Jump to content

Linked mainsheet-outhaul examples


Recommended Posts

If have seen a setup of a 29er with the main downhaul and outhaul connected together so that both eased together.  Any examples out there of a dinghy main outhaul linked to the mainsheet tension?

Link to post
Share on other sites

Yes, I remember someone registering a design where the gooseneck pivot was a 2-3 inches behind the mast, so that when the main was eased the distance from luff to leach reduced and the camber in the foot increased - equivalent to easing the out haul.  The only issue is when you ease the sheet to dump power you are actually simultaneously powering up the lower main.

Edit: Combining the outhaul with kicker probably makes the most sense.

Link to post
Share on other sites

I don't think linking the outhaul to the mainsheet tension is a good idea. While in some conditions it would work well, in others, it wouldn't.

For example, you want less outhaul upwind when there is a bit of chop, to power through, while pointing as high as you can to optimise VMG.

You generally want to flatten the top portion of the sail ahead of the bottom third, as the bottom of the sail has less torque - more power lower down is a good thing, until you become overpowered.

I can't think of any boat I'd not want independent control of the outhaul.

 

Link to post
Share on other sites

You couple the Outhaul to the Downhaul and you end up with a Camber control.

Leave the vang alone, it needs to remain independent.

We do the above on the C-Rigs (Laser) and also the WING.

On Looney Tunes (1995) we coupled the Mainsheet to the Jib leach tension, so we allow the jib track (self tracker) to lift when you eased more than X mainsheet, and you pulled it back down when you snugged it back on.   Took some fiddling, we had a "fine-tune" on the boat and when we got it working it was pretty amazing, the boat accelerated nicely especially in Garda, Malveno & Geneva where Looney Tunes did most of its sailing.   Not sure what they did with it when they got back to HK, we where into the 49er by then.    It's all about ratio's!

It certainly is on the "to do list" (jib track lift with mainsheet ease) for the next iteration of the 49er.    I expect that the Camber Control system will find its way onto 49er pretty quickly, it's already in use on 29erC's.

                      jB

 

  • Like 1
Link to post
Share on other sites
12 minutes ago, JulianB said:

You couple the Outhaul to the Downhaul and you end up with a Camber control.

Leave the vang alone, it needs to remain independent.

We do the above on the C-Rigs (Laser) and also the WING.

On Looney Tunes (1995) we coupled the Mainsheet to the Jib leach tension, so we allow the jib track (self tracker) to lift when you eased more than X mainsheet, and you pulled it back down when you snugged it back on.   Took some fiddling, we had a "fine-tune" on the boat and when we got it working it was pretty amazing, the boat accelerated nicely especially in Garda, Malveno & Geneva where Looney Tunes did most of its sailing.   Not sure what they did with it when they got back to HK, we where into the 49er by then.    It's all about ratio's!

It certainly is on the "to do list" (jib track lift with mainsheet ease) for the next iteration of the 49er.    I expect that the Camber Control system will find its way onto 49er pretty quickly, it's already in use on 29erC's.

                      jB

For me, I'd still want independent control.

Kinda manual versus auto - and I'd concede there will be a day that a single Outhaul and Downhaul control makes sense in 99% of sailing conditions. The only time that I can think of is in very light conditions with the occasional freaky wind conditions, where the wind directions at the top of the mast is different to the bottom.

Trimming for me is all about the tell tales.

Link to post
Share on other sites

I've been experimenting with tying the ends of my outhaul and Cunningham on my Laser and have been pretty satisfied.  The two advantages I see are 1) I can quickly depower the sail when needed and 2. The control on the opposite side of the boat is more accessible (given ILCA's strict rules).  So far doing so hasn't inhibited my ability to adjust each independently.  I just grab the joined line and pull the appropriate half.  If the weather holds for sailing tomorrow, I'll try to remember to take a picture.

Link to post
Share on other sites
8 hours ago, JulianB said:

You couple the Outhaul to the Downhaul and you end up with a Camber control.

Leave the vang alone, it needs to remain independent.

We do the above on the C-Rigs (Laser) and also the WING.

On Looney Tunes (1995) we coupled the Mainsheet to the Jib leach tension, so we allow the jib track (self tracker) to lift when you eased more than X mainsheet, and you pulled it back down when you snugged it back on.   Took some fiddling, we had a "fine-tune" on the boat and when we got it working it was pretty amazing, the boat accelerated nicely especially in Garda, Malveno & Geneva where Looney Tunes did most of its sailing.   Not sure what they did with it when they got back to HK, we where into the 49er by then.    It's all about ratio's!

It certainly is on the "to do list" (jib track lift with mainsheet ease) for the next iteration of the 49er.    I expect that the Camber Control system will find its way onto 49er pretty quickly, it's already in use on 29erC's.

                      jB

 

This is interesting. Could you post a diagram of the line path from the main sheet to the jib leach?

Link to post
Share on other sites

Home - Australian 18 Footers League

So this is a image that's off the web of Looney Tunes,  I'm steering, Graham Bird is in the middle and Ramindo Tonteneli is in the beak, Lake Malveno (nth of Garda) it would have been May 1994 or 5.    Note it has a wishbone rig, so the main-sheet was straight up and down off a bridle off the transom, I think the active part of the main-sheet (the bit that lead to the sheet-hand,) went to the top of the rudder and fwd.   We had "necked" the main-sheet down so it was probably 4mm tail that did the active work upwind, then fattened out to 6-7mm main-sheet just before the ratchet block in the middle of the floor, and as part of that necking, we made a bump, probably out to 10mm.      The blocks at the back where not a issue because they would have been 40mm with a rope capacity of 10mm, so the bump simply went through/around them.   The bump never made it to the ratchet block so that was not a issue.   We had a "throat" so it would have been 20mm long, very likely hand made from a bit of delrin/acetal, bored a 8mm hole down the guts, round the edges so the rope passed through it easily then a 3/16" hole on one side.

image.png.40fbeaee94ba6ad25b3e88e8e231b9ea.png

The throat, it would have been so much rougher than this, hand made, anyway,

image.thumb.png.868bbbd68b0c36a33ae3d93a8739cd5e.png

The self-tacking jib track that is presently used on the 49er is the same track use on the 18teen, then and now, exactly, probably the same curve.

But we secured the center of the jib track via 2 M5 bolt to the mast step, there was a flat-angled plate as part of the mast step, so in the middle we immobilised it and it was shorter than a 49er, we went to 9° and that was it.   The tip of the track where held back by a bit of M3 wire, 200 mm long, approx, one end had a eye swaged on, and the other end a terminal thread (M6).   You bolted the eye to the deck (at a tangential angle behind the track) very firmly, (M6 bolt) and the thread part of the other end, the threaded swage, then past straight through the jib track.    The big advantage of that was you could super accurately adjust the fore-aft position of the track, via the screw thread.    Up and down on a std boat we had another bit of wire or rod, with a eye bent at 80° and bolted down to the deck, and the other threaded bit again passed through the track, and we again had a screw thread adjustment, to tune height.   With Looney Tunes we replaced that vertical thread/eye, with a bit of flex wire (7:64, probably 3/32 or 2.5mm) that was then attached the the end of the 4:1 (the white line)  so as you eased the main-sheet the it allowed the track to move upwards.     You only want 20mm of movement max, I'm pretty sure we used a lever for the purchase, because remember this was 1994-5 and even cascade purchase system had quite a bit of friction.     And now I think of it, we where surprised by the "immediacy" off effect and upped the leverage significantly, certainly to 8:1, possibly higher.

Guys, it was 26-27 years ago, sorry, and I'm old, I am now thinking that the main-sheet went fwd, up the mast to the Wish-bone GN and then back along one of the wish-bone arms, in which case you flip the whole white part and get rid of the turning block.

The essence of what we did dose not alter, a irregularity in main-sheet thickness (bump), engaged with a stopper (throat) and that drove via a purchase system to manipulate the leach tension.

 

  • Like 1
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...