staysail using luff low torsion rope versus wire stay

[allene]

Originally Posted by rockfordwoods

I am thinking of converting to a staysail using a low torsion luff rope and furler to be flown without the stay. That way when I am not using a staysail, I can just bag the whole thing and store it. I am unsure of the required luff tension (using the halyard) for the staysail and how that would affect the mast compression. It seems to me that since you would be using a halyard for the sail anyway, the net of the halyard/stay combination would be the same as that of the halyard using the low torsion luff rope. I have read some opinions that it is not possible to get,enough tension like this.

Does anyone have any experience with using this setup for a staysail?

I fly a 150 jib on its wire luff line free flying. If that is similar to what you are talking about then I have some experience with it. There are some limitations mainly in not being able to get good upwind sail shape. It is also a bit of a trick to take down except when running. Easy when running, just grab it high on the luff and pull it on deck. I can do that single handed as the halyard winch is on the mast. Up wind, and on a reach, it often gets wet, sometimes very wet when taking it down and it takes two people. If you are going to have the halyard winch back at the cockpit, you are going to need someone on the foredeck to take it down. Putting it up is not the issue, it is taking it down.

If you can put enough tension on the halyard, then maybe you can get good sail shape. I am limited by not wanting to break anything with an old boat. We fly the sail off a spinnaker block attached to an old bronze ring that is just not set up for downward loading, you may be able to get more tension on your halyard and therefore better upwind performance.

Hope this was useful.

Allen
L-36.com

[rockfordwoods]

I am thinking to use a luff furler like used on code 0 furlers ie Facnor.

[knuterikt]

I have a Facnor FX2500 that I use in three different applications.

The boat is a masthead rigged Beneteau First 38

1. Asymmetric set on a bowsprit (use the AFX conversion kit)
2. Solent jib tacked just aft of the head stay, 1:2 halyard just below the head stay
3. Code 0 set on a bowsprit (it can also be hoisted in the same position as the Solent jib

I need the 1:2 halyard to get enough tension on the stay sail, Another option is to rig a 1:2 tackle at the tack.

The Solent jib (came with the boat) have a high modulus luff rope, but it is also made with a luff tape so it can be hoisted on the head sail furler profile. I have always used it on the Facnor FX, never on the headstay.

The head sail is self tacking with one long standing batten (give more roach at the top of the sail while it can still be furled).

This is a flexible configuration that works well for us.

[knuterikt]

Originally Posted by allene

It is also a bit of a trick to take down except when running.

With a furler (non structural) as the OP suggests, this would not be a problem

[Brion Toss]

Hello,
A sail set on its own luff is not a novelty, any more than luff sag with such sails is. The benefit of stays is that they provide the function of keeping the luff relatively flat, without excessive tension, elasticity, or compression. This leaves the halyard to handle the job -- shared with clew and tack -- of projecting the sail in an efficient shape.
Where loads are lower, and sail fullness is desirable (i.e. off the wind) setting a sail on its own luff can be a good thing, but even then too much load and/or elasticity can be a problem. High modulus fibers don't change any of this; they just give us stronger, lighter tools to work with.
Even if you use a high-modulus rope luff, tied to a high-modulus rope halyard, you are still placing a greatly increased demand on the halyard and its gear (note that the furler swivels, winch, and clutch are not designed for this kind of load, and that the load is roughly doubled on the halyard block),because you are asking the sail and halyard to take on the function of the stay.
So at least for a storm stays'l, keep the stay. Then make it as easy and safe to set and strike as possible. A downhaul, properly rigged and led aft, can allow you to do both jobs from the cockpit; the sail is kept on deck, furled, with the downhaul slip-hitched along its length, until you need to hoist. This is simple, cheap, and utterly reliable.
Fair leads,
Brion Toss

[knuterikt]

Originally Posted by Brion Toss

(note that the furler swivels, winch, and clutch are not designed for this kind of load, and that the load is roughly doubled on the halyard block),because you are asking the sail and halyard to take on the function of the stay.

Seems Facnor have considered this in the sizing guide, numbers for the FX2500 on my 12m LOA boat.

Asymmetric: 90 m2 / 969 ft2
Code 0: 80 m2 / 861 ft2
Staysail: 30 m2 / 322 ft2

The 1:2 halyard for the staysail (solent jib = 26 m2) have the standing end attached to a stay tang while the running part goes over one of the mast head sheaves (via a lead block).

So the load on the winch/clutch/sheave is still acceptable.

The spinnaker halyard block attachment has been strengthened by fitting a new custom designed spinnaker crane (to carry the load from the code 0) and beefed up blocks.
The bowsprit have three positions (fully retracted, half way out and fully extended) and is fitted with an adjustable bob stay.

When we use the Code 0 the bowsprit is set in the half way out position.

The code 0 sets on 1:1 halyard but have an 1:2 adjustable tack line

My storm stays'l is set on a wire stay .

Note on loads:
When we bought this boat the solent jib was on the sail inventory.

The original setup by the PO had a halyard box (where I now have the stay tang) with a 1:1 halyard and a 1:2 tackle at the tack.
The sheave in the halyard box where lost - probably damaged by overloading, so yes there are forces in play here.

I think I can understand why - this is the procedure he described

Dont try this at home

ease the backstay tension
ease the tack
hoist the jib
pull in on the tack (1:2 or was 1:4)
tension the backstay to max

I have never used this extreme procedure (only used the halyard winch on the 1:2 halyard), and have still been able to get a good shape to drive the boat upwind.

[Brion Toss]

Hi again,
Sounds like bases are covered. I'm particularly glad to hear that the storm stays'l is on a stay. No surprise on that sheave; I've seen them crushed, even without the, um, enthusiastic tuning procedure of the previous owner. But I'd still recommend caution, as that 2:1 now gives you god-like power...
Fair leads,
Brion Toss