybing is vastly different and like tacking, not something you can avoid if the wind or course changes. The symmetric makes gybing very simple.

If you want to run effortlessly 180* AWA then a symmetric spinnaker will be more efficient. The symmetric spinnaker will take you up to 90* AWA, but at that point you’d be using a screecher/code 0 or genoa. The asymmetric will do best at 150-160* AWA (optimum downwind angle is based on wind strength, but generally never lower than 170* AWA) and will certainly do better reaching, but DDW is not the happiest angle for an asymmetric.

For a symmetric you will need 2 lines minimum (a guy from each clew to the respective bow - you will need a high load block on each bow, or at very least lashed to a properly backed-up bow cleat). Ideally you’ll have 4 lines - on each clew you’ll have a guy to the bow and a sheet to a turning block somewhere far aft (again, a dedicated turning block or lashed to a stern cleat - there’s lots of load there when reaching so make sure your cleats are up to the job).

For an asymmetric you’ll need minimum 2 lines (a tack line to the windward bow and a sheet to your stern quarter). Second tack line and second sheet are needed if you want to gybe. If you want to run tight reaching angles (tighter than 130* AWA) with an asymmetric then you do need a bow pole - the tack line to the windward bow will allow the tack to rise too high and the sail will not work well. With a symmetric you can allow the tack to rise when reaching, so the windward bow location is just fine.

You’ll need a dedicated turning block for your future screecher/code 0 sheet anyway, so you may as well put in a pad eye or chainplate on each stern quarter.

Look for a used sail of suitable size of either flavour and try it out. If you’re not even sure whether you’re keeping your cat it doesn’t seem worth spending much time on this. BTW, the charter-oriented cats generally come with no downwind sails and you can often see threads here on CF as someone asks how to add a gennaker or spinnaker to their cat. That will give you some additional ideas of what’s needed.

OK. That sounds pretty doable. And you definitely understand the mission here so thank you for taking that into account and not trying to go for perfection on the first round here.

This sounds viable.

I know my cleats are good. Wow are they good. Two of them held this boat, with all the windage, through a direct hit of a category four hurricane where the eye went right over the boat at anchor. No damage.

I think they’ll be able to handle the spinnaker load. I guess we will see.

Sounds like a solid plan though.

Again, thank you for taking the time to really explain this simply and in detail at the same time. This was another really good post that helped me understand.

I honestly didn’t really know how to fly the Spinnaker when I first got one. I just hoisted it up there and connected it where it seems like it should connect and it worked. Ha ha.

I just want to make sure to get the socks so I can douse the thing when I need to. I remember that was the most nerve wracking part. Hoping that it would come down OK.

There is one question I have about your post. It’s about running tighter than 130 on the symmetrical spinnaker.

Instead of a pole, why couldn’t you move the “tack” side to the leeward bow and run the “sheet” back to the very stern of the boat?

That was what I was thinking of doing originally if I wanted to be a little more tight to the wind with the symmetrical spinnaker.

It seems like that would be easier than using a pole. No?

It would fix the sail in the direction that it needs to be for smaller AWA. But maybe there is a problem I’m not seeing?

[fxykty]

Originally Posted by Chotu

…
There is one question I have about your post. It’s about running tighter than 130 on the symmetrical spinnaker.

Instead of a pole, why couldn’t you move the “tack” side to the leeward bow and run the “sheet” back to the very stern of the boat?

That was what I was thinking of doing originally if I wanted to be a little more tight to the wind with the symmetrical spinnaker.

It seems like that would be easier than using a pole. No?

It would fix the sail in the direction that it needs to be for smaller AWA. But maybe there is a problem I’m not seeing?

If you move the tack line to the leeward bow (symmetric or asymmetric spinnaker) then you will rotate the sail too far to the side and all it will do is push you downwind. A monohull can run the tack line from their bow as their stern cleat is offset to leeward 2m or more, while your cat would only offset the stern cleat less than a metre.

No pole is needed on a cat for a symmetric spinnaker - you run the guys to either bow and that is enough spread. When running a tighter reach with a symmetric simply ease the guy from the windward bow until the tack is adjacent to the forestay. If it the tack rises too much then tighten the leeward guy to form a bridle that keeps the tack from rising too high. But don’t ever ease the guy so that the tack goes to leeward of your forestay.

[Chotu]

Ahhhhhh!!! I see!!!

That’s the final piece of understanding this symmetrical spinnaker stuff.

I get it now.

Again, thanks for taking the time to teach.

[fxykty]

Here are some pics from right now in a light NE (8-10 knots) and an AWA 95*. Spinnaker original to the boat flew from the hounds but we’ve moved the spinnaker halyard to the top of the mast so the sail could be a bit taller.

You can just see the sock bunched up at the top; the two vertical black lines are the sock up/down control lines.

[Chotu]

Originally Posted by fxykty

Here are some pics from right now in a light NE (8-10 knots) and an AWA 95*. Spinnaker original to the boat flew from the hounds but we’ve moved the spinnaker halyard to the top of the mast so the sail could be a bit taller.

You can just see the sock bunched up at the top; the two vertical black lines are the sock up/down control lines.

Attachment 269933
Attachment 269935

A picture is worth 1000 words on the set up of the rigging. Very nice. Thank you. I can definitely see the flexibility in “gybing” the symmetrical. Is it my imagination or does it look kind of small? Maybe it’s just distant.

That’s pretty cool that you’re at 95° AWA

I just saw an old video of the spinnaker that I used to fly. It was an asymmetric. So long ago I forgot. I’m going to put up a picture of that. I just have to open up an old computer to get it.

Question about that masthead attachment. I’m all for making more sell area like that. Is that not an issue? I remember in a rigging thread I had going people were concerned that my Mast is going to fall down. (What else is new ?) because I have a standard fractional rig that has a forestay, two cap shrouds and two lower shrouds. So they figured it was going to collapse forward without some additional rope stays that go aft like running backstays. I see you don’t have those and your spinnaker is attached at the masthead. It’s all good that way?

[rslifkin]

Originally Posted by Chotu

Question about that masthead attachment. I’m all for making more sell area like that. Is that not an issue? I remember in a rigging thread I had going people were concerned that my Mast is going to fall down. (What else is new ?) because I have a standard fractional rig that has a forestay, two cap shrouds and two lower shrouds. So they figured it was going to collapse forward without some additional rope stays that go aft like running backstays. I see you don’t have those and your spinnaker is attached at the masthead. It’s all good that way?

That might be a good question for your rigger. Depending on how much they know about the mast you've got, they should have a decent idea of how much pull it can handle at the masthead before additional support becomes necessary.

[Chotu]

Originally Posted by rslifkin

That might be a good question for your rigger. Depending on how much they know about the mast you've got, they should have a decent idea of how much pull it can handle at the masthead before additional support becomes necessary.

I guess this is more of a “what do people usually do” question.

So I am curious what’s happening in those above pictures.

One thing I know about my mast is it’s very over spec. It is thicker and stronger than the mast in the plans. (Higher moments) So if anything can handle it it can.

In fact the mast in the plan tapers at the top as well. But the spinnaker is not flown at the top either in the plan.

Looking at the shroud area here on my mast, this was taken today at the rigger’s.


Does anyone have some guesses as to all of these attachment points? Clearly I can see the tangs. What are those extra sheaves? Are those for halyards? Spinnaker halyards?

The base of the mast is to the right.

I’m 54ft to the spot they are pointing to from the base.

But I’m still not quite sure where the spinnaker halyard goes from this picture

From right to left, I’m looking at sheaves, I think a forestay attachment point? Then a pair of mounts for the double diamond spreader wires. Then God knows what for that off-center piece. Then the Tangs.

Is that correct? Does anybody know what that weird off-center piece is?

And with the spinnaker how you would go up to those sheaves that are pictured below the forestay attachment point?

Kind of seems like it would get caught in the forestay if that’s what that is.

EDIT: they seem to be pointing to yet another attachment point in the shadow. There sure are a lot of random things sticking out of this mast that I don’t understand. Do you think that is the hell you’re an attachment point and it’s just an outside halyard on a block? What is the other one for then? The one a little lower? More to the right?

[malbert73]

I think since you are likely to fly the spinnaker downwind, which reduces apparent wind, and usually in lighter conditions, if your mast can’t handle the chute it can’t handle usual sporty conditions with your white sails.
But, if you’re planning to sail hot angles in 25 knots with the chute up and flying a hull, that’s another thing