Autopilot HELP... Southern Cross 35'

[Southerncross35]

I have a Southern Cross 35' with an exposed steering quadrant at the helm. this poses an issue for installing an autopilot. i had a auto helm previously but it was only rated for 16,000 lbs displacement. As she sits now we are just below 18,000 lbs. Has anyone had a similar issue or is familiar with this boat? please ill take any suggestions.

[Sailmonkey]

Exposed Quadrant? Like a wheel that runs cables to a quadrant beneath a grate in the cockpit?

Would a rotary drive work for you driving the wheel? Either below decks or above?

[Southerncross35]

Originally Posted by Sailmonkey

Exposed Quadrant? Like a wheel that runs cables to a quadrant beneath a grate in the cockpit?

Would a rotary drive work for you driving the wheel? Either below decks or above?

Yes. There is a grate in the cockpit and the quadrant is visible. All I’ve ever had was an autohelm (hooked directly to the helm) I do not know about the available systems.

[Southerncross35]

Originally Posted by Southerncross35

Yes. There is a grate in the cockpit and the quadrant is visible. All I’ve ever had was an autohelm (hooked directly to the helm) I do not know about the available systems.

I used a rotary drive. But they don’t fully cover the displacement of the vessel. (18,000 lbs)

[Sailmonkey]

Originally Posted by Southerncross35

I used a rotary drive. But they don’t fully cover the displacement of the vessel. (18,000 lbs)

We’ve got a ray marine type 1 rotary drive (driving the wheel to a rack and pinion) that’s rated to 24000 lbs. can you fit something like this below your pedestal?

[Southerncross35]

Originally Posted by Sailmonkey

We’ve got a ray marine type 1 rotary drive (driving the wheel to a rack and pinion) that’s rated to 24000 lbs. can you fit something like this below your pedestal?

I’ll have to look and see. I have no idea how it is installed. I’ll try and look for installation videos.

[MartinR]

CPT maybe!

[roland stockham]

My take is that selecting an autopilot is more about what type of use you expect than anything else. If The intended use is offshore passage making with long periods under auto pilot you should definitely be looking at an inboard pilot with either an electric or hydraulic drive and with 18,000lbs dissplacement you want it rated to at least 24,000lbs. If it is for coastal work with only short periods of use or just for motoring then something like a wheel drive/cockpit drive is fine and does not need to be right up to the boats dissplacement. The hardest work for a pilot is down wind in heavy seas wher both power and speed (of the drive unit) are critical. A lightweight drive will happily steer the boat upwind or reaching but may need an earlier reef.
With the exposed quadrent I would be cautious about electric drive. Most are sealed but not designed to take solid water. A hydrolic drive should be fine as long as you have the stainless ends. I have one mounted to a tiller hung rudder so it is completely exposed and works fine. All inboard pilot control computers need to be in a dry location, prefferably below deck but could be in a fully sealed box.

[Mike Banks]

I used a hydraulic system with a hydraulic autopilot. TMQ was the one--I was very satisfied with every aspect of it--and it had its own flux gate compass as well as a setting for GPS. Both worked well. The GPS control was especially good because it handled pre-set way points, and could sound an alarm when they were reached, so all one had to do was adjust sails--.

The only thing one had to watch, was once one switched on the autopilot, it disconnected the helm--so the autopilot switch needed to be handy if one wished to regain manual control quickly.

[hpeer]

The displacement limits are pretty meaningless. There are a whole range of issues that effect how well a particular boat will react to an AP. Probably the biggest is the captains ability to properly trim the boat to reduce weather helm. I struggle in this department.

Just looking at your Boats profile On sailboat data it looks like you have a full keel with a “Brewer bite” and a rudder that is set well aft. This should make the boat a bit easier to steer with an AP than a full keel boat but not as easy as a short fun and balanced rudder.

My gut tells me a CPT would do fine on your boat.

Then again you might want to look at Pelagic tiller pilots. The ram they sell is off the shelf from some commercial hydraulic company. They have a wide range of inexpensive rams and you might be able to find one that suits your needs. And the rams are cheap enough to carry a spare or 2.

2¢

[hpeer]

The displacement limits are pretty meaningless. There are a whole range of issues that effect how well a particular boat will react to an AP. Probably the biggest is the captains ability to properly trim the boat to reduce weather helm. I struggle in this department.

Just looking at your Boats profile On sailboat data it looks like you have a full keel with a “Brewer bite” and a rudder that is set well aft. This should make the boat a bit easier to steer with an AP than a full keel boat but not as easy as a short fun and balanced rudder. Turns lock to lock is another factor.

My gut tells me a CPT would do fine on your boat. I’ve used on on my 40,000 lb displacement cutter.

Will the CPT steer my heavy displacement boat?
The CPT will generally steer heavy displacement boats from two to eight turns lock-to-lock. The CPT has a powerful motor and gearing, and uses the mechanical advantage of the steering wheel & steering system. When sailing you must be willing to trim and balance the vessel, as you would with a windvane, to reduce weather-helm. The most common vessels using the CPT are typically 30'-50' in length with 10-40,000 lb displacement. The CPT develops up to 86 ft-lbs of torque at the wheel which is enough to handle most wheel loads.
In winds or rough conditions the boat must be balanced to reduce weather helm. With too much weather helm the belt will eventually begin to jump in its cogs, an indication its time to reef and trim the boat. Many vessels have the CPT as well as a windvane. A self-steering back-up of some sort is recommended for long distance cruising.

CPT Autopilot Inc.

Then again you might want to look at Pelagic tiller pilots. The ram they sell is off the shelf from some commercial hydraulic company. They have a wide range of inexpensive rams and you might be able to find one that suits your needs. And the rams are cheap enough to carry a spare or 2.

https://pelagicautopilot.com/

2¢

[hpeer]

The displacement limits are pretty meaningless. There are a whole range of issues that effect how well a particular boat will react to an AP. Probably the biggest is the captains ability to properly trim the boat to reduce weather helm. I struggle in this department.

Just looking at your Boats profile On sailboat data it looks like you have a full keel with a “Brewer bite” and a rudder that is set well aft. This should make the boat a bit easier to steer with an AP than a full keel boat but not as easy as a short fun and balanced rudder.

My gut tells me a CPT would do fine on your boat.

Then again you might want to look at Pelagic tiller pilots. The ram they sell is off the shelf from some commercial hydraulic company. They have a wide range of inexpensive rams and you might be able to find one that suits your needs. And the rams are cheap enough to carry a spare or 2.

2¢

[MartinR]

Personally, I would either buy a used CPT drive motor unit or some kind of electric/hydraulic ram and a tinypilot autopilot and motor controller for these.

Makes for a cheap and nice system.

https://pypilot.org

I am very impressed by mine. Very cheap, steers nicely, uses almost no electricity.

[Bill Robinson]

I have steel Ebbtide 36, long keel, a heavy displacement (28000lb), tiller steered boat. Mostly offshore, I use the windvane, but for coastal passages, or when motoring, I use a Pelagic tiller pilot, which easily handles her.