Raymarine Rotary Rudder Reference Transducer

[Bolo]

Question: Does anyone have a rudder position sensor on their boat and do you feel it’s worth it or is it just another piece of equipment to buy, maintain, worry about and fix when broken? I’m in the process of upgrade the instruments on my E32-3, as part of my mast upgrades, to Raymarine electronics and I thought that while I’m at it maybe I should also install the rudder sensor.

Now I’ve lived without one for 16 years on my current boat, proceeded by a number of years on my previous boat, so I could cert live without it, but since I’m installing all this new equipment (Axiom 7 chart plotter, apparent wind, depth) that will join the existing Raymarine auto helm maybe I should just go a little further and included the rudder sensor that will read on the….chart plotter? Where exactly? Any thoughts?

 

[Pete the Cat]

I have a sensor on my Tartan and none on my Ericson autopilot. The Ericson has a newer, supposedly better, computer but the Tartan steers a more stable course with its 15 year old computer and sensor. This is only an "N" of one and the Tartan holds a course better as a vessel than my Ericson which is a bit wobbly because of less directional stability from the design--so you might not take this too seriously. The Tartan sensor is to a below deck linear autopilot and the Ericson is to a wheel pilot FWIW so it might be a bit quicker in response for that reason. Not sure this is helpful but I have a fair amount of time sailing with and without a sensor.

 

[peaman]

The Tartan sensor is to a below deck linear autopilot and the Ericson is to a wheel pilot

With a linear actuator, the piston position corresponds exactly to a rudder position, whereas a wheel pilot never knows what the rudder position is. If the linear controller doesn't "know" rudder position, at least in percent of hard over, it would be trivial to design it to. The most popular wheel pilots are inherently ignorant of rudder position.

 

[Christian Williams]

Never needed a rudder position sensor on my Ray wheel pilots. Attention to sail trim makes them work within their design limitations.

 

[brianb00]

The rudder sensors connect directly to the quadrant on a wheel pilot, or to the hydraulic ram that connects to the quadrant for a below deck solution. Wheel pilots are then aware of the rudder's position because of the direct quadrant connection. One attribute that is important is that they assure the rudder never turns so far as to damage something in the steering system due to slamming into a hard mechanical stop. Failure examples: DC motors burning out due to high currents when the rudder goes hard over, hydraulic cylinders push rods bending and distorting shaft seals causing the fluid to leak out, rudders scraping the hull and possibly jamming - very rudder design dependent, undue stress on the cables and gear in a wheel system, to name a few. Of course this won't happen if you never have a situation where the rudder hits the stop (ex: you never round up, or tangle in an object in the water). As to quality, it is best to place the rudder sensor in a dry location, or put it in a box of some kind. Also the cables are often made up with very fine wire. The connections and the internals of the sensors are subject to corrosion. Lastly, on many autopilots the R.S. is an input that adds to the feedback calculations and in certain conditions will lead to better accuracy in rougher conditions. This often goes unnoticed on many boats with lower dynamics due to large keels, skeg rudders, or boats not sailed at their performance edge. This is all very boat dependent. The sensors do fail over time and mostly due to moisture intrusion.

 

[Pete the Cat]

Never needed a rudder position sensor on my Ray wheel pilots. Attention to sail trim makes them work within their design limitations.

I would be interested if anyone with a 38 has used an under deck Raymarine unit. It might be the difference in boat design or my lack of experience, but my Raymarine linear drive unit with reference sensor (which replaced one of the old belt wheel pilots that could not manage the Tartan 37 in larger seas) did a great job of driving the boat for three days/nights in 25 to 35 kts of quartering 15' seas sailing down Baja and never faltered. No one touched the wheel for three days because it steered better than we could. I really do not think it had much to do with sail set because we were flying down the face of those waves in the night and were sometimes partially blanketed by the wave heights. I cannot imagine my Raymarine wheel pilot handling that on my Ericson 32-200. I am no engineer, but my guess is that having a rudder sensor might supply information to the computer that would be more immediate than waiting for the whole boat to change direction. The Ericson is fairly easy to set up to self sail, but is much more easily knocked askew than my larger, heavier Tartan 37. I am thinking the 38 would respond more like the Tartan, but have no experience with one.

 

[Christian Williams]

I cannot imagine my Raymarine wheel pilot handling that

Absolutely right. The Ray wheel pilot cannot handle any seas above a foot or two, or any condition where strong or abrupt helm movements are required, or any time there is strong weather helm. They're for motoring and light air, up to 15 knots in calm seas. No hydraulics, and there's zero chance of any runaway rudder damage since you can stop the little motor with your hand. I love the things, but I don't think they need a rudder sensor.

I may be a bit sensitive because this little $1500 self-steering gear gets a lot of flack, and the flack doesn't conform to my experience.

 

[Bolo]

I have a wheel pilot on the boat. Don’t think I really need the sensor but it was good to read the opinions. You’ve talked me out of it and that can be a good thing.