Chotu's Advanced Running Rigging Thread (lots of pics)

[s/v Jedi]

The three bails under the boom are for sheeting blocks.

I recommend against a vang because it doesn’t appear your boom has the reinforcement to deal with the forces.

[Chotu]

Originally Posted by rslifkin

I think the only thing stopping you from going with a longer traveler is the cost of buying one. Jedi's idea of using rigid columns for the outer angled supports would help with supporting a longer track as well.

But at the same time, I remember that discussion being predicated on the idea that "cats don't have vangs", but in reality, they don't because a really long traveler makes a vang mostly unnecessary. If you can put together a structurally adequate vang setup and there's enough clearance for it without hitting the front of the cabin, then a shorter traveler isn't nearly as much of an issue (and a closer spaced double mainsheet wouldn't be either).

In your case, you don't have swept spreaders so you can let the main out pretty far compared to a lot of cats. In my mind that makes a vang somewhat more desirable, as especially without a seriously curved track, you'll always be able to go well past the end of traveler range (no matter how long you make the traveler).


Basically, the goal is to have the ability to let the boom out far enough while still having the ability to pull the boom down when desired to control sail shape. So that can be done with either a really long traveler (allowing the traveler to position the boom and the sheet to control mainsail twist) or with a vang (sheet and/or traveler control boom position, vang controls twist when the sheet needs to be eased for positioning).

it’s important to note that I do have swept back shrouds. they are appropriately 9ft aft of the mast base. then another 12 ft farther aft would be the mainsheet attachment point. The sail and boom would hit those first

[Chotu]

Originally Posted by s/v Jedi

The three bails under the boom are for sheeting blocks.

I recommend against a vang because it doesn’t appear your boom has the reinforcement to deal with the forces.

Ah HA! On both counts. thank you.

I will definitely stay away from the vang. Would not want to fold the boom up

[Chotu]

I don’t know what I was starting to draw here. I was trying to envision the soft attach blocks on the strong points and how I could pull the boom down when it was let way out.

but the important part about this little drawing is I wanted to share the dimensions.

The roof is a total of 16 feet wide.

there are 8 feet between the columns, and 4 feet on either side of the columns. Wondering how this impacts even the traveler idea. The traveler can only be a maximum of 16 feet and it can’t even be that because it’s not supported out on those ends of the roof. it would surely bend/break at the ends.

in addition, it’s not really that much wider than the blocks. As you can see, I was starting to draw some Barbour Hauler blocks out on the hulls at deck level. but I’m not sure about that either because that’s a lot of crap hanging around. The unused lines would be kind of messy.

i’ll say it again. I definitely painted myself into a corner

[Cavalier MK2]

My mainsheet skips the traveller. Central block and tackle is the mainsheet. I then use a continuous line led from the boom out to the sides of the boat, amas in my case. The turn blocks are mounted where the end of the boom winds up when let out, the line then runs back to a winch by the mainsheet. This gives you both vang and preventer functions without having to re rig the vang. It can handle a very deep reach, To run the boom at 90 degrees you'd have to lead the preventer forward but I go fast enough the apparent wind moves things back to the deep position anyway. It takes the twist out and you can put the boom wherever you want it. To self tack release the preventer and put up with some twist till you can add some preventer again.

[Chotu]

Originally Posted by Cavalier MK2

My mainsheet skips the traveller. Central block and tackle is the mainsheet. I then use a continuous line led from the boom out to the sides of the boat, amas in my case. The turn blocks are mounted where the end of the boom winds up when let out, the line then runs back to a winch by the mainsheet. This gives you both vang and preventer functions without having to re rig the vang. It can handle a very deep reach, To run the boom at 90 degrees you'd have to lead the preventer forward but I go fast enough the apparent wind moves things back to the deep position anyway. It takes the twist out and you can put the boom wherever you want it. To self tack release the preventer and put up with some twist till you can add some preventer again.

wow. That’s exactly what I was drawing for the jib stuff after your other posts.

if I could find a way to just have a central Mainsheet like what you drew, this could work out. somehow I would have to have an extremely strong beam directly above those strong points where my roof and the columns meet. or potentially a piece of dyneema between the two of them and the main sheet block attached to that pulling upward.

you really only have to start pulling down on the boom once it is let pretty far out so this could work.

I could put this block next to my turning blocks for the spinnaker/code 0. as you said, located forward enough that it is below the bloom when it is eased way out.

my reservation is it’s a lot of extra line blocking ways to go forward. but I guess that’s a trade-off I would have to make in this case.

having a self tacking main and Jib? Now we’re talking lol

[Chotu]

I think the only real concern here is that the continuous line wouldn’t work on mine I don’t think. Because if one side is tight the other would be tight right?

as you can see in this drawing my roof would be touching the control lines when sheeted way in or when over toward the opposite side.

so, it could only act as a barbour hauler on mine. Pulling down when the boom was eased out enough to have that outboard line clear of the roof.

[rslifkin]

Originally Posted by Chotu

I think the only real concern here is that the continuous line wouldn’t work on mine I don’t think. Because if one side is tight the other would be tight right?

as you can see in this drawing my roof would be touching the control lines when sheeted way in or when over toward the opposite side.

so, it could only act as a barbour hauler on mine. Pulling down when the boom was eased out enough to have that outboard line clear of the roof.

Agreed, you'd need to do it as 2 separate lines because of the roof contact issue.



As far as structure for a central mainsheet mount, could you use another piece of that fiberglass square tube run across between the davits (and possibly attached to the davits near where the support columns attach)? If so, mount the mainsheet to something like that for load spreading and to add vertical stiffness between the columns.

[Chotu]

Originally Posted by rslifkin

Agreed, you'd need to do it as 2 separate lines because of the roof contact issue.



As far as structure for a central mainsheet mount, could you use another piece of that fiberglass square tube run across between the davits (and possibly attached to the davits near where the support columns attach)? If so, mount the mainsheet to something like that for load spreading and to add vertical stiffness between the columns.

kind of along the lines of what I was thinking also. Seems fairly reasonable. And if you happen to scroll back and look at the roof pic, you can see that I have another huge section of that square tube just sitting out there waiting to be used on something. it’s sitting along one of the davits

I was keeping it in order to put a traveler on it. but this would be a pretty good use of it I think.

[Cavalier MK2]

Well my line is long so the lee side is always slack but a line each side does the same thing and can use the same winch
There is some extra spaghetti but everything is a trade. The jib boom idea really works with just one line. I used it on a cutter for years. It could work on the mainsheet but then you'd still want a preventer so it wouldn't save anything really.

[rslifkin]

Originally Posted by Chotu

kind of along the lines of what I was thinking also. Seems fairly reasonable. And if you happen to scroll back and look at the roof pic, you can see that I have another huge section of that square tube just sitting out there waiting to be used on something. it’s sitting along one of the davits

I was keeping it in order to put a traveler on it. but this would be a pretty good use of it I think.

Regardless of traveler or central mainsheet that piece will be useful. If you wanted, you could always use 1 of the track pieces to do a short (6 foot) traveler between the davits, then have the additional lines to provide downforce when the boom is further out. That would allow you some extra control of mainsail twist when going upwind (as you gain the ability to pull the traveler upwind a bit to keep the boom centered but reduce sheet tension).

[s/v Jedi]

Originally Posted by Cavalier MK2

My mainsheet skips the traveller. Central block and tackle is the mainsheet. I then use a continuous line led from the boom out to the sides of the boat, amas in my case. The turn blocks are mounted where the end of the boom winds up when let out, the line then runs back to a winch by the mainsheet. This gives you both vang and preventer functions without having to re rig the vang. It can handle a very deep reach, To run the boom at 90 degrees you'd have to lead the preventer forward but I go fast enough the apparent wind moves things back to the deep position anyway. It takes the twist out and you can put the boom wherever you want it. To self tack release the preventer and put up with some twist till you can add some preventer again.

Can you explain in more detail how the continuous line works? It runs through three blocks?

[Cavalier MK2]

It doesn't need to be continuous. Basically the windward side is always slack and the lee side is tensioned for vang and preventer purposes. A continuous line just tames some spaghetti as you only have one line to worry about. It needs to be long enough to allow the boom to go out all the way on the lee side while keeping the windward side slack.

[s/v Jedi]

Originally Posted by Cavalier MK2

It doesn't need to be continuous. Basically the windward side is always slack and the lee side is tensioned for vang and preventer purposes. A continuous line just tames some spaghetti as you only have one line to worry about. It needs to be long enough to allow the boom to go out all the way on the lee side while keeping the windward side slack.

But where does it attach how? And how do you adjust it?

[Cavalier MK2]

Sorry that wasn't clear. Each end of a line attaches to the boom end. The lines then run out to the outer hull sides where a block is attached on the rail. The line then runs back to your mainsheet area to a winch and cleat. Since only the lee side is tensioned one winch is plenty all the main controls are in one place for easy handling. Again, tieing both ends to the boom make it continuous but it could be 2 separate lines I you want.