deviation

[paulonvt]

How can I have been so slow? On my last boat (steel) I fitted an Autohelm ST 50 compass, it worked very well. When I was fitting out ny new (wooden) boat I transfered said compass, the fluxgate went into a cuboard next to the fridge, fridges have a magnet strip under the sealing strip on the door. 12 months to realise what was causing the deviation!!!

 

[peterb]

Had a similar problem with an ST50 compass mounted inside a clothes locker. The boat had a variable heeling error, depending on whether the jacket closest to the compass had a plastic coat hanger or a wire one!

 

[jamesjermain]

Magnetic flip

As an aside, have you read that 'some scientists' think the Earth's magnetic field is due for one of its periodic end-over-end flips with the poles swapping places - could lead to some interesting chart compass roses.

JJ

 

[bedouin]

Re: Magnetic flip

I think that's 'due for' as in 'sometime in the next 50,000 years'. Of course they've no idea whether it will happen overnight, or take a hundred years - that could make navigation by compass very exciting.

 

[Guest]

Re: Magnetic flip

The Earth's magnetic field is the cause of magnetic variation, with deviation being caused by the "components" of the vessel itself. Having a steel vessel, using a closed NECO compass, attached to the Mizzen mast, this unit is constantly feeding heading information to the steering compass and the repeater at the nav desk. Katoema has NO deviation. This system is no longer available, but the person that worked for NECO is very much alive and I have given him the information/serial no's of the relevant components. As it has been running for about 20years, it will continue for another 20!

Should anyone have a NECO, I can supply the contact info if necessary.