Help Understanding my Rig...

[Niagara Les]

Hi Folks,
Just looking for help understanding something with my rig - maybe I need a crystal ball to look into the past, but thought I'd give it a go here anyhow.

We have acquired this old boat and have returned from a week aboard, maybe 10 hours actually sailing this boat so far, so excuse my ignorance if it seems I'm not so knowledgeable on my own boat!

The boat came equipped with an ancient CDI roller furling mainsail arrangement that makes setting the main really easy. The boat also came with a photo album from 1978 of the construction of the boat, including many pictures of the boat sailing with her original mainsail (no CDI roller furling fitted).

In the photos of the boat sailing without roller mainsail furling the clew of the sail extends to the end of the boom as I'd expect, the mainsail seems appropriately sized for the boat. In the photo I've attached, the main is fully set and the clew of the mainsail falls quite short of the end of the boom, the mainsail seems undersized.

The previous owner has no answers for us, and the boat seems to sail comfortably up to 15 knots of wind without furling (with genoa set).
The steering is hydraulic, so I'm afraid I have no real experience with determining if there is weather or lee helm (came from 24' boat with tiller).

My original thoughts were to remove the CDI roller furling and go with a traditional setup with lazy-jacks. After using this furler, I'm very surprised how well it works, and I'm considering using it.

Question(s) - any ideas as to why the sail would be undersized? I can't imagine why it would be undersized given how easy it is to furl. It appears that it was made for the furling unit, not adapted from a traditional setup (no batten pockets). Would this be normal procedure for roller mainsail furling for some reason?
Any insight, comments, suggestions with respect to this are welcome.

Les

[IdoraKeeper]

It could be either way. My old boat had prodigious weather helm without a reefed main. The center of effort was too far aft for winds over 10kts. Reefing would flatten the main. You need to assess how much weather helm you are actually getting. If its none then I would suspect the sail is not made for the boat.

[jongleur]

Almost looks like it is a headsail bent on instead
of a proper mainsail, though I don't know what
a mainsail would look like for that rig.

[maxingout]

Looks like a very long boom and a full size sail may create a great deal of weather helm.

If the former owner lived in an area with lots of wind, he may have gone for a smaller sail so that he did not need to do the furling operation on the main.

Two of the yachts that I have owned in windy locations almost always had a single reef in the main as we spend a lot of time sailing to windward, and I did not want the weather helm or excessive heeling.

[Paul Elliott]

Even with hydraulic steering you can still check for weather helm, if you can see the rudder or rudder post. Figure out what things look like when the rudder is centered (perhaps mark the post or hydraulic actuators), then see how far off-center you are when sailing.

[roverhi]

Trashing the hydraulic steering and going to a tiller would solve your numb wheel experience.

The main is loose footed with a lot of belly in the sail. If the outhaul was pulled tight, as it would be for windward work, the sail may not actually be short on the foot. You'll note that the traveller has a long track and the car is toward the forward end of its range to give the sail its fat shape.

It was common in the '70s for boats that were raced to shorten the foot of the sail for better rating. The IOR penalized mainsail area more than foretriangle so boats that were not originally designed to the rule would just chop a few feet off the foot of the main to take advantage of the rule. Also, if the boat had significant weather helm, shortening the foot of the sail would help this. The Tartan 34, designed to the CCA rule, shortened the boom twice in later production when the IOR rule was in effect. IIRC, shortened the boom 4' or so in the last iteration. Owners of the later boats or those earlier boats who had shortened the main foot, said it significantly reduced weather helm and made the boat more pleasant to sail.

[SkiprJohn]

Lots of older boats had long booms. It was a common design. Heavier air to windward work required reefing very early to keep the weather helm lighter.
The main you have might have been designed and fitted to rid you of that weather helm and if you don't seem to slide off to leeward while the rudder is amidships it is probably the right shape for your boat. I'd use it for a season or two and see if you suffer from slow speeds or from bad pointing ability. If it seems to work well I'd keep it even though I'm not a fan of furling mains. They've probably made some significant improvements since first introduced.

[Dave Lochner]

Could the short footed sail be a function of the room between the furler and the mast?

With a shorter foot the diameter of the rolled sail will be smaller. When furled, how much room is there between the sail and the mast?

A new sail will be stiffer and not roll as tightly, so there may be some room now, but not when the sail was new.

[Niagara Les]

Many thanks for the replies.

There seems to be a bit of a theme here with regard to possible mainsail sizing to correct for weather helm. Luckily for me there are marks on the top of the rudder post to indicate rudder direction. While sailing to windward, the rudder seems a few degrees off centre to windward, although I haven't attempted to quantify exactly how much.

I'm wondering if fitting my emergency tiller (a good opportunity to try it out anyhow) would be a meaningful way to check for weather helm?

With regard to spacing between mast and furled main, there certainly seems to be a lot of room for more sail furled up.

Les

[Pete7]

Looks about right. Here is ours by comparison. A sail maker did offer me a new mainsail with vertical battens to increase the roach but I am not convinced as I think all this would do is increase the weather helm and need reefing earlier. If you have a mast head rig then the Genoa is probably the real driving sail. Certainly I was worried about spending over £1000 only to find it didn't make a large improvement. Spending the money on a folding prop would be just as productive and less of a gamble.

Pete

[SkiprJohn]

Originally Posted by Niagara Les

Many thanks for the replies.

There seems to be a bit of a theme here with regard to possible mainsail sizing to correct for weather helm. Luckily for me there are marks on the top of the rudder post to indicate rudder direction. While sailing to windward, the rudder seems a few degrees off centre to windward, although I haven't attempted to quantify exactly how much.

I'm wondering if fitting my emergency tiller (a good opportunity to try it out anyhow) would be a meaningful way to check for weather helm?

With regard to spacing between mast and furled main, there certainly seems to be a lot of room for more sail furled up.

Les

Yes, on the emergency tiller opportunity. You'll be able to tell right away if you have too much main up or whether the helm is balanced or not.

[Ex-Calif]

sailboatdata.com lists the E dimension as 14.20'

NAUTILUS 36 sailboat specifications and details on sailboatdata.com