Why are mainsails not hank on?

[SVPP]

That is potentially a really good idea.

The wire running down the mast could be used to resist bending/buckling. Mast tracks suck and this could be a much better way to deploy and retrieve a trisail also.

[Mike Banks]

Some mainsails are hanked on--it all depends upon your mast arrangements. A wishbone rig may be hanked on--and so may be its wishbones. A bipod mast system may have the mainsail either hanked on or on a furler.
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[dkenny64]

interesting question.
I was talking with a rigger about my boat a couple of days ago. mine has behind the mast furler just a jib but vertical..he hates them..and he has a good point. I think his point applies here...where is the loading on the mast..hank on and furler..are loading the mast at the top and bottom only.. cars/tracks/slugs all load the mast along its length..not just top and bottom.


just something to think about


-dkenny64

[Greg K]

Originally Posted by jmh2002

Loose footed mainsails came about way before and nothing to do with stack packs.

It's performance related. It's easier to adjust the outhaul and the foot of the mainsail if it's loose footed, and a better sail shape can be achieved.

So much so that on race boats whose rules forbid this a very light piece of sail cloth was used at the foot to attach it to the boom, just to meet the rules, but otherwise the structural attachment was at the clew.

This is really about modern sail development. Originally the load needed to be spread along the edges of the sail, but technical developments in sail coth and sail construction enabled highly loaded heads, tacks, and clews to be possible.

These days there is no need to the foot to be attached to the boom.

Thank you for the clear reply. Those are my thoughts, too, regarding sail development. Still, I wonder if even with modern sail advances, having the foot of the main attached to the boom to spread the load contributes to keeping the sail shape especially when hard on the wind (perhaps even contributing to reducing stretch over the life of the sail?)

Has anyone here noticed any change in their boat's sailing characteristics after switching to a loose footed mainsail? More weather helm, for example?

Greg

[Jim Cate]

Has anyone here noticed any change in their boat's sailing characteristics after switching to a loose footed mainsail?

Yep, way back when I was racing my Catalina 22 on SF bay, I converted to a loose footed mainsail. No difference upwind, but significant gains on the reaching legs. Won a lot of races in that configuration... and then the national committee (or whatever you call that class governing group) said it wasn't fair and banned them. This was in the early 70s; I suspect that things have changed by now.

But in general, if the sail is designed to be loose footed there will be no loss of shape to windward. I wouldn't have anything esle (and haven't in all those years since).

Jim

[Greg K]

Originally Posted by Jim Cate

But in general, if the sail is designed to be loose footed there will be no loss of shape to windward. I wouldn't have anything esle (and haven't in all those years since).

Jim

Thanks for the reply Jim. Your observation is similar to JMH2002 above. Always having sailed keel boats with mains attached to the boom, I remain skeptical that sail technology has completely eliminated the need for proper engineering. Surely, even modern laminates eventually succumb to the stress of the load not being spread along the edges of the sail? Perhaps not noticeable in the first or second season but, eventually, I suspect that the lower sections of the sail will begin to bag out much sooner than had the foot been attached for the full length. Advanced materials technology does not make good engineering obsolete, does it?

[Jim Cate]

Originally Posted by Greg K

Thanks for the reply Jim. Your observation is similar to JMH2002 above. Always having sailed keel boats with mains attached to the boom, I remain skeptical that sail technology has completely eliminated the need for proper engineering. Surely, even modern laminates eventually succumb to the stress of the load not being spread along the edges of the sail? Perhaps not noticeable in the first or second season but, eventually, I suspect that the lower sections of the sail will begin to bag out much sooner than had the foot been attached for the full length. Advanced materials technology does not make good engineering obsolete, does it?

Well, you are surely entitled to your opinion on this, and likely will be happier with a traditional sail. However, my experience and the advice of several experienced sailmakers indicates that you are wrong in believing that the sail shape will deteriorate much sooner with a loose footed sail... and you will have much better control of the shape for the life of the sail when it is loose footed.

Jim

[Pete7]

Originally Posted by dkenny64

I think his point applies here...where is the loading on the mast..hank on and furler..are loading the mast at the top and bottom only.. cars/tracks/slugs all load the mast along its length..not just top and bottom. just something to think about -dkenny64

No I disagree. My mast is 45ft, so the aluminium shaft inside the mast for the roller reefing is about 44ft long and say 2" in diameter. The majority of the shaft is going to touch the inside of the mast hollow when the main is deployed.

Pete

[MartinR]

Originally Posted by jmh2002

This is really about modern sail development. Originally the load needed to be spread along the edges of the sail, but technical developments in sail coth and sail construction enabled highly loaded heads, tacks, and clews to be possible.

These days there is no need to the foot to be attached to the boom.

Actually, loose footed mains predate modern sail cloth. Most gaffers had these long ago with very highly loaded tacks and clews.

My best guess is; the reason the foot was attached to the boom is that it was more efficient, as Dacron cloth had a lot of bias stretch and sails could be trimmed anyhow. Many modern cloths are very stiff, and without the loose foot can not be trimmed efficiently. But you loose the end-plate effect the boom gives partly.

[CF32907]

Originally Posted by roland stockham

On a traditional schooner rig the center sail (fishermans) was like an upside down jib. It was hanked to a wire that went to the top of the foremast then back to the mainmast and acted as both the luff wire and backstay. Sag in the wire was noticeable!

Your absolutely wrong about the Fisherman, it is not hanked . It's not a jib nor a main, nor a Staysail, it is a Fisherman, that is put aloft by halyards alone. It flies above the Main Staysail....
I owned and cruised the Caribbean on my 65' schooner "Altair"
Capt. Vince Rakstis, Ret.

[CF32907]

Originally Posted by CF32907

Your absolutely wrong about the Fisherman, it is not hanked . It's not a jib nor a main, nor a Staysail, it is a Fisherman, that is put aloft by halyards alone. It flies above the Main Staysail....
I owned and cruised the Caribbean on my 65' schooner "Altair"
Capt. Vince Rakstis, Ret.

The wire rope between the foremast and main mast is called the jumper stay, nothing is hanked to it...

[jmh2002]

The next boat that have in mind for myself solves this question in a different way, with no booms at all for the mainsails and yes mainsails, plural, since she is a schooner design too.

But not as famous as the Fife 'Altair' - kudos to you sir, I have seen the boat many times both in the Caribbean and the South of France, she is one of the very best

[barnakiel]

Where the main is hoisted along a stay, there are actually hanks.


It is just that few designs deploy main on a stay.


I think that on big sails hanks will create plenty of tension under load. Cars or sliders are easier to hoist and drop then.



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