Asymmetric spinnaker on oceanis 37

[macdoug]

I want to get an asymmetric spinnaker for my oceanis 37. It is “factory set up” to take one with a spinnaker halyard and various sheets and blocks that have never been used by the previous owner. What concerns me is that the tack attaches to the anchor bow roller. The bow roller itself is strong enough, but is only attached to the deck by three bolts with fender washers.
Ideally I want to use a furling spinnaker as I mainly sail with my wife and anything not easy to use is likely not to be used. Will the roller be strong enough to cope with the tension required to furl etc.? Or do I need to install a backing plate to beef it up?

Judging by how a Selden extending bowsprit attaches I am trying to massively over engineer my set up which wouldn’t surprise me.

 

[Davidasailor26]

We use the asymmetrical on our 37, tacked to a block on the anchor roller fitting like you describe. Ours is in a sock, so not as much luff tension as a furler would be. I agree that the attachment of the roller to the deck doesn’t look that great, and I haven’t flown it in very high winds, but our roller is still attached after the times we’ve used it.

 

[SoSound]

A couple of years ago, my wife and I decided to forego the asymmetrical that we never used in favor of a code zero on a top-down furler. Part of that installation involved reinforcing the anchor roller. We absolutely love the code zero, and have put it to use many more times than we ever did with the spinnaker. The code zero is a much more versatile sail for us as well.

This wasn't taken with the reinforcement in mind, but it's the only pic that I've found where it's visible... there's a very large stainless steel ring on the starboard side of the anchor roller where the furler attaches with a soft shackle.

Here are some other examples that I came across when searching for what I wanted (nothing like what I ended up getting...):

 

[SoSound]

I did actually find another photo with the code zero in place...

And, in use

 

[jssailem]

Nice. Is that you in Watmough Bay?

 

[Joe]

SoSound's pictured rig looks pretty strong with that bobstay set up. That's some pretty serious work, but I like it. If it were me, though, I know that in the long run I'd want the selden sprit and furling code zero. So... I'd do it in stages. Spend the money for the sprit installation this year and sail it with the asym in the sock. When you've saved up 4 or 5 k, install the code zero and furler. Maybe sell the spinnaker to offset the cost, because you know you'll never, ever use it again once you get the other up and running.

 

[macdoug]

Thanks for all the replies. Much to think about. I have looked at the Selden bowsprit. Looks good, but by my understanding are not rated for a code zero, only an asymmetric. the carbon pole can, but they don’t make any of the holding rings strong enough for a 37 ft boat.

so the question is do I want an asymmetric or a zero? Or ultimately both if funds permit?

Most of the year we have good winds apart from a month in autumn where it is light (winds just beginning to pick up now we are heading into winter). So most of the time it is just downwind that we are slow. So I think an asymmetric might be more useful, but I am happy to be convinced otherwise.

I suppose I could do what sosound has done and that would work for both.

SoSound can I ask exactly how you strengthened the roller? Is it just a bobtsay welded to the bottom of the roller and hoop welded near the end to attach the sail to? Or was there other bits?

 

[Gerard56]

The bow rollers of O31, O34 and O37 are the same, same dimensions and attached to the deck the same way.
Here below the part I had installed between the two bow rollers to resist to the up lift efforts at the point.
If somebody is interested to have the sketch of this part, I would post it here. It is perfect for a code zero or similar type sail.
Only condition : you have to have two bow rollers

 

[SoSound]

SoSound can I ask exactly how you strengthened the roller? Is it just a bobtsay welded to the bottom of the roller and hoop welded near the end to attach the sail to? Or was there other bits?

@macdoug you are correct, the bobstay and hoop are welded to the roller… the bobstay and the hoop are a single assembly, and that assembly is welded to the side of the roller (not the bottom). I’m sorry… this thread caught my eye just as we left town for a week, so I can’t get a good photo for you until next week.

 

[macdoug]

I would love a close up photo. It seems to me that strengthening the roller will be a more straightforward (and possibly cheaper) option than putting in a retracting bowsprit, and will more than cover my sailing needs.

 

[SoSound]

I should be able to get you a photo in the next day or two. we have a 12 hour drive to get home again tomorrow, then I’ll get a picture.

 

[SoSound]

OK, @macdoug, I finally made it down to the marina with my phone for a picture. If the goal us to just reinforce the anchor roller, that certainly seems to be what was accomplished for me. There is a large oval hoop that was welded onto the roller. They laid it up against the flange at the front of the roller and welded along the entire length where it makes contact. They also welded the entire straight edge on the back side of the hoop. A big paydeye was installed trough the bow, and a large stainless steel turnbuckle joins those two components.

I always thought it was a bit of an inelegant looking installation. But, on the other hand the individual components are simple, strong, and stainless... it certainly appears to be sturdy enough to do the job. I don't think many other fixtures on the boat are built of materials of this size. I have joked that I could probably now have the boat hauled out by the anchor roller if necessary.

 

[macdoug]

Thanks for the pictures. I am sure something like this will work well for me. I just need my metal fabricator to get back from holiday.

 

[macdoug]

So I have the Bobstay in hand, but went to measure for a sail and am somewhat lost as to the way the spinnaker halyard runs. It comes out at the top of the mast then runs down through an eye at the same level as the forestay attaches. This means that if I hoist a furling spinnaker, the furler at the top will always be rubbing against the jib/jib furler. Does everyone’s halyard do this, or do I need to go up the mast and take the spinnaker halyard out of the eye?

thanks.

 

[jssailem]

Don’t know why the halyard is routed that way.
Mine top block is mounted on a crane at the mast head. Allows the sail to be high and out in front of the forestay.

Perhaps your spinnaker is not that large and the halyard path has a reason. I would test hoist the spinnaker at the dock on a calm morning. That may clear up the issues.

 

[macdoug]

I haven’t yet got a spinnaker. I was just going to measure up.

 

[Davidasailor26]

So I have the Bobstay in hand, but went to measure for a sail and am somewhat lost as to the way the spinnaker halyard runs. It comes out at the top of the mast then runs down through an eye at the same level as the forestay attaches. This means that if I hoist a furling spinnaker, the furler at the top will always be rubbing against the jib/jib furler. Does everyone’s halyard do this, or do I need to go up the mast and take the spinnaker halyard out of the eye?

thanks.

Yes, that’s how mine is routed too. I have a sock instead of a furler, so I just live with it being close to the headstay. My spinnaker seems to be sized based on that lower hoist point. I assume it’s set up that way to concentrate the forces at the top of the shrouds, rather than putting the force at the top of the mast where the only support is the backstays. But I’m not sure if the mast could handle having the halyard re-routed to just come straight from the masthead. You might be best off talking to a professional rigger about what’s best there.

 

[SoSound]

I found the quote for our system. We do not use the spinnaker halyard for our furler, we added an additional halyard for the Code Zero. Our system, according to the quote, uses a Seldén CX-10 furler, and we added a 2 to 1 low stretch halyard. From what I can see, the new halyard and the existing spinnaker halyard use the same retainer above our genoa, if not the same... it is very close. There is clearance between the two systems, they do not touch. Here are a couple more photos of our halyard configuration.