Location of fluxgate rate/gyro compass

[Pub911]

When installing the Simrad RC42 compass, the manual advises to keep the unit 6' away from the engine and away from other 'large metal objects' or sources of strong electrical fields (e.g. batteries & cable runs, inverters, chargers, etc). This leaves me with two options: far forward or far aft.

Which is better for compass-driven auto-pilot performance?

[Giulietta]

Either, or..

the best location is one that is as low as the water line, in the center line of the boat in the middle. This to stop the thing from moving too much with boat movement.

However, it is not that critical if its not dead center.

Just keep it away from the metal objects that are near, such as engine, keel, mast shrouds etc...you should be fine..like I said.. not that critical

[sailingfool]

The compass for my Alpha 3000 AP also recommended installation as close to the center of the boat as possible...ending up on the inner end of the chart table.

[Giulietta]

Originally Posted by sailingfool

The compass for my Alpha 3000 AP also recommended installation as close to the center of the boat as possible...ending up on the inner end of the chart table.

So is mine..a few feet forward of the nav desk, inside the U shaped setee, slightly to port..and so far it never failed

[Valiente]

This advice is fine for a plastic boat.... but you have fewer options on a steel boat. By the looks of the port spreader, my KVH AC103 fluxgate once sat on a teak pad up there, five metres off the deck. I suspect the original owner swapped out the original pilothouse roof for the current aluminum one, because that is where the compass sits today, and I have "swung the boat" to confirm via bearings, via GPS and via the Ritchie helm compass that it is quite accurate.

Another option I have seen is on aluminum radar arches, but I can't vouch for the performance.

[AjariBonten]

Yea, Val; but everyone knows metal don't float!!!!!!

Unless, of course, it weighs the same as a duck

[eherlihy]

Originally Posted by AjariBonten

Unless, of course, it weighs the same as a duck

...in which case it is owned by a witch, and will have to be burnt.

[Pub911]

All metals are troublesome? Even an aluminum mast? FYI, the boat is plastic.

[CaptKermie]

To provide more options for mounting positions you can also mount the compass facing forward or aft and if mounted facing aft when swinging it you correct for 180 degrees to get it pointing the right direction. Worked for me on my ST4000 MKII+ I have it under the companionway steps facing aft at the waterline and centerline and between 1/3 & 1/2 the distance LWL forward of the transom, if that makes sense. I measured forward from the transom to get between 1/3 &1/2 turned out to be ideal.

[camaraderie]

Forward or aft doesn't matter. Put it wherever it will work and be closest to your control computer.