Autopilots

[Steve]

Hi All,
This years project for my 23/III will be the addition of an autopilot. I just have a few questions.
1. Raymarine or Simrad?
2. Which model (low or mid grade)
3. Has anyone added/used a masthead wind transducer with the tillerpilot.

Thanks
Steve

[CaptK]

HI Steve -

Researching like you are I've read both good and bad about both brands. I forget which manufacturer makes it, but for the 23 I'd decided on the ST-1000 (I think this is the correct product name). It comes with a remote control so that you can steer without being at the tiller.

[Windhawk]

I see that they have the Raymarine ST-1000 on sale at Sailnet for $411.

That seems OK to me.  Keep us updated on how it works out.

[curtis]

I've looked into autopilots as well.  The ST1000plus seems like a real good
choice.  The Simrad TP10 is the least expensive.  Its a "no frills" unit
that uses its own fluxgate compass and has no external inputs or outputs
and a very basic display.

Jef Tsai had a reliability problem with an older ST1000.  I don't remember
the details.

I remember reading (elsewhere) that you should make sure you get the
"plus" and not the ST1000 without the plus.  Its been long enough that if
you buy new you almost couldn't possibly not get the plus.  I think the
difference had to do with programming and overcorrection but not sure.

The problem that Jeff had besides reliability was the ability of his ST1000 to
steer in strong conditions.  Maybe Jeff can provide the details.  This seems
to be common on big boats and small, with the problem on big boats being
that is sails aren't well balanced the tiller can overpower the autopilot.  Jeff
thought that the ST1000 overreacted on his CP19 if I remember correctly.

One thing I've read is that the "for boats up to X pounds" ratings from the
manufacturers are very overstated and it should be assumed they apply to
sailing in fair weather only.   For sailing in strong conditions you might
want to divide by 2 or 3 which would put the CP23D on one side or the other
of  the limit for the ST1000plus.  I've considered going for the ST2000plus
for that reason.  The last thing you want is an autopilot that can't cut it
when the wind picks up.  OTOH the 2000 might be overkill.

Curtis

[tsaiapex]

Like Curtis said, I have a ST1000 (not plus) on the CP19.  Both times when it failed me were during very rough conditoin.  First time was running with 4' following waves and 25 kntos wind on Pamlico Sound.  The second time was beating into 4' waves and 20 knots wind off Cape Lookout with 100% jib.  I have to say that if I had made the right judgment on sail, the ST1000 would probably not had failed.

The ST1000 has pushrod system driven by two belts and transfer gears.  When the pushrod is extended or retraced to its extreme, the motor cotinues to grind the gears even if the rod has reached its limit.  This action wears out the components.  When running down 4' waves, the CP19 got knocked around quite severly (until I realized I should have reefed the main).  The belt jumped the gear after 3 hours of bashing, but I was able to put the belt back easily.  If I had reefed earlier and slow down the boat motion, I believe the ST1000 would do just fine.

The second time was beating into 20 knots wind  4' wave.  I had the 100% jib up and the boat was very inbalanced and got knocked around at every wave.  I should have dropped the jib and raised reefed main.  The ST1000 simply had enough of my poor seamanship and burned out two trnasistors.

Since then, the ST1000 has been repaired (by friend who is a wizard with circuit board), and I installed a manual autopilot as a backup.

CP23 being a heavier boat and round bilge will have gentler motion than CP19 which will place less strain on any kind of autopilot.  I do not know what enhancements ST1000 Plus has, but I hope they put some type of limitor so the motor would stop before the pushrod reaches its limit.

One thing I have to mention about the ST1000 is that it has good waterproofing.  In both conditions I was dosed with bucket full of water every 5 seconds, there were no sign of salt water intrusion on the electronic board when I opened it.

Hope this helps.  Hope other CP23 owners will provide more feedback on their experiences on the autopilot.

Jeff Tsai
CP19, Mary Grace
Apex, NC

[Steve]

Thanks guys. I guess my final decission is between the ST1000 and the ST2000. I believe the 2000 has a faster travel time and a better drive. It may be overkill but still something to consider. Six weeks to spashdown (i hope)
Steve