few autopilot questions

[Lostsailor13]

Finally ordered autopilot,plan on doing install myself and just wondering where some of the trawler guys mounted their autopilot components,thinking of mounting pump under the helm station in salon,any pointers would be appreciated

 

[Portage_Bay]

I've seen lots of AP pumps in the lazarette. My current one is in the electical locker below the lower helm. That locker extends from the help down to the engine room deck level. That is where the pump is. Warm, dry easy to keep an eye on. Close to the DC power source for smaller cables and less voltage loss. I don't think for most systems it matters as long as you can Tee it into the lines and bleed it when done.

 

[mike66]

My Albin 40 has it located about a foot below the lower helm pump, with the course computer above and forward. Short wire runs and as stated high and dry.

 

[jleonard]

Mine is below the lower helm also. Only a short distance below the lower helm pump and the junction Ts for the hydraulic lines.
I bought mini shut-off valves from McMaster-Carr online and had them ready when I disconnected the hydraulic lines. I lost maybe 2 teaspoons full of fluid tops and when the shut-offs were installed it was easy to connect pre-made hydraulic hoses (again from McMaster) to the pump.
Hope this helps.
Have fun.

 

[AnsleyS]

My only caution about mounting the pump under the helm is the noise of the pump. We have ours in the aft lazerette by the rudder post and I can still hear it from the pilothouse.

 

[DDW]

Keep the magnetic heading sensor away from magnetic sources, especially changing ones. That includes big chunks of iron or steel, electric motors, and high current electric circuits. Also low and near the center of the boat, though that is less of a problem on a motorboat.

 

[motion30]

Finally ordered autopilot,plan on doing install myself and just wondering where some of the trawler guys mounted their autopilot components,thinking of mounting pump under the helm station in salon,any pointers would be appreciated

I initially located my pump under the flybridge helm station. It was loud and tiresome. I relocated it to be back near the cylinder by the rudder. makes for much more peaceful trips

 

[Jeff F]

I initially located my pump under the flybridge helm station. It was loud and tiresome. I relocated it to be back near the cylinder by the rudder. makes for much more peaceful trips

My last boat had the pump buried amidships and I never heard it. My current boat has it near the helm. Now that I've gotten used to it, I find the sound comforting and just one more indication that all is normal.

But I've got a lot of engine noise. It's just part of the din

 

[mvweebles]

Keep the pump low so if system loses fluid you will maintain steerage via the AP pump. My AP brain box was in aft lazarette near rudder. Good location on a W36.

Hard part is the fluxgate/compass. Low center is good, but need to stay away from electric motors. Highly specific to your boat, not just W36s. Mine has a stall shower in thr stateroom witb a sump pump beneath. Otherwise forward bilge area would be a good location. Might be on your boat.

Please update on where you decide to locate the compass.

Peter

 

[jleonard]

I mounted my compass below the floor of the galley (galley down).
It was actually on top of the fiberglass holding tank.

 

[HeadedToTexas]

The compass on my old Simrad AP16 system is low amidships mounted on top of the holding tank. My pump is mounted amidships on the forward engine room bulkhead. It's all convenient and accessible.

 

[bshanafelt]

I ended up relocating the fluxgate compass & rate sensor(corrects for mag).

Comnav equipment. Sensor previously centered fore and aft.

I moved the location of the compass low and somewhat aft of center. The response during following seas is substantially quicker as the movement of the stern is picked up faster than having the sensor at the axis of the movement.

Works well & the a/p is able to drive the boat well up to 5-6' following waves.

I try not to be out in water larger than that typically

 

[bkcorwin]

You could also just add a satellite compass and avoid the issues with magnetic interference in the fluxgate.

 

[Bmarler]

I ended up relocating the fluxgate compass & rate sensor(corrects for mag).

Comnav equipment. Sensor previously centered fore and aft.

I moved the location of the compass low and somewhat aft of center. The response during following seas is substantially quicker as the movement of the stern is picked up faster than having the sensor at the axis of the movement.

Works well & the a/p is able to drive the boat well up to 5-6' following waves.

I try not to be out in water larger than that typically

i need to relocate my comnav compass too. some one decided to mount it right next to the main wiring chase from the pilothouse. right now, every time someone flushes the fwd head it turns 15 degree to port.
how far away from any wiring and metal were you able to locate yours? i have a lot of challenges to overcome with my house bank under the floor down below.

 

[Bmarler]

You could also just add a satellite compass and avoid the issues with magnetic interference in the fluxgate.

i'm going to look into this, but last time i looked sat compasses were pretty expensive.

 

[twistedtree]

i'm going to look into this, but last time i looked sat compasses were pretty expensive.

$800-1000, and includes a high quality GPS

 

[Jeff F]

$800-1000, and includes a high quality GPS

Do they also give rate data? I'm wondering whether they're a full replacement for the multi-axis sensor that modern APs use.

 

[bkcorwin]

Something like a furuno scx20 which is a 1300$ sat compass gives you 10hz heading and position data for autopilots and lower rate rate of turn data and like 20 other sentences.

It does give really good pitch heave roll data as well..

 

[sean9c]

Could you please recommend one

$800-1000, and includes a high quality GPS

 

[twistedtree]

Do they also give rate data? I'm wondering whether they're a full replacement for the multi-axis sensor that modern APs use.

Absolutely. ROT, heading, all the GPS stuff, and typically pitch, roll, and heave. Not 100% sure if the Scx20 has the later, but probably. They are an improvement in every way over a rate compass or fluxgate. Data rates are min 10hz, and better units will do 20hz, and some even 40hz.

 

[twistedtree]

Could you please recommend one

Brian’s recommendation for the Furuno would be top of the list, but it sounds like it might be a bit higher $. Simrad and others sell the hemisphere device ( they are the supplier for I think everyone except Furuno). Simrad calls it the HS60. I expect all the usual suspects offer one too.

 

[bkcorwin]

Could you please recommend one

Some of the recommendations would depend on what you have to hook it up to. Cheaper models generally lack diversity in connections.

Furuno for example
scx20 is only a single nmea2k port
scx21 is 3 Ports NMEA0183, Tx 3 Ch, Rx 2 Ch

sc70 has every connection under the sun.

price goes from 1300 to 5000.

What do you need?

 

[Lostsailor13]

Worked out nice

You can see we’re the display is mounted,I mounted the course computer under the helm in the spot were the wiring and steering is,and the compass was mounted behind the steps going down to focsle absolutely perfect spot,made custom stainless bracket for rudder reference indicator,probably will install that today,then just have to do pump

 

[Lostsailor13]

All the easy stuff,I think the worst part will be bleeding the system,have never attempted any work on the Wagner system since I bought the boat

 

[mvweebles]

My Wagner helm pumps had a 1/4" NPT vent/fill fitting. Had a 3" nipple with a small cap with dipstick. To bleed, will need to adapt a hose barb to the nipple and connect a setup similar to a brake bleed temp reservoir. My old system had 1/2" copper tubing which holds a remarkable amount of fluid. Over a gallon.

Good luck.

Peter

 

[Lostsailor13]

Today’s progress

That’s about where the pump will mount,gonna make a riser block for the pump out of delrin or Teflon about .75 thick,and now thinking to slot the holes on bracket with split collar that mounts to rudder post for some easy adjustment on the ball joint,the blue sharpie represents roughy the slots

 

[Circumnavigator]

We put the Simrad HS80 on Fintry about five years ago -- she's an all Furuno boat, but the HS80 was much cheaper than the cheapest Furuno Satellite compass at the time. Entirely satisfactory.


We put a Furuno SCX-20 on Morning Light. They're now down close to the price of a rate compass. Also entirely satisfactory.


Aside from the fact that you can go under bridges, over tunnels, and through locks without the compass sending you astray, the GPS in a satellite compass is able to compensate for the fact than when the boat rolls, the GPS antenna moves sideways, which causes an ordinary GPS to miscalculate COG. Highly recommended.


Jim

 

[bshanafelt]

Bmarler
Don’t know which COMNAV unit you have, but if it’s a 1001 or 2001, then it is not an easy matter to go to satellite
you need some intermediate electronics to decipher the satellite compass data and these parts are pretty spendy

To the question of where exactly I ended up putting my compass and rate sensor, I have a chase that is just below floor level in the saloon and that’s where I put it.
My fuel tanks are aluminum and are located each side of the chase referred to above, so there’s no ferrous metal or other interference

 

[Prhugret]

AP location

Four years ago I replaced an old Robinson AP with a new Raymarine Axiom networked system. It has worked flawlessly after an initial installation issue. The issue was the location of the Autopilot Sensor.

I had mounted the Sensor in a clean/dry and empty locker beneath a dinette bench seat. The system came up beautifully at the dock and all indications were that I had done the job. However, when I did the sea trial, the system wouldn’t hold a course or go beyond a 180 degree turn.

I spoke with another boater who had done a similar installation. He came aboard, looked at the installation and then asked me to open the stair hatch to the engine room. “Ah ha, the metal clad hot water tank is on the same bulkhead and just behind the Sensor. This is causing the interference.” The solution was to simply move the sensor 4’ away from the “old” location. No more interference! The system works as it was advertised.

 

[Arc]

The further you can get the rudder indicator from the quadrant, the more accurate it will be.