What's that "rear stay" on a gaff rig?

[GregX999]

If you look at this pic, you can see, what looks to me, to me some sort of stay going from the mast to the hull about halfway between the mast and the stern.



What is that called? How is it used? It seems like it would be in the way if you wanted to let the mainsail out on a run. Do they move out of the way? Are they a pain to deal with?

I only see them on some gaff rigged boats. What determines if they should be included in a design or not? Sometimes they seem to attach to the hull much further forward and don't seem like they'd be in the way.

(I'm not talking about lazy-jacks. I know what those are, but these are not them.)

Thanks!
Greg

[bloodhunter]

Greg
Looks to me like a running backstay. Should be one on each side of the hull. You put tension on the stay on the windward side of the boat to support the mast. The stay on the leeward side is loosened enough so it does not get in the way of the main.
We have running backstays on Enchantress to support the mast when we fly a staysail

[JohnRPollard]

Originally Posted by bloodhunter

Greg
Looks to me like a running backstay. Should be one on each side of the hull. You put tension on the stay on the windward side of the boat to support the mast. The stay on the leeward side is loosened enough so it does not get in the way of the main.
We have running backstays on Enchantress to support the mast when we fly a staysail

That's right. They are running backstays. In case Greg didn't follow the explanation fully -- you must ease the working runner and take up on the lazy runner each time a tack or jibe is executed, much like the jib/genoa sheets.

They are common on gaffers like the one pictured, as well as many fractional rigged boats where the lightweight backstay is used more for flattenning the mainsail than it is for keeping the mast up right. They are less commonly used nowadays, where most fractional rigs are sprung tightly with aft-swept spreaders and shrouds.

You also see them on many cutter- rigs, where the runners meet the mast at the same hight as the forestay, to prevent the mast from pumping under the load of the 'staysail.

[Selkirk]

That's a cool looking boat. At least it is to me.

What is it?

And what's that little sail above the mainsail called?

[JohnRPollard]

Originally Posted by Selkirk

That's a cool looking boat. At least it is to me.

What is it?

And what's that little sail above the mainsail called?

It looks a lot like a Falmouth Channel Cutter, by Lyle Hess. Could be an Atkin design, too.

EDIT: Probably not an FCC, which were usually jib-headed cutters.

That's a topsail, usually the "first reef" on a gaffer.

[GregX999]

Running backstay... got it! Thanks!

When tacking/jibing, do they need winches, or is just a good tug and a cleat of some sort? (Assuming a 25-35 boat.)

It seems you would need to *really* let out the "lazy" one if you wanted to let the main sail out. On that boat anyway.

(I'm not sure what the boat is, I just google-searched until I found a picture of a gaff- rig that had, what I now know, a running back-stay.)

Greg

[bloodhunter]

Greg,
We use the secondary winches on ours, but you don't want to put too much tension on it. On the boat in your diagram, it looks like it just gets pulled manually .
i've never flown the stay sail when I had the boom way out but also have the stays rigged so I can pull the lazy one forward so it doesn't chafe the sail.

[jackdale]

Originally Posted by GregX999

Running backstay... got it! Thanks!

When tacking/jibing, do they need winches, or is just a good tug and a cleat of some sort? (Assuming a 25-35 boat.)

It seems you would need to *really* let out the "lazy" one if you wanted to let the main sail out. On that boat anyway.

Greg

"Traditional" boats do not have have winches; halyards, etc. are sweated. The lazy backstay does have to eased out a good distance.

Modern race boats (and some cruising boats) also have running backstays which require very close attention.

Jack

[WanderingStar]

If it's a not Lyle Hess it's probably a Paul Gartside design.

[Jeff_H]

Gaff rigged boats used a number of techniques to 'set up' (tension) the running backstays. Very often there was a two or four part tackle that was used to grossly release the backstay. This had a lot of line and was eased out with each tack. The other end of that line went to a small tackle that would then be used to provide the mechanical advantage needed to fully tension the stays. Another technique used to tension the backstays was a highfield lever, which was a device that tensions the stay with mechanical advantage that come from simple leverage. Small boats often used a system that had a track that ran along the deck that the backstays attached to and a tackle was used to pull the stay aft and tension the stay.

It should be noted that gaff rigs generally do not operate at the high level of tension associated with Bermuda rigs so these systems generally work acceptably well. In small boats you quickly get used to dealing with the runners and they become second nature, the hardest part being the need for very careful jibes. In bigger boats the loads get very big and the timing more critical.

Jeff