Jib sheeting and adjustable car

[walt]

I have a very manual adjustment for the fore/aft position of my jib sheet car and because its not convenient to move (especially since I mostly single hand), I just leave it in one spot. I know Jackdraw has recently mentioned that the fore/aft adjustment has good benefits.

Currently I set the jib sheet car position mostly by just looking at the jib sail shape and just leave it in one spot. I make some small adjustments in the jib sheet by just watching the tail tells.. I understand the car moving towards the bow would pull down more and tighten the leach (less twist) and moving the track back would tighten the bottom giving more twist..

But for the car moving fore/aft, what are you looking for? Would this just be a low wind/high wind setting? For a given jib sail, how much adjustment range do you typically need? What do you look for in the sail shape - or what visual indicators do you use for the car adjustment and adding in the sheet position adjustment - which of course is two variables (and I can barely deal with just one.. lol).

 

[Jackdaw]

Great question!

The FIRST thing to do is make sure your headsail has (at a minimum) 3 telltails on each side, placed at 1/3s up the luff. Like this simple setup. This is key to be able to set the car position. If you do not have telltails at least like this, do it now!

The basic idea is to set the car so all the telltails break (or luff) at the same time. What does this mean? It means that when in upwind sailtrim and in point mode, a slight heading up (pinch) will cause all the inside telltails to lift at once. That's ideal. Under lots of conditions this will be when the car is set so the sheet bisects the sail at the luff, but not always. The difference is usually caused by wind gradient; the fact that the wind is faster the higher up you go. But you have to play with it. Other factors (like windshear) can effect the base.

In moderate breeze this is the standard way to set them. As the breeze comes up however and the sail starts to get slightly overpowered, you can move the car back a bit to allow the top of the sail to slightly 'twist off' at the top and release some pressure. This will flatten the boat and allow you to sail just as fast with less sideslip. When this twisting is done the driver should now ignore the top telltails as they will stream almost all the time. Normally the driver will steer mainly to the bottom set; its easier to watch just one. If you are soling them you have to watch them all, and adjust accordingly.

When we sail we are moving the cars constantly for optimal sailshape. They really are like a traveler for your headsail. I cannot image sailing without them. Remote adjustable jib cars are easily one of the best mods you can make to a boat that did not come with them.

 

[Ken Cross]

Jackdraw: I have questions
I'm thinking of implementing the same on our Hunter 30. I'm thinking I can fasten the forward block to a padeye on the jib track. I think the track is long enough as we never move them that far forward. We are cruisers with a roller furling jib. I have never sailed on a boat with that option.

How much mechanical advantage would you recommend? Can I cleat it with a jam cleat or should I put in something more like a cam cleat or clutch? I assume light tackle will work in this case???

Ken

 

[Jackdaw]

Jackdraw: I have questions
I'm thinking of implementing the same on our Hunter 30. I'm thinking I can fasten the forward block to a padeye on the jib track. I think the track is long enough as we never move them that far forward. We are cruisers with a roller furling jib. I have never sailed on a boat with that option.

How much mechanical advantage would you recommend? Can I cleat it with a jam cleat or should I put in something more like a cam cleat or clutch? I assume light tackle will work in this case???

Ken

Good plan.

I think 3:1 will be fine for you. 4:1 is easier to pull but the blocks are more complex.

It will always be a hand load, so a Harken 150 camcleat with a Xtreme cage is great. 1/4 inch line. Small but strong blocks.

3:1 means a single block with a becket at the end of the track, and a single on the car. Go End, Car, End, back to camcleat.

You pull it forward, the sheet angle pulls it back. If under a real big load you can east the sheet slighly to adjust, or if in race mode have a crew go stand on the sheet while pulling forward.

 

[Ken Cross]

Thanks. That's the information I was looking for.

Ken

 

[JerryA]

My boat that I bought this past summer came equipped with remotely adjustable jib cars. In addition to the line pulling it forward, mine also has a simple line leading aft to pull them back. I would have thought the jib sheet under pressure would be enough for them to slide back on their own, but sometimes they need a little help. I can't imagine a boat without these now. Especially since I single-hand most of the time.

JerryA

 

[Meriachee]

The Garhauer setup is a 4.1 and with a 155 it can be tough to adjust sometimes. The reference to a traveler is not only accurate, it's a great way to think of it.