Marine Service Companies for Gyro and Magnetic Compasses

A compass is only as accurate as its last service. Magnetic compasses drift over time as the ship's own magnetism changes, and gyro compasses need regular checks on bearings, electronics, and alignment to keep their heading data within tolerance. Skipping these jobs leads to course errors, autopilot faults, and failed surveys.

RecordsMarine has built a directory of marine service companies for gyro and magnetic compasses, helping fleets find qualified technicians wherever a vessel docks.

What Compass Servicing Covers

Compass work falls into two main streams, each with its own scope.

Magnetic compass servicing usually means fluid top-up or replacement, bubble removal, lubber line checks, and on-deck deviation adjustment. A licensed compass adjuster swings the ship through known headings to build a new deviation card, which then stays at the bridge for reference.

Gyro compass servicing is more technical. It includes alignment checks against true north, bearing inspection, slip ring cleaning, replacement of pickoff coils, software updates, and sensor recalibration.

Repeater compasses, course recorders, and heading distribution boxes also need testing during the same visit.

Working with companies that provide servicing of gyro and magnetic compasses gives fleets a single point of contact for both jobs, which simplifies planning during port calls.

Where Compass Services Apply

Every vessel that falls under SOLAS Chapter V needs scheduled compass attention. Magnetic compasses must be adjusted after major structural work, a change of trade route, electrical equipment swaps, or any time the deviation card looks doubtful. Gyro units need annual checks at a minimum, with deeper servicing every five years or after any electrical fault.

Most ports with regular merchant traffic now have at least one qualified service firm. Larger hubs such as Rotterdam, Singapore, Houston, and Hamburg offer broader coverage with same-day mobilization options.

How to Choose a Compass Service Firm

Quality varies in this field, so a careful selection saves time later. Before booking, check:

• Valid compass adjuster license recognized by your flag state
• Brand-specific authorization for gyro models on your vessel
• Field engineers with current training certificates
• Calibration tools that meet IEC and ISO standards
• Clear reporting on adjustments, parts replaced, and software versions
• Realistic mobilization windows in your usual ports

A recognized firm issues a certificate after the visit, which class surveyors and port state inspectors accept without question.

Standards and Compliance

Compass servicing must follow SOLAS Chapter V, IMO Resolution A.382 for magnetic compasses, A.424 for gyro models, and ISO 25862 for installation and testing. Deviation cards, calibration reports, and service certificates form part of the navigation record book and are checked during every routine survey.

Frequently Asked Questions

How often should a magnetic compass be adjusted?

At least every two years, plus after any major hull or electrical work that could change onboard magnetism.

How long does a gyro compass service take?

A standard annual visit lasts 3 to 6 hours. Major overhauls run longer and may need dry dock time.

Can servicing be done at anchor?

Magnetic compass swinging needs the ship to be underway. Gyro work can usually be done alongside or at anchor.

Are remote services available?

Some firms now offer remote diagnostics for gyro electronics, which can resolve software faults without a port call.

Find Compass Service Provider Near You

The directory below lists vetted compass service firms covering ports on every major trading route. Check the listings to find a match for your fleet.