Windvane self steering for CD25

[Neil Gordon]

An autohelm will point you directly where you want to go but you might not be able to trim your sails to get good performance. On the other hand, once you have trimmed to get good performance using the wind you have, a wind vane will keep you in that mode. You will be making your best SOG. Even taking tacks and jibes into account, won't this get you where you want to go faster? It just seems that using an autohelm defeats some of the basic principles of sailing.

It's not SOG that gets you there the fastest, it's VMG. Best speed and best direction (i.e., pointing to where you're going) both need to be taken into account.

If you steer based on wind, shifts might take you further from your destination, including totally the wrong way. Further, you might be close hauled sailing straight for your waypoint when the wind shifts. Now you're sailing away from the waypoint where you might trim your sails for reaching and (i) sail faster and (ii) sail straighter.

You have similar issues, of course, if you steer based on a compass course. One advantage is that wind shifts will generally be apparent.

Note that the ST2000, for example, will steer either by compass or wind, provided it has input.

[Jim Davis]

joelcunningham wrote:
An autohelm will point you directly where you want to go but you might not be able to trim your sails to get good performance. On the other hand, once you have trimmed to get good performance using the wind you have, a wind vane will keep you in that mode. You will be making your best SOG. Even taking tacks and jibes into account, won't this get you where you want to go faster? It just seems that using an autohelm defeats some of the basic principles of sailing.

Joel

The best way to think of either a windvane or auto pilot is that it is nothing more than a helmsman who does not drink your beer. Like all helmsmen they have their strengths, weaknesses and have to be supervised. As the skipper you still have to select/set the course that you want, or can make good and then trim accordingly. Every course change and tack requires that you go through the drill again. The big plus is that your "helmsman" does the steering while you trim the sails, navigate, eat, relax and visit the head.

[riveredge]

I've concluded the st2000 is my next big purchase. I may still add wind vane steering down the road but it sounds like autohelm will be a great asset in any event. I think the advice to buy the 2000 instead of 1000 is good and I might have done otherwise without your help as well. Thanks.

[Neil Gordon]

I've concluded the st2000 is my next big purchase.

Check the prices online as there's a pretty good spread between okay and best.

Installation is fairly straightforward but be patient, follow the instructions and measure at least twice.

[Zeida]

FWIW... on my 1980 CD25 which I had for over 18 years, I had an Autohelm ST1000 tiller Pilot. It was PERFECT. Very simple to install, did not take up any real space in the cockpit, easy to operate, a joy to have. Anything more than that on a CD25 is a major overkill...UNLESS you are planning real offshore sailing, in which case you have to do major modifications to prep the boat, which is basically a wonderful coastal cruiser. you will love your Autohelm.

[riveredge]

Thanks. I appreciate knowing your experience I'll think about the overkill factor. What do you think a CD25 needs to make it tough enough for off shore sailing?

[Troy Scott]

a good inspection of the rig
Sturdy sails
a Good dodger
some means of holding the lowest board in the companionway

this list will grow

[riveredge]

Except for the dodger, which I'm not sure I agree I'd need, those sound like things you'd check on any boat before putting out to sea. I'd go for side spray clothes. I think it would be prudent to beef up the hatch covers too. Anything else? I've been wondering if I should criss cross the cockpit drain hoses to prevent siphoning but I'm not sure how to get through all the factory installed liners in the cockpit lockers. I've installed a Whale bilge pump. I put the pump inside a cabin quarter berth so pumping could be done out of the weather. Drilling through the cabin sole to run the hose I saw first hand how tough the boat was built.

[Troy Scott]

Sounds like you have an adventure in mind!

[riveredge]

And thinking. John Vigor makes a big point in his book that he's not talking about CD25's. He's only saying CD25 "D"s are capable of "taking you anywhere". But aside from pointing out that the original 25's have cramped cabins, which says nothing about their seaworthiness, he doesn't explain why they aren't capable. He also touts the diesel engine as being more suited to offshore work. Others, like the Atom Voyages guy, rip their inboards out and retrofit their boats with outboard wells for blue water trips. CD25's have somewhat shallower keels and less displacement than the "D"s but their capsize numbers and other specs look quite respectable to me. So I'd like to know what others think are the factors that make CD25s unfit for ocean going.

[barfwinkle]

and thats the need for a dodger. I recently bought one for my 25D and in June of 2009 while heading from St Michaels back door back to Solomons Is I would have killed for a dodger. In my humble opinion you will too in rough seas.

Good Luck and Fair winds

[Dick Kobayashi]

My impression is that you are venturing further into embayed waters not on to blue waters. This means you can time trips with weather windows and there will be place to tuck into if conditions turn foul. Stick to the basic upgrades and GO.

[riveredge]

That is right, Dick. My upcoming voyaging will be as you describe. I'm also planning to make short forays into heavier weather to develop and practice changing sails, reefing, heaving to etc. in stronger winds with heavier seas. When I was younger I'd take the Victoria 18 out in 30 knots of wind for fun. Reefing the main was an abstract notion I never tried back then. Now I'm older and I want to be safer, more controlled and better skilled.[/quote]

[Troy Scott]

The basic autohelm or tillerpilot will steer the CD25. BUT, the newer, smarter ST2000, with the extra bells and whistles, will do a better, more intelligent job. Most any autopilot will do an OK job if it isn't having to fight an unbalanced helm. CD25s have notorious weather helm. This is something that can be only partially addressed in the rigging. When you get new sails, you can explain this to your sailmaker (who has probably heard this many times) and he can help by making the main flatter, etc.. My CD25 went to weather best with a 150 Genoa and double-reefed, flattened main. I sometimes sailed her with the 150 Genoa alone. That's when she felt best balanced going to weather.

A small amount of weather helm is a safety factor and necessary for stability. A lot of weather helm slows you down, a lot, and puts constant strain on your tiller/rudder system. It will also make your autopilot use a lot more electricity and wear itself out sooner.

[riveredge]

My last boat was a Marshall Sanderling Catboat so I'm very familiar with the rigors of weather helm. Reefing early and often is the best way to control it on the catboat too, I found. Because I'm comparing it to the Sanderling, I guess, my CD25 has seemed quite well balanced so far. I've bought a new Sobstad mainsail that is loose footed so theoretically (if I can pull hard enough) I can flatten the sail even when its full. Another fun thing to fiddle with and I also understand better why the ST2000 may be better for my boat than the ST1000.