Adequate Tiller Pilot for 37’ 15000 lb Boat

[Ardbeg]

I have Raymarine ST70 autopilot on a chain ( as opposed to belt) for 10 years and never had a problem except under extreme conditions the chain jumped a sprocket 2x. The chain jump went thump then then pilot continued albeit with the wheel not centered. Boat is 18000+ lbs.

[Mike OReilly]

Leroy, my 37-foot boat is a tiller-driven, barn door rudder style. It rings in at 30,000#. I ran into the same issue you're facing. I couldn't find one rated high enough.

I ended up buying the Raymarine SPX-5 GP which was rated for 16,500#. I'm not sure if it's still available, but it was the best I could find. I was unaware of Pelagic (and wish I had known ).


https://www.raymarine.com/view/index-id=349.html


Anyway, I've used this Raymarine, which is woefully under rated for my boat. And I'm happy to say, it has served me well for many years now. Although I have a windvane as my primary self-steerer, this TP has been used for extended periods in rough sailing conditions, and it has yet to let me down.

My plan has always been to buy a Pelagic once this one dies, but so far, so good.

[CarinaPDX]

I have had ST4000, ST4000+, and currently SP X-5, all GP versions. The linear drive is the same for all of them, and Carina at 23k# has broken them all - repeatedly. it invariably happens when a quartering or overtaking wave hits the quarter and starts a sudden yaw, which the AP tries to steer against but the forces are too large.

I originally started talking to Brian at Pelagic (years ago) as I was hoping to find an alternative. I really like his system, although I did not think the original drive was up to solving my problem. The new heavy duty one is, by a long ways. The controller drive circuit has always been powerful enough for hefty drive motors. He added support for wind input via NMEA 0183 but I have never been able to convince him to add steering using the XTE sentence (cross-track error). I really value that ability to stick on track to a waypoint in conditions where there is substantial, and especially varying, leeway. Without that I will probably stick with the X-5 and rig an H-bridge drive to amplify the controller outputs. The Pelagic HD drive looks to be the way I will go as well.

Greg

[wingssail]

We use a Raymarine X-5 and a ST4000GP drive unit. The model numbers have changed by now. I think Raymarine EV-1 and EV100 would be equivalent.

Our boat is bigger and more powerful than the Santana 37.

The point is WE DON'T USE IT SAILING!

If we are under sail we use the windvane. You cannot expect an underpowered tiller pilot to handle your boat in waves or big wind.