Traveler advise please?

[guido]

I have a mid 60s ish DS1 that I raced a bit this year and plan to do a lot more with next year. The boat came rigged with mid-boom sheeting from a a simple brass traveler track about 6" behind the centerboard trunk and a fixed car. It does a good job on my shins without really offering any enhanced sail control.

I'd like to be able to cleat the main at the desired leach tension and then be able to play the traveler in the puffs allowing a dump without making the sail fuller.

Does the Harken windward sheeting car let you do this? Or does it just let you bring the boom to the centerline and simplify tacking (not a bad thing but not what I want), in which case a simpler cheaper car might do the job I want better...

Or should I chuck the whole mid boom approach and go to the bridle style traveler like Phill uses on Lollypop? Simpler (though more dependent on vang power to control tension) and much easier on the shins but does this approach give less flexibility in puffy conditions?

Or is there another approach I am overlooking?

Any insight on current state of the art would be deeply appreciated!

Thanks!

[persephone]

Hi, I'm a QYC member, and oddly enough grew up in Stow. I'm not sure if we met or not. I have a blue hull/white bottom DS1 #6872. I raced a few times this past year.
Anyway I'd talk to Brian Wilson or John Kerr from QYC. Both are knowledgeable and tech savvy about their boats.
I'm not overly serious about racing and I use a non-traveling mid-boom sheet system so I can't be much help. Good luck.

[guido]

Hi Geoff,

I don't know if we have met yet I am horrible with names! I have John O'Brian's old boat, cream over turquoise. This just finished season I mostly sailed my Laser so I didn't get to know quite as many DS sailers at QYC as I would have liked to. Hoping to fix that in 2010.

I've met John Ker but have not had a chance to get his insight on this. I did discuss this a bit with Brian Wilson, but he did not have a lot of direct experience with the Harken windward car, so I thought I would open it up to the larger community.

Thanks for your pointers though! See you on the lake next year.

Guy

[K.C. Walker]

Guido,

I have mid-boom sheeting, as well, but no traveler, so my shins are in one piece. I'm in the process of accumulating blocks to move to end boom sheeting for next year. I've corresponded with Phill and he is of the opinion that midboom sheeting, even with a traveler, does not have any advantage over at the simpler end boom sheeting. These are his observations from national championships. He says that he does not play the traveler and most of the time leaves it centered. Dave Karan just uses a bridal with no traveler at all. Both of these guys are using vang sheeting with somewhere around 18:1 or 20:1. I've corresponded with Mike Gillam who is very competitive with Dave and a Thistle sailor, as well. Mike and Dave have their vang set up Thistle style with a swivel cleat on the centerboard trunk. You can see how Phill has his rigged in his gallery.

This Thistle article I thought was pretty interesting and seems to me could easily apply to a Daysailer. http://www.sailnut.com/rigging/losethecleat.pdf

KC

[ctenidae]

I considered converting back to the wire traveller, but my brother-in-law talked me out of it. his argument is that when teh mainsail is fully out running downwind, you end up with a huge amount of line out that you have to reel back in. My rough estimate is it'd be 15 feet, compared to about 9.5 for a mid-boom rig.

Anybody find the extra length of line to handle an issue? I'll probably leave it rigged mid-boom either way, since I like the smaller number of lines, but just curious.

[K.C. Walker]

Anybody find the extra length of line to handle an issue? I'll probably leave it rigged mid-boom either way, since I like the smaller number of lines, but just curious.

My problem with center boom sheeting is that it's 3:1 and too low in the cockpit to give me the leech control that I'm after. The 3:1 in the center position is pretty hard to handle when the breeze picks up under full sail. It's also difficult to de-power the rig. I've had end boom sheeting and it has the disadvantage of having more line to deal with, as you mentioned. However, the amount of line that you pull corresponds to the mechanical advantage. If you don't want to pull much line that makes it more effort.

KC

[GreenLake]

The mechanical advantage of a doubled line at the end of the boom, with center mainsheet control is 2.5:1. So you have a little less advantage compared to a true 3:1 center boom tackle, but downwind you have a large amount of line (doubled) hanging from the end of the boom. That extra line likes to foul on the horn cleats or even the rub-rail on the transom, not to mention any motor mounts. In light winds, the boom needs to be pushed manually to make the line run through...

Not huge problems, as far as I am concerned. (With 7/16th diameter my mainsheet is pretty hefty for comfortable handling).

[K.C. Walker]

GreenLake,

Would it not be correct if you consider end boom sheeting with 2 lines at the end and one in the center as being 2.5:1 then 3:1 in the center would equal 1.5:1. If we are using the boom as a lever arm, and that it is at 1:1 at the end, then the middle would be half that at 0.5:1. So, to get the same mechanical advantage in the center you would need 5:1. My guess is that the line in the cockpit floor would be roughly equal, while close hauled, with the same real mechanical advantage.

In light air on a run, center boom sheeting has less line distance in the air which is nice. Also, I like jibing with center boom sheeting better than with end boom sheeting. The problem with center boom sheeting is getting an effective traveler at reasonable cost and without cluttering up the cockpit.

The Melges 17 uses 6:1 center boom sheeting on a simple bridal. Has anyone tried a bridal in the center boom position? Here are some pictures where you can see how it set up. http://www.melgeseurope.com/boat.php?p= ... u2m69f8rq6 and
http://www.onedesign.com/class/melges17 ... es/031.jpg

KC

[ctenidae]

I'm not seeing the advantage to a bridle on the center boom rig. Seems like it really just adds one more place for things to go bad.

[GreenLake]

Would it not be correct if you consider end boom sheeting with 2 lines at the end and one in the center as being 2.5:1 then 3:1 in the center would equal 1.5:1. If we are using the boom as a lever arm, and that it is at 1:1 at the end, then the middle would be half that at 0.5:1. So, to get the same mechanical advantage in the center you would need 5:1. My guess is that the line in the cockpit floor would be roughly equal, while close hauled, with the same real mechanical advantage.

Yes, you are correct. Croby rig as usually set up compares to 5:1 center boom tackle.

In light air on a run, center boom sheeting has less line distance in the air which is nice.

Correct, and the weight of all of the line is at 1/2 the lever-arm.

Also, I like jibing with center boom sheeting better than with end boom sheeting. The problem with center boom sheeting is getting an effective traveler at reasonable cost and without cluttering up the cockpit.

Given that the Crosby rig is competitive, this seems very much a matter or taste, like you say.

[guido]

Interesting ideas. No Consensus but that's sailing...

I had forgotten the William Crosby was the one who developed the split bridle rig. I looked at the Snipe rigging pictures on the Annapolis Performance Sailing site (a great resource). Lots of interesting stuff there. Combine with the new light Ronson Orbit 40 Auto-ratchet blocks and the split tail main might be the way to minimize weight and bulk on the boom and still get decent holding power. Lots to think about -- that's what winter is for.

Thanks for the input! More thoughts welcome too.

Guy

[K.C. Walker]

Guido,

I'm curious why you might be considering the snipe style split main sheet? This is the 2nd mention of using the split main sheet in as many weeks. I was unaware of it previously. Mike Gillam mentioned that he uses this set up for his main sheet. In web crawling a little bit last night, what I gather is that in the Snipe class they started with the "Crosby rig" and at some point started using the split main sheet set up. At the end of the boom with the "Crosby rig" you get 2:1 purchase and with the split main a 1:1. The split main does center the boom where as the Crosby does not. Neither has any traveler so you will need to go with vang sheeting if you want leach control in puffs.

If you have 3:1 on your center boom tackle, the split main sheet set up would not change your mechanical advantage. So if you're satisfied with your purchase on the main sheet, ratchet blocks should do the trick for holding power. I don't know why for sure but it seems that the most popular ratchet block set up is 40 mm on the boom and 55 mm or 60 mm on the centerboard.

KC

[GreenLake]

Mine was set up with a split mainsheet with a becket block at the end of the boom. On coming aft along the boom, the sheet went around the block, through the two blocks on transom, and back to the becket. What I disliked most about this setup was that because of the pull on the becket, the sheet would leave the block at an angle. I guess I could have fixed that by providing a different anchor point. However, I eventually converted to the Crosby after reading Phill's description of his rigging.

Honestly, I can't remember that it made any very obvious difference, but the majority of my sailing ends up in light wind situations, so the total pull on the mainsheet is usually not an issue. By the way, because the mainsheet is led to the centerboard cleat, the effective purchase is a 1.5:1 compared with 2.5:1 for the Crosby, so the ratio is 3/5 not 1/2 between these two styles. (They compare to 3:1 and 5:1 center-boom tackles).

The split main does not center the boom. The two ends of the main sheet must necessarily pull with the same force on each side of the boom, which in a symmetric case would mean that there's no net sideways force. Therefore, in order to counteract the sideways sail force, the boom has to be off center.

Incidentally, the more you use the vang, the more asymmetric the triangle formed by the split mainsheet has to be to generate the necessary side force.

With a Crosby style rig you could replace the fixed triangle by a triangular loop, which you could then adjust. Phill's description talks about a knot he puts in that loop which he can hook over a hook underneath his transom. that fixes the apex of the triangle with the block for the mainsheet in a position amidships.

You could easily add another hook position that would bring the apex of the triangle further to windward. However, Phill, and perhaps others(?), have written here that trimming the main sail to centerline or even to windward is not beneficial on the DS in their experience.

[K.C. Walker]

Okay, I may be mistaken. What I thought the "Crosby rig" was as you first described your rig, that is with the line attached to the boom (or beckett), down to the starboard block, over to the port block, up to the boom block, and forward, giving 2:1 at the end before going forward. The snipe style "split main" is a spliced main sheet that divides just inside the end boom block (when close hauled), goes out through the block and attaches securely to port and starboard rails. Therefore, this method does center the boom, only gives a 1:1 purchase at the end before going forward. My understanding was that the simple bridal and the rope triangle traveler were different and not the "Crosby rig".

KC

[GreenLake]

KC,
quite possibly I've been guilty of mixing up the terminology. Easy to do, when there are so few diagrams in these discussions.

I found this variant when looking for a definition:


It's different again from any of the configurations we've discussed here.