Compass swinging.

Fixed price all inclusive compass adjusting service.

For a fixed price quote and to book your

compass adjusting service 


 or telephone 07813890686


Compass adjusting in the West Country.

Many yacht and motor cruiser owners are taking the opportunity to have their magnetic compass adjusted and calibrated by Southcoasting Navigators in one of the picturesque ports of the West Country whilst they cruise the area. 

This is not only an efficient and interesting way to spend a couple of hours, but also very cost effective as it does not incur any travel charges to you by our compass adjusters. 

Book a compass adjusting service with Southcoasting Navigators by emailing or telephoning 07813890686. 

What you should know about a compass adjusting service.

A compass adjusting service for all types of vessels.

Paul Cunningham has now logged compass adjustments for over 2,100 compasses.   

During the service to adjust your vessels magnetic compass we shall perform the following;

  • Check the compass position, fitment and quality of operation.
  • Then you or your skipper will take the vessel to sea in order for us to fully complete a coefficients determination.
  • We will do this by swinging compass, thereby putting the vessels' head onto known bearings and/or transit position lines.
  • We will adjust and compensate the compass for minimising the detected deviation.
  • Then we will prove the compass deviations that we have calculated and observed.
  • We will then create tables of deviations and coefficients that we will leave with you on the vessel for immediate use and follw with PDF copies for the ships files.
  • Please allow 2 hours at sea for each vessel to accomplish this service.
  • Any extra added compensation magnets and/or soft iron may be charged in addition, at cost.

Contact us for a fixed price quote for our compass adjusting service.

Working hard to give outstanding customer service at the best possible prices.

Compass Adjusting, Operating COVID Safe.

During this Covid period we continue to offer our compass adjusting service to all vessels safely.
Our surveyors are all 'triple jabbed' for your crews' protection, plus social distancing where possible and with PPE mask, gloves, eye protection and hand cleaning in place. Full risk assessments available on request for masters and crew as per MCA CoSWP.
Phone 07813890686 or email for details.

Does your compass need adjusting?

A compass requires adjusting:

1. When newly fitted.

2. Every 2 years (where a record of compass deviations has not been maintained) or if deviations are excessive or the compass has defects.

3. When it becomes unreliable.

5. After structural repairs or alterations that could effect its magnetism.

5. After electrical or magnetic equipment close to the compass is added, removed or altered.
Ref: MCA Safety of Navigation – Annex 13.

A selection of the vessels compasses we have adjusted.

Ship compass adjusting service worldwide by SouthCoasting Navigators.

Compass adjusting service for all types of vessels.

We offer a service for compass adjusting for yachts, motor vessels, fishing boats, work boats, ships etc. based in South Devon UK, and servicing all ports.

The service includes:

  • check compass position.
  • fitment, quality of operation.
  • complete coefficients determination.
  • swing compass on known bearings and transits.
  • adjust and compensate compass for minimising deviation.
  • prove compass deviations.
  • create tables of deviations and coefficients.
  • Please allow 2 hours at sea for each vessel.
  • Any extra added compensation magnets will be charged in addition, at cost.

Contact us for a fixed price quote for our compass adjusting service.


If you see a vessel displaying the two flag signal code Oscar-Quebec (O-Q) please keep clear and pass with no wash. A compass adjuster is aboard and completing his compass adjustment service. 


Southcoasting Navigators no longer offer a compass repair service, but can supply and fit new magnetic compasses, if required.

Memo to boatbuilders.

Installing the magnetic steering compass.

Reference ISO 25862:2009.

 It is very important that the following guidelines are followed, in order that the magnetic steering compass performs correctly.  Unless these guidelines are followed the compass can become unusable.

 1.    If the “Safe Distance” is given for any electrical/electronic equipment in the area where the compass is to be installed, the magnetic compass should be installed outside that distance. Alternatively, the equipment should be installed at a greater distance than the “Safe Distance” away from the compass.

2.    Electrical wiring carrying DC current should be arranged in bi-polar fashion so that the magnetic fields generated by the two currents compensate each other. This can be achieved by forming a twisted pair. This includes the compass light feed wires which are supplied as a twisted pair. They should be left as such and NOT untwisted.

3.    Entertainment speakers cause a particular problem and should be installed more than 3 metres from the compass, unless the Safe Distance is known. If the Safe Distance is known this will provide the necessary guidance.

4.    Other electrical/electronic equipment where the Safe Distance is not known should be installed more than 3 metres away from the magnetic compass.

5.    Aligning the compass with the fore and aft line: Measure the distance between the centre line of the vessel and the centre of the compass bowl. On the foredeck; repeat this measurement from the centreline to the push-pit rail and mark with tape.

Place the compass in position with the shadow pin and lubber line of the compass and the tape mark all in line (transit), this will ensure that the compass is parallel with the fore and aft line of the vessel. Mark the position of the compass carefully and drill the mounting holes. Screw down.

(Ideally, it is preferable to drill just one mounting hole and secure the compass with one screw. The other holes are drilled and screws inserted after the compass is adjusted and the alignment checked)

Note: The fluxgate compass which if fitted, feeds the autopilot and other equipment, is a magnetic compass and can suffer from deviation caused by the magnetism of nearby objects. The manufacturers installation manuals should give the necessary guidance on the siting of the fluxgate. However, you should consider the location of this compass in relation to the electrical and electronic equipment onboard.

This memo produced by our own