Your
boat needs a long, full
keel and a well balanced sail plan, plus a boomed sail forward [fore staysl, e.g.]. My 35' Colvin designed schooner sailed herself with sheet to tiller steering for days at a time without a hand to
helm. Inside
Puget Sound, I also used it frequently. A line from the fore staysl boom to windward thru a block, thence down the windward side to a block to lead the line to the tiller. Wrap the line a few turns around the tiller. Use surgical tubing on the lee side,
experiment with that to get the right strength, and you will need to be able to adjust it for stronger
wind. I used a double length with an eye on each one so I could use one or both. the whole setup is dirt
cheap, simple, quick to set up or release and is gadget free. I have heard of people doing it with the main boom, but I suspect it is much more difficult to use, due to the enormous
power of the main boom. the schooner I am building likewise has a full
keel and boomed fore staysl so I do not imagine I will need anything but the simple sheet to tiller rig. If you can find a copy of Letcher's book [try libraries] he gives very clear directions to make it work. I called my system the 'Pilot of the Aleutka', after Slocum's comment and using Letcher's boat name.