Sheet to tiller

[PabloPicasso]

Anyone use sheet to tiller self steering? Maybe I'm being a bit dumb but in the diagrams a line runs from the main sheet between the boom and traveller via a turning block to the tiller. I just can't see how this works? The main sheet will be under tension and won't move, the boom will be likewise. How does this influence the tiller?

 

[Gargleblaster]

As You luff up a bungy cord on the other side to your main sheet pulls the tiller filling your main which re-asserts tension on the tiller.

From everything I have read I think you might be better with a wind vane steering system. But that said it worked for Joshua Slocum.

 

[co256]

http://adventuresofscallywag.wordpress.com/

 

[andlauer]

Sailing headwind you may balance sails by trimming the main and genoa sheets. Then the tiller may be fitted or to a sandow or lashed slightly headwind or with a sandow on one side and the main sheet on the other.
Still in "pre-windvane" ages on following wind you could fix the twin-stay-sails sheets (left to the right and right to the left) through blocks to the tiller. Could be interesting to consider as a back-up start.
Eric

 

[ScallywagII]

Anyone use sheet to tiller self steering? Maybe I'm being a bit dumb but in the diagrams a line runs from the main sheet between the boom and traveller via a turning block to the tiller. I just can't see how this works? The main sheet will be under tension and won't move, the boom will be likewise. How does this influence the tiller?

I used sheet to tiller very successfully on an atlantic crossing in 2009 and returning the following year. You are correct that the sheets are under tension, but the tension changes as the wind direction alters, and that change of tension is what provides the steering, usually balanced by a length of bungee. The arrangement chosen will depend on the point of sail. Here are a few to get you started.

Close hauled: Most boats will have weather helm. The sheets should be set as normal. I used a bungee going across the cockpit with several turns wrapped around the tiller. Simply adjust the bungee until the helm is balanced. If the boats luffs up, it will become more upright and slow down; the bungee will pull the tiller over and put it back on course. If the boats falls off the wind a bit, the boat will heel more, giving greater weather helm, straightening the helm and restoring the course.

Close reach: As above then ease the sheets and the boat will fall off to the correct course. Trim bungee as required.

Wind aft the beam: I love this point of sail. Run the genoa sheet to its normal position, then to a block on the lee quarter, then another block on the windward coaming and clove hitched to the tiller. This sheet will thus pull the tiller to windward. The bungee balances the pull. With quartering seas there will be a bit of yawing. As the wind comes nearer the beam, the sail fills, sheet tension increases and the tiller pulls to windward. Conversely as the apparent wind moves aft, the main blankets the genoa and the sheet goes slack, bungee pulls to leeward. So Simple, So effective, yet so inexpensive that nobody promotes it because they can't charge £2000 for a length of bungee and the use of the spare blocks you probably have on board anyway. It Works! http://www.youtube.com/watch?v=DukgqTCrGhs It also works in very light following winds which many vane gears struggle with.

Dead run: I bought new sails before my crossing as the original ones were 40 years old and would not set well. I set the new and old genoas on long poles, and ran the sheets through blocks on the coamings to the tiller. It worked very well and allowed courses of about 15 degrees each side of downwind if the sheets were trimmed. http://www.youtube.com/watch?v=AHDDT1g8j0E This could also work with unequal sizes of sails because the sheet attachment on the tiller can be simply slid up or down to alter the mechanical advantage. If you don't have long poles, there are other options, or you can zigzag downwind using the quartering setup.

Beam reach: I was not lucky enough to have hundreds of miles of beam reaching, but I think this course is best served with mainsheet to tiller setups. The AYRS have some ideas in their self-steering booklet. I have tried using using one end of the mainsheet, but there is too much friction and stretch so results were not impressive. I will try again leaving the mainsheet in place, but adding another low stretch line from the end of the boom through a low friction block on the coaming to the tiller. Tighten the sheet, set the control line, then ease the sheet a little. I have yet to try this myself but there is another satisfied user if you search youTube for "how sheet to tiller self steering works on Marutji"

This is the arrangement I will be trying, but but I won't be attaching cleats to the tiller because:
1 I don't want to drill holes which could weaken tiller
2 Using clove hitches allows the point of attachment to be varied to control load on tiller. Clove hitches are supposed to be unreliable, but they worked on my tiller over thousand of miles without coming undone.
3 More flexibility is possible with bungee load by passing it across the cockpit. An extra turn can be added for more tension. Fine adjustment by gripping the turns and twisting like a motorcycle throttle.
4 I am too tight/thrifty/cautious/poor to buy unnecessary hardware.

I have written some more and diagrams about my systems on my blog: http://adventuresofscallywag.wordpress.com/ and there are other videos on my YouTube channel, with more wind, less wind etc. I am happy to offer advice if it is not clear, and can demonstrate on Scallywag in the summer, if we get one this year. It is long out of print but Gerard Dijkstra's "Self steering for yachts" is excellent. Your library may be able to get you a copy.


Please note that I am not advocating going out and buying extra bits of kit. A few spare blocks, spare line and some bungee should be on board anyway. Some experimenting may be needed to adapt a method to your boat and gear, but I am certain most tiller steered boats will steer on some if not all points of sail. I won't be refitting my vane gear, although I have the modifications which will make it much more reliable. I would suggest any JC challenger or other long distance single hander experiment and get their boat self-steering. If you have an effective vane gear, also experiment, as you don't want to join the long list of challengers who have retired due to steering gear failure.

I am not suggesting Blondie Hasler was wasting his time developing vane gears. Jester had only one Junk sail, so it would be difficult to balance. I am sure if he had bermudan rig he would have used sheet to tiller as others did before him. With one junk sail, you will probably need vane gear, although you may be able to sail upwind with a bungee. Give it a go.

Len

 

[Corribee Boy]

Thanks for posting that - I've had mixed reults with sheet to tiller so far, but am keen to try it again and your info. will be useful.

 

[ScallywagII]

More self steering methods

It is long out of print but Gerard Dijkstra's "Self steering for yachts" is excellent. Your library may be able to get you a copy.


I found a copy on Awesome books. Well worth the £2.50. As well as the methods I used, there are lots of other options, so most likely for any boat there are some ideas that will work. I have scanned the section on sheet to tiller and can email a PDF. PM if you are interested.

Len

 

[jamie N]

I've just revisited this thread after having used my DIY wind vane and sheet to tiller together, and thought that I'd give my tuppence h'apenny on it.
I've now removed my vane, but kept the trim tab as I'll fit the topside kit from WindRover once I've made it.
My trad type vane wasn't as effective as I'd wanted, and upwind wasn't as reliable as sheet to tiller, rather boom to tiller in fact.
On a beat, the sheet to tiller came in immediately it was connected: line from boom to small block on weather coaming, then onto the tiller. Once tacked, the boat getting up to speed, cleating the line from the boom in a quite slight 'weather helm' position, it was instantly happy.
Of course having a Folkboat is helpful by being long keel. I did attach bungee to it, but don't think that it was ever needed.
This worked in a variety of winds and with every reefing combination available to me.
I nearly got this method to work on a broad reach, but it wasn't reliable, and I didn't use any of the methods from post #5 for this as I'd forgotten this article, in particular those concerning the genoa.

 

[garymalmgren]

It takes time to set up and get it right,but sheet to tiller works over a long distance,