MainSheet Blues

SG · Mar 13, 2019

The mid-boom sheeting doesn't seem like the "normal" sheeting for the Beneteau 281, it's end sheeted for a reason.

The companionway hatch means that the mid-boom sheeting is at the position that is close to where a boom vang would connect. Aside from having a lot of bending moment induced on the boom that wasn't intended, it's apparently left you with a situation where there is way to much tension on the main sheet to allow that boom to move.

Was this installation by some previous owner, or???

I think that the only workaround is to not sheet the boom in so tightly through a jib or tack. I suspect that you essentially either live with the boom "too loose" or you have to release and reset it.

Jackdaw · Mar 13, 2019

First you're right, thats not a great setup to start with.

Second, you can help the cause by having GREAT line as mainsheet (Maffiolli swiftcord) and very low friction blocks.

But no matter what, it will always want to by design want to pull down more than windward.

The Third solution is to rig a bridle between the two aft-most blocks, and rig the sheet from the boom to that. Dyneema and a good block. It will greatly limit the downward pull and allow the boom to get very close to centerline. I'd draw a picture but I'm focusing a great class of wine! ;^)

EDIT - Like this Jeanneau..

Stu Jackson · Mar 13, 2019

If you don't have a traveler and do have coachroof sheeting, you either need a traveler OR do what jack shows.

Buy Don Guillete's book, available right here on this site and read why.

SG said:
Aside from having a lot of bending moment induced on the boom that wasn't intended...

Not necessarily true. If the boat came that way, then all he's saying, and DID say and SHOW, is that he got one of the two versions that were made by the builder. Unless the drawings weren't for that particular boat.

jwing · Mar 14, 2019

I have the same problem on my boat, so I rigged a bridle similar to the one shown in Jackdaw's Post #3. It was a big improvement in performance, comfort, and safety. Keep in mind that the main sheet will lose some of its functionality as a leech shape controller and will serve more as a port/starboard trimming control. In other words, the mainsheet acts as a pseudo traveler. The vang then takes on more duty as the leech shape controller. I found that my vang was inadequate for that duty and I needed an upgrade.

I think that the rig shown in Post #5 will work about the same as the one in Post #3.

I offer this information to you as anecdotal data. My boat is much smaller than the Beneteau 281. The configuration of my boat allowed me to rig the bridle at the clew end of the boom and I bring the mainsheet forward to mid-boom so it is easy to reach from anywhere in the cockpit.

Jackdaw · Mar 14, 2019

therealbrianf said:
Thanks guys,

The image I included is taken directly from the Beneteau 281 manual.
Thanks for your advice, will look more closely at these options today.
I've also seen this setup suggested. Would very much appreciate your thoughts on it.
View attachment 162450
Regards,

Brian

That’s basically identical to the Jeanneau picture I posted. It’s just uses more blocks on the boom, probably to help support the load of mid boom sheeting. The blocks on the cabin top are probably unnecessary. Those individual lines could either be terminated there, or simply let the dyneema roll over the stainless steel.

Stu Jackson · Mar 14, 2019

therealbrianf said:
I've also seen this setup suggested.

Won't much change the geometry of the issue you first described. That's why they make "real" travelers.

www.garhauer.com -- best value in boat hardware.

Jackdaw · Mar 14, 2019

Stu Jackson said:
Won't much change the geometry of the issue you first described. That's why they make "real" travelers. www.garhauer.com -- best value in boat hardware.

On the other hand, I’ve never seen a cabin top traveler that was wide enough or easy enough to use to really warrant the name ‘traveler’. Simply too many compromises . On most boats I think the bridle and a good vang is a better choice. With well-thought-out geometry you can get the boom very close to the centerline and still have control over the leech. A great solution for all what serious racers.

Stu Jackson · Mar 14, 2019

Jackdaw said:
I’ve never seen a cabin top traveler that was wide enough or easy enough to use to really warrant the name ‘traveler’. Simply too many compromises .

Then you've never seen my boat. Wide traveler, extremely useful. It's twice the length of a Beneteau traveler on the same size boat.

Jackdaw said:
With well-thought-out geometry you can get the boom very close to the centerline and still have control over the leech. A great solution...

True, a great compromise, too.

jwing · Mar 14, 2019

Stu Jackson said:
Won't much change the geometry of the issue you first described.

Apparently, you have not sailed a boat that has a bridled mainsheet system. It is a great improvement over no traveler/no bridle. A traveler is a slight improvement over the bridle. If there is room on the boat and plenty of money in the budget, get a traveler. A bridle is cheap, easy, and uses less space.

Jackdaw · Mar 14, 2019

Stu Jackson said:
Then you've never seen my boat. Wide traveler, extremely useful. It's twice the length of a Beneteau traveler on the same size boat.

Knowing you I'm sure its a swell setup!

To me a good traveler has three characteristics:

1) Wide range of motion around the centerline, a) to pull above the CL upwind, and to dump below in pressure
2) Strong purchase and blocks to make it a hand load as long as possible (40 feet?)

The tricky one is 3) Well placed to allow it to be played easily with the main. This is were I see cabintop travelers suffer. The traveler location situates the user in the pit area, and also assures that the mainsheet will be on a winch at the cabintop as well, making the situation double clumsy.

I know that boats that are like that are designed that way for good reasons, but man there is nothing like a maintrimmer sitting next to the driver on the rail, mainsheet in one hand and traveler line in the other. The trimmer can feel the puff and the drivers reaction, and can instantly react to minimize rudder movement. Two identical boat going to windward on a puffy day, one like this and the other cabintop trimmed, all else equal I know who's going to win.

Gunni · Mar 14, 2019

If my trimmer is sitting next to the driver with travel and mainsheet lines in hand I’m going to tell her to calm down and go get a beer!

Travel well down and vang tight when off the wind, travel up to power twist the sail in light winds, center up when we need to flatten the sail. Heck I can do that with a cigar in one hand. But then the only win we need is an early arrival at the anchorage to get a spot near the dinghy dock.

If you have an 11 ton boat and you want to keep the boxcar on the rails, a nice traveler makes it a one man job, driver included.

Jackdaw · Mar 14, 2019

Gunni said:
If my trimmer is sitting next to the driver with travel and mainsheet lines in hand I’m going to tell her to calm down and go get a beer!

Travel well down and vang tight when off the wind, travel up to power twist the sail in light winds, center up when we need to flatten the sail. Heck I can do that with a cigar in one hand. But then the only win we need is an early arrival at the anchorage to get a spot near the dinghy dock.

If you have an 11 ton boat and you want to keep the boxcar on the rails, a nice traveler makes it a one man job, driver included.

Point taken.

But I will always start at the point of max performance/capability. You can always back off if your want to, but you can never add what was never there.

Meriachee · Mar 14, 2019

You can always upgrade what is there. Since putting the Garhauer traveler upgrade on the 270, and seeing as how it went to a 5:1, and with the redesign moving all the forces into a single plane, the ability to actually use the traveler without a winch handy turned it into one of the most used, and useful tools on the boat.

Little changes can yield large, sometimes unexpected results.

Stu Jackson · Mar 14, 2019

Jackdaw said:
The traveler location situates the user in the pit area, and also assures that the mainsheet will be on a winch at the cabintop as well, making the situation double clumsy.

I understand your performance POV. I had that on my Catalina 22 & 25!!!

End boom sheeting, tillers, all right there.

But, as you know, I am a proponent of "Don't be slave behind the wheel." I run my boat from in front of the wheel. The "pits" it is not!

I do not use the winch for the traveler because as meriachee says my traveler has a 5:1 or 6:1 purchase. I moved the cam cleats for the traveler to the aft edge of the cabintop.

Your boat, your choice.

Oh, I won a few races that way, too...

And it's true: No traveler single point>>>no traveler bridle ideas 1 then 2>>>real traveler

Good luck.

NYSail · Mar 14, 2019

In the picture you posted looks like plenty of space for a traveler....

bob_pattison · Mar 29, 2019

Without a traveler your vang becomes your de facto leech tensioned when the main sheet is eased.
Easy. Check out our tuning guide for the new 41.1...which outlines mainsail trim without traveler.
bob pattison
https://www.neilprydesails.com/images/pdf/b41_1_tuning_guide.pdf

jwing · Mar 29, 2019

Did I miss something in the tuning guide? I follow, and agree with the use of the vang to control the leach tension when the mainsheet is eased. However, when using the mainsheet to bring the boom in toward center, the sheet will also pull the boom down toward the keel, thus putting more tension on the leach. That overrides the vang setting.

The purpose of a bridle is to minimize the downward pull of the mainsheet, thereby maintaining the vang's control of the leach.

bob_pattison · Mar 29, 2019

What I'm saying is that vang is the tensioner. If pulling the mainsail to centerline puts more tension on the leech than the vang has done already, you don't have enough vang tension on.
The bridle is static. It doesn't minimize anything except your ability to trim your sail correctly.
On a set up like this and for all intents and purposes, the only thing the main sheet does is adjust the angle of attack of the mainsail by adjusting the boom in or out depending on wind angle.
So sailing up wind you bring the mainsheet in as tight as you can, then you pull on the vang until it reaches the same load as on the mainsheet and a tad more...and now it is handling your leech loading. You are free to adjust the angle of the boom to the wind by letting the mainsheet in our out and NOT lose leech tension each time you do it.
Think of it as mainsheet=traveler and vang=mainsheet
bob