Running backstays

[sailcomp]

We bought a Tayana 48 and would like to learn how to use the running back stays. Can anybody recommend a book or a website? Thanks. Sandy

[TrentePieds]

I don't know that you need a book to learn this. Just consider what backstays are FOR. Their purpose is to prevent the mast from being bent off to leeward by the pressure of wind in the sails.

Generally with very few exceptions, the sail(s) in question are boomed sails, and in some cases even gaff-sails. As the wind comes aft of the beam these spars must be permitted to swing further from the centreline of the boat, and at some point the spar(s) would come to rest against the leeward backstay of the relevant mast. That obviously precludes further trimming of the sail.

But it happens that the backstay in question is on the leeward side of the boat and therefore has no work to do to support the mast against the wind pressure. That stay is therefore referred to as the "lazy" stay, and it can be (temporarily) dispensed with.

Dispensing with it without actually removing it is done by "slacking" it, usually by means of a device called a "highfield lever", named after the man who invented it. There are other means as well, but in modern times, on yachts that require "running" backstays, the highfield lever is the preferred means because it's easy to use and quick.

As you come about - bringing the head of the boat through the eye of the wind - you tauten the backstay on the NEW weather side by "laying over the highfield" and once you are through the wind slacking the one on the new leeward side. Nothing to it when you are "going about"

However, when you are "wearing" (coming over on the other tack by turning the stern of the boat through the eye of the wind) it's best to get your timing right so that the sail in question has been brought sufficiently "in" (towards the centreline of the boat) by adroit use of its sheet, so you can tauten the new working backstay BEFORE the gybe happens.

The act of bringing the stern through the wind is NOT what is called a "gybe", though newbs will often make that mistake. The "gybe" it the act of the boom swinging over from one tack to the other. An uncontrolled gybe, called an "Irish" or a "Chinese" gybe depending on your preferences/dislikes, can dismast you. The act of turning the boats stern through the eye of the wind is, as I said, called "wearing" or more formally "wearing ship". "Gybing" is only a part of the evolution you go through when wearing ship.

Hope that helps.

TrentePieds

[wagsea6b]

Tayana 48 DS owner here. Take a look at where the staysail stay connects to the mast, somewhere about 2/3 up. When that staysail gets loaded up it can impart unbalanced force on the mast. The runners attach to the mast at almost the same point and help balance the rig. If you aren't using the staysail then the sloop rig is well balanced on its own and you don't necessarily need the runners.

We always use the runners when running with the staysail and on long passages as we will have multiple sail configurations and the runners provide additional protection.

[Annie in WA]

on many modern cutters and double headsail sloops the running back is rigged to support the mast where the staysail attaches to the mast. On non fractional rigs the backstay supports the mast where the main headsail attaches at the top of the mast. The running back does the same job but for the staysail. Running backs are usually not permanently run aft since on many boats it interferes with the mainsail. If you are on starboard tack with your main and staysail to the port side then the running back is attached on the starboard side aft to support the mast there and stop the mast from pumping.hope this helps

[Singularity]

Originally Posted by wagsea6b

... Take a look at where the staysail stay connects to the mast, somewhere about 2/3 up. When that staysail gets loaded up it can impart unbalanced force on the mast. The runners attach to the mast at almost the same point and help balance the rig. If you aren't using the staysail then the sloop rig is well balanced on its own and you don't necessarily need the runners.

Supporting the above, here's a ~20min video from 'the rigging doctor' that shows (starting at about the 9 minute mark) how/why the running backstays, using a little model to explain things. Video starts a little quirky but OP might find the gestalt in the entire video helpful:
https://youtu.be/hQf_dmMduV4

[JPA Cate]

Recommend a book? Brian Toss's book on rigging. If you use the CF Custom Google search feature, there are a number of running backstay threads that may help.

The purpose of the running backs on our boat is to keep the mast in column, and they are used to "balance" the staysail. Ours is a fractional rig. Often the runners attach at about the same height on the mast as the staysail (in our case a Solent sail). When you are out sailing, go forward to the mast and look up the sail track. It should be straight, even when you are heeled, no kinks or wows, and the leeward shroud only slightly soft. If it is not straight, you will need to tighten the appropriate stay to make it straight. Do this process on both tacks until you can see that it is straight. If you have astigmatism, get someone without it to tell you when it is in column. And form the habit of checking the rig from time to time, to be sure it all stays right.

If your runners are set up with tackles at the ends, rather than the Hyfield levers mentioned by Trente Pieds, there will be another chainplate for them to attach to, way aft on the boat, or a strongly back plated pad eye. If your boom swings clear of the runners, you can leave both of them set, which will prevent the mast from both coming out of column forward (which can cause it to break) and pumping, while you are going to weather. This saves you from having to tack them each time you tack, or wear ship, which is already a busy time. Obviously, if the boom does not clear the runners, you cannot leave the leeward runner on...and you should slack it any time the mainsail bears on it.

If you have tackles on the runners, you may be able to snug them up by hand, or they may need to be tightened on your secondary winches. What we did was to install sheet stoppers that the tails of the tackles come through before they get to the winch. Be sure they are strong enough to take the loads. After they are snug, you can take the line off the winch, and flake it down so that it will be free to run, when you cast off the runner as you tack or gybe. (In this case, the sheet stopper acts a bit like the Hyfield lever in TP's example.) If yours has a cam cleat on the bottom, you'll have to release that.



Ann

[barnakiel]

Tayana 48 will have a fat mast extrusion so the runners will be there to stabilize the mast when the inner jib is working hard.

b.

[Mike OReilly]

As other have said, the running backs are to equalize the mast load when using the staysail on a cutter. I only rig them when winds are up around 20kt or more, or if we're into lumpy, banging seas. I figure my stout mast and rig can manage below that.

And on our boat I rarely use the staysail on a run, so I don't have to worry about the main boom swing room. But when we're under hard press with wind abeam or forward, the runners get clipped on.

[StuM]

Originally Posted by TrentePieds

The act of bringing the stern through the wind is NOT what is called a "gybe", though newbs will often make that mistake. The "gybe" it the act of the boom swinging over from one tack to the other.

Or more generally, swinging any sail from one side to the other when the wind is astern.
e.g. You also "gybe" the headsail in order to sail downwind "wing-on-wing" or "goose winged"

[Nicholson58]

Wind does not need to be astern. If you are running a staysail the runners are most surely attached at the same height as the staysail stay. Simply imagine the top of the mast cut away to this point. It obviously needs a stay. Use it any time the staysail is in play especially if the winds are stout. If you have a massive mast, you can get away with not using them in light wind. If you want to see their effect, lie on the deck and sight up the aft of the mast as someone cranks the Windward RB in.

We are a ketch. RBs on the mizzen and main. Mains are three part blocks and big winches. Mast is 12” X 7” X 80 feet.

[wingssail]

Originally Posted by wagsea6b

Tayana 48 DS owner here. Take a look at where the staysail stay connects to the mast, somewhere about 2/3 up. When that staysail gets loaded up it can impart unbalanced force on the mast. The runners attach to the mast at almost the same point and help balance the rig. If you aren't using the staysail then the sloop rig is well balanced on its own and you don't necessarily need the runners.

We always use the runners when running with the staysail and on long passages as we will have multiple sail configurations and the runners provide additional protection.

It has little to do with "balance" (except that it balances the load). In the case of the Tayana 48 the purpose, as he correctly states, it to oppose the load of the staysail stay. Without a running back stay the staysail stay could tend to bend the mast, slacking the stay, and in worst case allowing the mast to break.

The basic purpose of the running back stay is to prevent the middle of the mast from moving forward under any kind of load.

Originally Posted by TrentePieds

I don't know that you need a book to learn this. Just consider what backstays are FOR. Their purpose is to prevent the mast from being bent off to leeward by the pressure of wind in the

As for TrentPied's description, he is correct as it applies to the type of boat he is referring to. However, in a general sense running backstays are simply there to oppose loads on the mast which would pull it forward, and yes, they are "running' because they are generally placed in a spot which would interfere with the mainsail, therefore there needs to be two of them to allow one to run out away from the meanwhile the other bears the load.

Boats with square top mains use running backstays in place of permanent back stays so the main can be tacked or let out for downwind work.

On boats with multiple spreader rigs (such as older race boats) where there are no fore and aft shrouds, only athwartships shrouds, running backstays are used to prevent excessive mast bend. My own ancient boat has two sets (runners and check stays), and we must set them on every tack. We also have a "baby stay" to prevent inverting of the mast (bending the middle aft).

Many members of the "blue water" set will say that bendy masts with running backstay are unsuitable for a cruising boat yet the two old farts cruising this one have done nicely with such a mast for 34 years. What it allows is quite a lot of control over the mast bend and that, in turn, controls the mainsail shape and contributes to foresail shape.

Running backstays and bendy masts are not a problem for those sailors who don't mind getting involved with the sailing of their boats.

[Joli]

Same here, checks and runners to support the spar with inline spreaders. We have an inner forestay at the third spreader opposed by the runner, the check is about at the second spreader. We have no baby stay so tend to carry a fair amount of prebend induced at the hounds by moving the butt aft. Our truck is eccentric so will also as add fair bit of mast bend when the backstay is on hard.

It's surely a good thing to have the runners on when offshore just to help support the mast. Understand we're only taking about the weather runner, the leeward runner will be slack and probably secured forward, especially if there are flying blocks.

[Jim Cate]

Our previous boat had an inner forestay and in-line spreaders. The runners were employed when using the staysail, especially upwind. The mast was beefy and we never felt it to be at risk without the runner, but the stay, and hence the luff of the staysail, were quite slack without the runner and upwind performance suffered noticeably.

On our current boat, which is a fractional rig with sweptback spreaders, is quite different. The mast will stand well without the runner in winds up to ~20+, and everything looks OK. But again, the forestay goes pretty slack and the sail shape is baggy... yechh! Banging on a runner cures that straight away.

Being forever shorthanded, not having to play with the runners is good, so I had our current main designed with the first reef points just low enough that the sail clears the runners, and I can leave them both set. Great mast control, tight forestay and little effort.
If we have the Solent jib unrolled, tacking is simple even single handed, and in anything over ~18 AWS the boat speed is pretty good. For old fart sailors (ones not so enthusiastic as our younger friends on Wings) this is a good setup.

So, with stout masts and an inner forestay, runners are not likely really needed to keep the mast upright, but upwind performance will be better with them set.

Jim

[GILow]

Nobody appears to have mentioned it, but the running backstays on a cutter rigged boat not only keep the mast straight but they also maintain tension on the staysail luff and thus improve its upwind performance.

[wingssail]

Originally Posted by GILow

Nobody appears to have mentioned it, but the running backstays on a cutter rigged boat not only keep the mast straight but they also maintain tension on the staysail luff and thus improve its upwind performance.

"is to oppose the load of the staysail stay. Without a running back stay the staysail stay could tend to bend the mast, slacking the stay..."

Oh yeah...which would reduce the performance of the staysail