Sheet-To-Tiller Steering

Sitting at the helm for long stretches of time isn’t my favorite thing to do while sailing longer distances. In fact, when I have a guest on board, I give away the helm as soon as possible. I’d much rather be mobile and adjust sails, take photos, and generally not be tied to the tiller. However, electronic tiller pilots aren’t very effective for steering under sail – weather helm easily overpowers them, or overtakes their ability to make corrections quickly. They are good for steering under power, though. I don’t want to spend $5-6k on a windvane self-steering unit – especially since most of my sailing is in the Chesapeake – seems like overkill if I’m not going to cross an ocean (no plans for that!). So, sheet-to-tiller seems like the best alternative. I’ve always conceived it of being too complicated, or not effective on every point of sail, but I changed my perspective recently when I read the phrase “. . . every sailboat can be made to steer itself.” Hmmm. . .

I began to watch some videos on the subject, and became convinced that it was both effective and easy, so I collected the various components from my spares that I keep on board. Basically, I needed an alternate main sheet that directly and dynamically ties the boom to the tiller, and I needed a counter-balance device – in this case I used several lengths of shock cord connected to a lanyard that will connect to the slotted toe rail.

Mainsheet: runs from the end of the boom to a block fixed (at this point) to the backstay, then to a block that’s attached to the toe rail on the weather-side of the boat. This will counterbalance the tendancy for the boat to round up to weather – as wind pressure acts against the main, it’s force is transmitted to the opposite side (windward side), applying force to weather on the tiller, and subsequently causing the boat to bear off. The shock cord is attached to the leeward rail and pulls the tiller back to center line when the wind pressure lessens. Here are a few photos to illustrate:

Line from end of the boom.

Line from end of the boom.

Turning block on the backstay.

Turning block on the backstay.

Led down to the weather side to another block.

Led down to the weather side to another block.

Terminates in a cam cleat attached to the tiller. You can see the shock cord led from the opposite rail adding balancing force to the tiller.

Terminates in a cam cleat attached to the tiller. You can see the shock cord led from the opposite rail adding balancing force to the tiller.

I made up two lengths of line with snap clips to attach to the rails.  These in turn are attached to the block on one side, and the shock cord on the other. This way, when the boat is tacked or jibed, the lanyards can be easily moved to opposite sides. An advantage to having a slotted toe rail, is that the length of, and therefore the tension of the lines can be infinitely adjusted by moving the clips to adjacent slots just an inch or two at a time until the correct balance is attained.

Lanyard attached to toe rail.

Lanyard attached to toe rail.

Here's a view of the tiller-mounted cam cleat for the sheet.

Here’s a view of the tiller-mounted cam cleat for the sheet.

Another view of the sheet-lead to the tiller.

Another view of the sheet-lead to the tiller.

Leaving the mainsheet slack but attached is a critical safety consideration. That way, if the alternate sheet attached to the tiller gives way for any reason, the boom is still captured after the slack is taken up.

Leaving the mainsheet slack but attached is a critical safety consideration. That way, if the alternate sheet attached to the tiller gives way for any reason, the boom is still captured after the slack is taken up.

So how did it work? Well, pretty good for the initial experiment. I discovered unwanted friction in the block mounted to the backstay as a result of the line being led too closely to the bimini. We moved the bimini off the block, and that helped somewhat. We need to continue experimenting with lanyard positioning and sail trim before we can report total success on all points of sail. However, we did achieve stable steering on a beam reach and close reach on our first experimental day-sail. I was pretty satisfied!

 

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5 comments
    • Thanks Bob. You’re right, I should pick it up. The stuff I’ve read and viewed have been influenced by this book, and specifically referenced – the quote I cited above came from that book, I think.

  1. Johadel said:

    Great work, Rick! Anything that gives you freedom from the tiller is a good thing.

  2. Very nice. I tried on my last boat, but catamarans have a different response and it never worked.

    On the other hand, they don’t tend to build helm in a the puffs and track well, so an autopilot with a masthead vane works well. Even so, when sailing down wind with any real waves, a compass heading is much more stable than a vane (the apparent wind dances too fast).

    I really use the auto helm a lot. I’m ashamed to admit that once properly tuned, I think it’s better than me, at least after I get tired.

    • Yes, the dynamics of wind, seas, and tiller must be very different on a cat. In this case, having a fair amount of weather helm is an advantage – not always the case, and I often wish My helm was more neutral in other situations.

      As I continue to think through the dynamics and forces at work, I’m understanding where the inefficiencies are: the backstay-mounted block (loses effectiveness if the backstay deflects under sheet tension); oblique lead angles for sheet and return lines (90 degree angles are going require less force for moving the helm); length of sheet and return lanyards effect line lead angles. I also think a smaller diameter line will create less friction in the blocks.

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