Wheel Steering Best Methods & Reduction Ratio

[sv Lorelei]

Got the plans for John Atkin's Island Princess and as per typical Atkin practices he supplies a lot of detail but leaves much to the builder as well.

The rudder shaft is vertical on IP and well braced. Plans just call for Edson steering. I was thinking of a bevel/pinion gear arrangement as I can do that with off the shelf bronze gearing and make up the shafting myself.

Or would I be better off with cable steering and putting it all together off the shelf? I've never done a wheel, or even conned a boat with one so I'm totally in foreign waters here.

What is the typical reduction used in a 37 foot boat? What pros and cons between gear/cable methods? Loss of feedback, durability, slop?

Educate me!

[nedL]

If you come up with the gearing on your own, slightly less than 6 turns of the wheel lock to lock is pretty standard (this would relate to the ratio). Gear steering (with quadrant & pinion gear) would be the most robust & dependable. Cable steering can be fine, but has more components & adjustments involved.

[Ian McColgin]

Six turns!?! Even Marmalade's very heavy helm has a bit under 4 on a powerful rack and pinion.

A good Edson worm is bomb proof. Cable introduces interesting stresses, especially if you go with and Edson style disc atop the rudder post, for which there is scant room in this design and that calls for sprocket and chain, or cable on a tiller which can be done with cable wrapped on a drum (I made such for Granuaile) and calls for careful geometry to prevent too much cable slack.

The rack and pinion is an alternative to worm, and a lively one at that. More feel to the helm. However. the quadrent must be very well engineered and supported or else the quadrent will deflect under load and you'll hop a tooth or two.

Again, bite the bullett and go worm for this boat.

[nedL]

Hmm, I'm remembering about 2 1/2 to 2 3/4 turns from midship to hard over. I will say that is with traditional 'pipe' steering on power boats (pipe steering being all bell cranks, clevises, & pipe from the steering box to the rudder post). Probably is less for sail (sorry about that). Thanks Ian :)

[Todd D]

The Edson worm gear steering on my Allied Princess 36 ketch is about 3-3/4 turns lock to lock. That is a lot less responsive than a typical cable and quadrant steered boat. Depending on the design, cable and quardant boats can be from 1 to 2 turns lock to lock. I second the idea of using a worm gear steering set from Edson (they still make them). They are totally bomb proof. The down side is that worm gear steering has almost no helm feedback. On the plus side, the wheel stays where you put it. So once you have the boat balanced up, you can just leave the wheel. I have sailed for more than 2 hours without touching the wheel and I do NOT have an autopilot.

Speaking of autopilots, if you want to fit an autopilot with worm gear steering, you have to install a drive sprocket and go with chain drive from a rotary actuator. Nothing else will work.

[Hwyl]

I'd say less than two turns, Edson is heavy duty but lacks feel, at least in the ones I've steered, but if you can get a decent ratio go for it. You should add wheel diameter into the equation, I'm talking about a big wheel.

BTW Sparkman and Stephens would not sign off on a boat if it had more than one foot pound of steering resistance. Rod would carry a one pound weight and hang it on a horizontal spoke one foot from the center of the hub, if the wheel did not move it was not an S&S

[paladin]

Gareth...the last time I was on Running Tide the wheel required a helluva lot more than one pound to move it......

[ssor]

My boat came with a 4 foot tiller but I wanted a wheel just to free up some space in the cockpit. The rudder swings about 45 degrees port and starboard. My 16 inch wheel swings 3/4 turn for hard over. That is more circumferential travel than the tiller had room for. I used a capstan drum and 4 turns of braided line on a 12 inch Edson quadrant. At hard over the wheel gets heavy but you need a light touch for the first 2 spokes.

[sv Lorelei]

Thanks guys! I suppose the Edson Wormgear is most likely the way I'll end up going. With 30 inches between the seats I don't suppose much more than a 28 inch wheel is practical. The gear mounts in a small raised deck hatch on the aft deck and I want to be able to put the wheel far enough into the cockpit so Kris can steer from behind the wheel. I'll have to play with some mock ups to see what kind of room that gives us.